Weitere AWS SDK-Beispiele sind im GitHub Repo [AWS Doc SDK Examples](https://github.com/awsdocs/aws-doc-sdk-examples) verfügbar.

Die vorliegende Übersetzung wurde maschinell erstellt. Im Falle eines Konflikts oder eines Widerspruchs zwischen dieser übersetzten Fassung und der englischen Fassung (einschließlich infolge von Verzögerungen bei der Übersetzung) ist die englische Fassung maßgeblich.

# Beispiele für Amazon Cognito Identity Provider unter Verwendung von SDK für Go V2
<a name="go_2_cognito-identity-provider_code_examples"></a>

Die folgenden Codebeispiele zeigen Ihnen, wie Sie Aktionen ausführen und allgemeine Szenarien implementieren, indem Sie AWS SDK für Go V2 mit Amazon Cognito Identity Provider verwenden.

*Aktionen* sind Codeauszüge aus größeren Programmen und müssen im Kontext ausgeführt werden. Während Aktionen Ihnen zeigen, wie Sie einzelne Service-Funktionen aufrufen, können Sie Aktionen im Kontext der zugehörigen Szenarien anzeigen.

*Szenarien* sind Codebeispiele, die Ihnen zeigen, wie Sie bestimmte Aufgaben ausführen, indem Sie mehrere Funktionen innerhalb eines Service aufrufen oder mit anderen AWS-Services kombinieren.

Jedes Beispiel enthält einen Link zum vollständigen Quellcode, wo Sie Anweisungen zum Einrichten und Ausführen des Codes im Kodex finden.

**Topics**
+ [Erste Schritte](#get_started)
+ [Aktionen](#actions)
+ [Szenarien](#scenarios)

## Erste Schritte
<a name="get_started"></a>

### Hello Amazon Cognito
<a name="cognito-identity-provider_Hello_go_2_topic"></a>

Die folgenden Codebeispiele veranschaulichen die ersten Schritte mit Amazon Cognito.

**SDK für Go V2**  
 Es gibt noch mehr dazu. GitHub Hier finden Sie das vollständige Beispiel und erfahren, wie Sie das [AWS -Code-Beispiel-](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/gov2/cognito#code-examples) einrichten und ausführen. 

```
package main

import (
	"context"
	"fmt"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/config"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider/types"
)

// main uses the AWS SDK for Go V2 to create an Amazon Simple Notification Service
// (Amazon SNS) client and list the topics in your account.
// This example uses the default settings specified in your shared credentials
// and config files.
func main() {
	ctx := context.Background()
	sdkConfig, err := config.LoadDefaultConfig(ctx)
	if err != nil {
		fmt.Println("Couldn't load default configuration. Have you set up your AWS account?")
		fmt.Println(err)
		return
	}
	cognitoClient := cognitoidentityprovider.NewFromConfig(sdkConfig)
	fmt.Println("Let's list the user pools for your account.")
	var pools []types.UserPoolDescriptionType
	paginator := cognitoidentityprovider.NewListUserPoolsPaginator(
		cognitoClient, &cognitoidentityprovider.ListUserPoolsInput{MaxResults: aws.Int32(10)})
	for paginator.HasMorePages() {
		output, err := paginator.NextPage(ctx)
		if err != nil {
			log.Printf("Couldn't get user pools. Here's why: %v\n", err)
		} else {
			pools = append(pools, output.UserPools...)
		}
	}
	if len(pools) == 0 {
		fmt.Println("You don't have any user pools!")
	} else {
		for _, pool := range pools {
			fmt.Printf("\t%v: %v\n", *pool.Name, *pool.Id)
		}
	}
}
```
+  Einzelheiten zur API finden Sie [ListUserPools](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.ListUserPools)in der *AWS SDK für Go API-Referenz*. 

## Aktionen
<a name="actions"></a>

### `AdminCreateUser`
<a name="cognito-identity-provider_AdminCreateUser_go_2_topic"></a>

Das folgende Codebeispiel zeigt die Verwendung`AdminCreateUser`.

**SDK für Go V2**  
 Es gibt noch mehr dazu GitHub. Hier finden Sie das vollständige Beispiel und erfahren, wie Sie das [AWS -Code-Beispiel-](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/gov2/cognito#code-examples) einrichten und ausführen. 

```
import (
	"context"
	"errors"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider/types"
)

type CognitoActions struct {
	CognitoClient *cognitoidentityprovider.Client
}



// AdminCreateUser uses administrator credentials to add a user to a user pool. This method leaves the user
// in a state that requires they enter a new password next time they sign in.
func (actor CognitoActions) AdminCreateUser(ctx context.Context, userPoolId string, userName string, userEmail string) error {
	_, err := actor.CognitoClient.AdminCreateUser(ctx, &cognitoidentityprovider.AdminCreateUserInput{
		UserPoolId:     aws.String(userPoolId),
		Username:       aws.String(userName),
		MessageAction:  types.MessageActionTypeSuppress,
		UserAttributes: []types.AttributeType{{Name: aws.String("email"), Value: aws.String(userEmail)}},
	})
	if err != nil {
		var userExists *types.UsernameExistsException
		if errors.As(err, &userExists) {
			log.Printf("User %v already exists in the user pool.", userName)
			err = nil
		} else {
			log.Printf("Couldn't create user %v. Here's why: %v\n", userName, err)
		}
	}
	return err
}
```
+  Einzelheiten zur API finden Sie [AdminCreateUser](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.AdminCreateUser)in der *AWS SDK für Go API-Referenz*. 

### `AdminSetUserPassword`
<a name="cognito-identity-provider_AdminSetUserPassword_go_2_topic"></a>

Das folgende Codebeispiel zeigt die Verwendung`AdminSetUserPassword`.

**SDK für Go V2**  
 Es gibt noch mehr dazu GitHub. Hier finden Sie das vollständige Beispiel und erfahren, wie Sie das [AWS -Code-Beispiel-](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/gov2/cognito#code-examples) einrichten und ausführen. 

```
import (
	"context"
	"errors"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider/types"
)

type CognitoActions struct {
	CognitoClient *cognitoidentityprovider.Client
}



// AdminSetUserPassword uses administrator credentials to set a password for a user without requiring a
// temporary password.
func (actor CognitoActions) AdminSetUserPassword(ctx context.Context, userPoolId string, userName string, password string) error {
	_, err := actor.CognitoClient.AdminSetUserPassword(ctx, &cognitoidentityprovider.AdminSetUserPasswordInput{
		Password:   aws.String(password),
		UserPoolId: aws.String(userPoolId),
		Username:   aws.String(userName),
		Permanent:  true,
	})
	if err != nil {
		var invalidPassword *types.InvalidPasswordException
		if errors.As(err, &invalidPassword) {
			log.Println(*invalidPassword.Message)
		} else {
			log.Printf("Couldn't set password for user %v. Here's why: %v\n", userName, err)
		}
	}
	return err
}
```
+  Einzelheiten zur API finden Sie [AdminSetUserPassword](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.AdminSetUserPassword)in der *AWS SDK für Go API-Referenz*. 

### `ConfirmForgotPassword`
<a name="cognito-identity-provider_ConfirmForgotPassword_go_2_topic"></a>

Das folgende Codebeispiel zeigt die Verwendung`ConfirmForgotPassword`.

**SDK für Go V2**  
 Es gibt noch mehr dazu GitHub. Hier finden Sie das vollständige Beispiel und erfahren, wie Sie das [AWS -Code-Beispiel-](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/gov2/cognito#code-examples) einrichten und ausführen. 

```
import (
	"context"
	"errors"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider/types"
)

type CognitoActions struct {
	CognitoClient *cognitoidentityprovider.Client
}



// ConfirmForgotPassword confirms a user with a confirmation code and a new password.
func (actor CognitoActions) ConfirmForgotPassword(ctx context.Context, clientId string, code string, userName string, password string) error {
	_, err := actor.CognitoClient.ConfirmForgotPassword(ctx, &cognitoidentityprovider.ConfirmForgotPasswordInput{
		ClientId:         aws.String(clientId),
		ConfirmationCode: aws.String(code),
		Password:         aws.String(password),
		Username:         aws.String(userName),
	})
	if err != nil {
		var invalidPassword *types.InvalidPasswordException
		if errors.As(err, &invalidPassword) {
			log.Println(*invalidPassword.Message)
		} else {
			log.Printf("Couldn't confirm user %v. Here's why: %v", userName, err)
		}
	}
	return err
}
```
+  Einzelheiten zur API finden Sie [ConfirmForgotPassword](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.ConfirmForgotPassword)in der *AWS SDK für Go API-Referenz*. 

### `DeleteUser`
<a name="cognito-identity-provider_DeleteUser_go_2_topic"></a>

Das folgende Codebeispiel zeigt die Verwendung`DeleteUser`.

**SDK für Go V2**  
 Es gibt noch mehr dazu GitHub. Hier finden Sie das vollständige Beispiel und erfahren, wie Sie das [AWS -Code-Beispiel-](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/gov2/cognito#code-examples) einrichten und ausführen. 

```
import (
	"context"
	"errors"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider/types"
)

type CognitoActions struct {
	CognitoClient *cognitoidentityprovider.Client
}



// DeleteUser removes a user from the user pool.
func (actor CognitoActions) DeleteUser(ctx context.Context, userAccessToken string) error {
	_, err := actor.CognitoClient.DeleteUser(ctx, &cognitoidentityprovider.DeleteUserInput{
		AccessToken: aws.String(userAccessToken),
	})
	if err != nil {
		log.Printf("Couldn't delete user. Here's why: %v\n", err)
	}
	return err
}
```
+  Einzelheiten zur API finden Sie [DeleteUser](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.DeleteUser)in der *AWS SDK für Go API-Referenz*. 

### `ForgotPassword`
<a name="cognito-identity-provider_ForgotPassword_go_2_topic"></a>

Das folgende Codebeispiel zeigt die Verwendung`ForgotPassword`.

**SDK für Go V2**  
 Es gibt noch mehr dazu GitHub. Hier finden Sie das vollständige Beispiel und erfahren, wie Sie das [AWS -Code-Beispiel-](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/gov2/cognito#code-examples) einrichten und ausführen. 

```
import (
	"context"
	"errors"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider/types"
)

type CognitoActions struct {
	CognitoClient *cognitoidentityprovider.Client
}



// ForgotPassword starts a password recovery flow for a user. This flow typically sends a confirmation code
// to the user's configured notification destination, such as email.
func (actor CognitoActions) ForgotPassword(ctx context.Context, clientId string, userName string) (*types.CodeDeliveryDetailsType, error) {
	output, err := actor.CognitoClient.ForgotPassword(ctx, &cognitoidentityprovider.ForgotPasswordInput{
		ClientId: aws.String(clientId),
		Username: aws.String(userName),
	})
	if err != nil {
		log.Printf("Couldn't start password reset for user '%v'. Here;s why: %v\n", userName, err)
	}
	return output.CodeDeliveryDetails, err
}
```
+  Einzelheiten zur API finden Sie [ForgotPassword](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.ForgotPassword)in der *AWS SDK für Go API-Referenz*. 

### `InitiateAuth`
<a name="cognito-identity-provider_InitiateAuth_go_2_topic"></a>

Das folgende Codebeispiel zeigt die Verwendung`InitiateAuth`.

**SDK für Go V2**  
 Es gibt noch mehr dazu GitHub. Hier finden Sie das vollständige Beispiel und erfahren, wie Sie das [AWS -Code-Beispiel-](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/gov2/cognito#code-examples) einrichten und ausführen. 

```
import (
	"context"
	"errors"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider/types"
)

type CognitoActions struct {
	CognitoClient *cognitoidentityprovider.Client
}



// SignIn signs in a user to Amazon Cognito using a username and password authentication flow.
func (actor CognitoActions) SignIn(ctx context.Context, clientId string, userName string, password string) (*types.AuthenticationResultType, error) {
	var authResult *types.AuthenticationResultType
	output, err := actor.CognitoClient.InitiateAuth(ctx, &cognitoidentityprovider.InitiateAuthInput{
		AuthFlow:       "USER_PASSWORD_AUTH",
		ClientId:       aws.String(clientId),
		AuthParameters: map[string]string{"USERNAME": userName, "PASSWORD": password},
	})
	if err != nil {
		var resetRequired *types.PasswordResetRequiredException
		if errors.As(err, &resetRequired) {
			log.Println(*resetRequired.Message)
		} else {
			log.Printf("Couldn't sign in user %v. Here's why: %v\n", userName, err)
		}
	} else {
		authResult = output.AuthenticationResult
	}
	return authResult, err
}
```
+  Einzelheiten zur API finden Sie [InitiateAuth](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.InitiateAuth)in der *AWS SDK für Go API-Referenz*. 

### `ListUserPools`
<a name="cognito-identity-provider_ListUserPools_go_2_topic"></a>

Das folgende Codebeispiel zeigt die Verwendung`ListUserPools`.

**SDK für Go V2**  
 Es gibt noch mehr dazu GitHub. Hier finden Sie das vollständige Beispiel und erfahren, wie Sie das [AWS -Code-Beispiel-](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/gov2/cognito#code-examples) einrichten und ausführen. 

```
package main

import (
	"context"
	"fmt"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/config"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider/types"
)

// main uses the AWS SDK for Go V2 to create an Amazon Simple Notification Service
// (Amazon SNS) client and list the topics in your account.
// This example uses the default settings specified in your shared credentials
// and config files.
func main() {
	ctx := context.Background()
	sdkConfig, err := config.LoadDefaultConfig(ctx)
	if err != nil {
		fmt.Println("Couldn't load default configuration. Have you set up your AWS account?")
		fmt.Println(err)
		return
	}
	cognitoClient := cognitoidentityprovider.NewFromConfig(sdkConfig)
	fmt.Println("Let's list the user pools for your account.")
	var pools []types.UserPoolDescriptionType
	paginator := cognitoidentityprovider.NewListUserPoolsPaginator(
		cognitoClient, &cognitoidentityprovider.ListUserPoolsInput{MaxResults: aws.Int32(10)})
	for paginator.HasMorePages() {
		output, err := paginator.NextPage(ctx)
		if err != nil {
			log.Printf("Couldn't get user pools. Here's why: %v\n", err)
		} else {
			pools = append(pools, output.UserPools...)
		}
	}
	if len(pools) == 0 {
		fmt.Println("You don't have any user pools!")
	} else {
		for _, pool := range pools {
			fmt.Printf("\t%v: %v\n", *pool.Name, *pool.Id)
		}
	}
}
```
+  Einzelheiten zur API finden Sie [ListUserPools](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.ListUserPools)in der *AWS SDK für Go API-Referenz*. 

### `SignUp`
<a name="cognito-identity-provider_SignUp_go_2_topic"></a>

Das folgende Codebeispiel zeigt die Verwendung`SignUp`.

**SDK für Go V2**  
 Es gibt noch mehr dazu GitHub. Hier finden Sie das vollständige Beispiel und erfahren, wie Sie das [AWS -Code-Beispiel-](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/gov2/cognito#code-examples) einrichten und ausführen. 

```
import (
	"context"
	"errors"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider/types"
)

type CognitoActions struct {
	CognitoClient *cognitoidentityprovider.Client
}



// SignUp signs up a user with Amazon Cognito.
func (actor CognitoActions) SignUp(ctx context.Context, clientId string, userName string, password string, userEmail string) (bool, error) {
	confirmed := false
	output, err := actor.CognitoClient.SignUp(ctx, &cognitoidentityprovider.SignUpInput{
		ClientId: aws.String(clientId),
		Password: aws.String(password),
		Username: aws.String(userName),
		UserAttributes: []types.AttributeType{
			{Name: aws.String("email"), Value: aws.String(userEmail)},
		},
	})
	if err != nil {
		var invalidPassword *types.InvalidPasswordException
		if errors.As(err, &invalidPassword) {
			log.Println(*invalidPassword.Message)
		} else {
			log.Printf("Couldn't sign up user %v. Here's why: %v\n", userName, err)
		}
	} else {
		confirmed = output.UserConfirmed
	}
	return confirmed, err
}
```
+  Einzelheiten zur API finden Sie [SignUp](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.SignUp)in der *AWS SDK für Go API-Referenz*. 

### `UpdateUserPool`
<a name="cognito-identity-provider_UpdateUserPool_go_2_topic"></a>

Das folgende Codebeispiel zeigt die Verwendung`UpdateUserPool`.

**SDK für Go V2**  
 Es gibt noch mehr dazu GitHub. Hier finden Sie das vollständige Beispiel und erfahren, wie Sie das [AWS -Code-Beispiel-](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/gov2/cognito#code-examples) einrichten und ausführen. 

```
import (
	"context"
	"errors"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider/types"
)

type CognitoActions struct {
	CognitoClient *cognitoidentityprovider.Client
}



// Trigger and TriggerInfo define typed data for updating an Amazon Cognito trigger.
type Trigger int

const (
	PreSignUp Trigger = iota
	UserMigration
	PostAuthentication
)

type TriggerInfo struct {
	Trigger    Trigger
	HandlerArn *string
}

// UpdateTriggers adds or removes Lambda triggers for a user pool. When a trigger is specified with a `nil` value,
// it is removed from the user pool.
func (actor CognitoActions) UpdateTriggers(ctx context.Context, userPoolId string, triggers ...TriggerInfo) error {
	output, err := actor.CognitoClient.DescribeUserPool(ctx, &cognitoidentityprovider.DescribeUserPoolInput{
		UserPoolId: aws.String(userPoolId),
	})
	if err != nil {
		log.Printf("Couldn't get info about user pool %v. Here's why: %v\n", userPoolId, err)
		return err
	}
	lambdaConfig := output.UserPool.LambdaConfig
	for _, trigger := range triggers {
		switch trigger.Trigger {
		case PreSignUp:
			lambdaConfig.PreSignUp = trigger.HandlerArn
		case UserMigration:
			lambdaConfig.UserMigration = trigger.HandlerArn
		case PostAuthentication:
			lambdaConfig.PostAuthentication = trigger.HandlerArn
		}
	}
	_, err = actor.CognitoClient.UpdateUserPool(ctx, &cognitoidentityprovider.UpdateUserPoolInput{
		UserPoolId:   aws.String(userPoolId),
		LambdaConfig: lambdaConfig,
	})
	if err != nil {
		log.Printf("Couldn't update user pool %v. Here's why: %v\n", userPoolId, err)
	}
	return err
}
```
+  Einzelheiten zur API finden Sie [UpdateUserPool](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.UpdateUserPool)in der *AWS SDK für Go API-Referenz*. 

## Szenarien
<a name="scenarios"></a>

### Bestätigen Sie automatisch bekannte Benutzer mit einer Lambda-Funktion
<a name="cross_CognitoAutoConfirmUser_go_2_topic"></a>

Die folgenden Codebeispiele zeigen, wie bekannte Amazon-Cognito-Benutzer mit einer Lambda-Funktion automatisch bestätigt werden können.
+ Konfigurieren Sie einen Benutzerpool, um eine Lambda-Funktion für den `PreSignUp`-Trigger aufzurufen.
+ Registrieren eines Benutzers bei Amazon Cognito.
+ Die Lambda-Funktion scannt eine DynamoDB-Tabelle und bestätigt automatisch bekannte Benutzer.
+ Melden Sie sich als neuer Benutzer an und bereinigen Sie dann die Ressourcen.

**SDK für Go V2**  
 Es gibt noch mehr dazu GitHub. Hier finden Sie das vollständige Beispiel und erfahren, wie Sie das [AWS -Code-Beispiel-](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/gov2/workflows/user_pools_and_lambda_triggers#code-examples) einrichten und ausführen. 
Führen Sie ein interaktives Szenario an einem Prompt aus.  

```
import (
	"context"
	"errors"
	"log"
	"strings"
	"user_pools_and_lambda_triggers/actions"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider/types"
	"github.com/awsdocs/aws-doc-sdk-examples/gov2/demotools"
)

// AutoConfirm separates the steps of this scenario into individual functions so that
// they are simpler to read and understand.
type AutoConfirm struct {
	helper       IScenarioHelper
	questioner   demotools.IQuestioner
	resources    Resources
	cognitoActor *actions.CognitoActions
}

// NewAutoConfirm constructs a new auto confirm runner.
func NewAutoConfirm(sdkConfig aws.Config, questioner demotools.IQuestioner, helper IScenarioHelper) AutoConfirm {
	scenario := AutoConfirm{
		helper:       helper,
		questioner:   questioner,
		resources:    Resources{},
		cognitoActor: &actions.CognitoActions{CognitoClient: cognitoidentityprovider.NewFromConfig(sdkConfig)},
	}
	scenario.resources.init(scenario.cognitoActor, questioner)
	return scenario
}

// AddPreSignUpTrigger adds a Lambda handler as an invocation target for the PreSignUp trigger.
func (runner *AutoConfirm) AddPreSignUpTrigger(ctx context.Context, userPoolId string, functionArn string) {
	log.Printf("Let's add a Lambda function to handle the PreSignUp trigger from Cognito.\n" +
		"This trigger happens when a user signs up, and lets your function take action before the main Cognito\n" +
		"sign up processing occurs.\n")
	err := runner.cognitoActor.UpdateTriggers(
		ctx, userPoolId,
		actions.TriggerInfo{Trigger: actions.PreSignUp, HandlerArn: aws.String(functionArn)})
	if err != nil {
		panic(err)
	}
	log.Printf("Lambda function %v added to user pool %v to handle the PreSignUp trigger.\n",
		functionArn, userPoolId)
}

// SignUpUser signs up a user from the known user table with a password you specify.
func (runner *AutoConfirm) SignUpUser(ctx context.Context, clientId string, usersTable string) (string, string) {
	log.Println("Let's sign up a user to your Cognito user pool. When the user's email matches an email in the\n" +
		"DynamoDB known users table, it is automatically verified and the user is confirmed.")

	knownUsers, err := runner.helper.GetKnownUsers(ctx, usersTable)
	if err != nil {
		panic(err)
	}
	userChoice := runner.questioner.AskChoice("Which user do you want to use?\n", knownUsers.UserNameList())
	user := knownUsers.Users[userChoice]

	var signedUp bool
	var userConfirmed bool
	password := runner.questioner.AskPassword("Enter a password that has at least eight characters, uppercase, lowercase, numbers and symbols.\n"+
		"(the password will not display as you type):", 8)
	for !signedUp {
		log.Printf("Signing up user '%v' with email '%v' to Cognito.\n", user.UserName, user.UserEmail)
		userConfirmed, err = runner.cognitoActor.SignUp(ctx, clientId, user.UserName, password, user.UserEmail)
		if err != nil {
			var invalidPassword *types.InvalidPasswordException
			if errors.As(err, &invalidPassword) {
				password = runner.questioner.AskPassword("Enter another password:", 8)
			} else {
				panic(err)
			}
		} else {
			signedUp = true
		}
	}
	log.Printf("User %v signed up, confirmed = %v.\n", user.UserName, userConfirmed)

	log.Println(strings.Repeat("-", 88))

	return user.UserName, password
}

// SignInUser signs in a user.
func (runner *AutoConfirm) SignInUser(ctx context.Context, clientId string, userName string, password string) string {
	runner.questioner.Ask("Press Enter when you're ready to continue.")
	log.Printf("Let's sign in as %v...\n", userName)
	authResult, err := runner.cognitoActor.SignIn(ctx, clientId, userName, password)
	if err != nil {
		panic(err)
	}
	log.Printf("Successfully signed in. Your access token starts with: %v...\n", (*authResult.AccessToken)[:10])
	log.Println(strings.Repeat("-", 88))
	return *authResult.AccessToken
}

// Run runs the scenario.
func (runner *AutoConfirm) Run(ctx context.Context, stackName string) {
	defer func() {
		if r := recover(); r != nil {
			log.Println("Something went wrong with the demo.")
			runner.resources.Cleanup(ctx)
		}
	}()

	log.Println(strings.Repeat("-", 88))
	log.Printf("Welcome\n")

	log.Println(strings.Repeat("-", 88))

	stackOutputs, err := runner.helper.GetStackOutputs(ctx, stackName)
	if err != nil {
		panic(err)
	}
	runner.resources.userPoolId = stackOutputs["UserPoolId"]
	runner.helper.PopulateUserTable(ctx, stackOutputs["TableName"])

	runner.AddPreSignUpTrigger(ctx, stackOutputs["UserPoolId"], stackOutputs["AutoConfirmFunctionArn"])
	runner.resources.triggers = append(runner.resources.triggers, actions.PreSignUp)
	userName, password := runner.SignUpUser(ctx, stackOutputs["UserPoolClientId"], stackOutputs["TableName"])
	runner.helper.ListRecentLogEvents(ctx, stackOutputs["AutoConfirmFunction"])
	runner.resources.userAccessTokens = append(runner.resources.userAccessTokens,
		runner.SignInUser(ctx, stackOutputs["UserPoolClientId"], userName, password))

	runner.resources.Cleanup(ctx)

	log.Println(strings.Repeat("-", 88))
	log.Println("Thanks for watching!")
	log.Println(strings.Repeat("-", 88))
}
```
Behandeln Sie den `PreSignUp`-Trigger mit einer Lambda-Funktion.  

```
import (
	"context"
	"log"
	"os"

	"github.com/aws/aws-lambda-go/events"
	"github.com/aws/aws-lambda-go/lambda"
	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/config"
	"github.com/aws/aws-sdk-go-v2/feature/dynamodb/attributevalue"
	"github.com/aws/aws-sdk-go-v2/service/dynamodb"
	dynamodbtypes "github.com/aws/aws-sdk-go-v2/service/dynamodb/types"
)

const TABLE_NAME = "TABLE_NAME"

// UserInfo defines structured user data that can be marshalled to a DynamoDB format.
type UserInfo struct {
	UserName  string `dynamodbav:"UserName"`
	UserEmail string `dynamodbav:"UserEmail"`
}

// GetKey marshals the user email value to a DynamoDB key format.
func (user UserInfo) GetKey() map[string]dynamodbtypes.AttributeValue {
	userEmail, err := attributevalue.Marshal(user.UserEmail)
	if err != nil {
		panic(err)
	}
	return map[string]dynamodbtypes.AttributeValue{"UserEmail": userEmail}
}

type handler struct {
	dynamoClient *dynamodb.Client
}

// HandleRequest handles the PreSignUp event by looking up a user in an Amazon DynamoDB table and
// specifying whether they should be confirmed and verified.
func (h *handler) HandleRequest(ctx context.Context, event events.CognitoEventUserPoolsPreSignup) (events.CognitoEventUserPoolsPreSignup, error) {
	log.Printf("Received presignup from %v for user '%v'", event.TriggerSource, event.UserName)
	if event.TriggerSource != "PreSignUp_SignUp" {
		// Other trigger sources, such as PreSignUp_AdminInitiateAuth, ignore the response from this handler.
		return event, nil
	}
	tableName := os.Getenv(TABLE_NAME)
	user := UserInfo{
		UserEmail: event.Request.UserAttributes["email"],
	}
	log.Printf("Looking up email %v in table %v.\n", user.UserEmail, tableName)
	output, err := h.dynamoClient.GetItem(ctx, &dynamodb.GetItemInput{
		Key:       user.GetKey(),
		TableName: aws.String(tableName),
	})
	if err != nil {
		log.Printf("Error looking up email %v.\n", user.UserEmail)
		return event, err
	}
	if output.Item == nil {
		log.Printf("Email %v not found. Email verification is required.\n", user.UserEmail)
		return event, err
	}

	err = attributevalue.UnmarshalMap(output.Item, &user)
	if err != nil {
		log.Printf("Couldn't unmarshal DynamoDB item. Here's why: %v\n", err)
		return event, err
	}

	if user.UserName != event.UserName {
		log.Printf("UserEmail %v found, but stored UserName '%v' does not match supplied UserName '%v'. Verification is required.\n",
			user.UserEmail, user.UserName, event.UserName)
	} else {
		log.Printf("UserEmail %v found with matching UserName %v. User is confirmed.\n", user.UserEmail, user.UserName)
		event.Response.AutoConfirmUser = true
		event.Response.AutoVerifyEmail = true
	}

	return event, err
}

func main() {
	ctx := context.Background()
	sdkConfig, err := config.LoadDefaultConfig(ctx)
	if err != nil {
		log.Panicln(err)
	}
	h := handler{
		dynamoClient: dynamodb.NewFromConfig(sdkConfig),
	}
	lambda.Start(h.HandleRequest)
}
```
Erstellen Sie eine Struktur, die allgemeine Aufgaben ausführt.  

```
import (
	"context"
	"log"
	"strings"
	"time"
	"user_pools_and_lambda_triggers/actions"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cloudformation"
	"github.com/aws/aws-sdk-go-v2/service/cloudwatchlogs"
	"github.com/aws/aws-sdk-go-v2/service/dynamodb"
	"github.com/awsdocs/aws-doc-sdk-examples/gov2/demotools"
)

// IScenarioHelper defines common functions used by the workflows in this example.
type IScenarioHelper interface {
	Pause(secs int)
	GetStackOutputs(ctx context.Context, stackName string) (actions.StackOutputs, error)
	PopulateUserTable(ctx context.Context, tableName string)
	GetKnownUsers(ctx context.Context, tableName string) (actions.UserList, error)
	AddKnownUser(ctx context.Context, tableName string, user actions.User)
	ListRecentLogEvents(ctx context.Context, functionName string)
}

// ScenarioHelper contains AWS wrapper structs used by the workflows in this example.
type ScenarioHelper struct {
	questioner  demotools.IQuestioner
	dynamoActor *actions.DynamoActions
	cfnActor    *actions.CloudFormationActions
	cwlActor    *actions.CloudWatchLogsActions
	isTestRun   bool
}

// NewScenarioHelper constructs a new scenario helper.
func NewScenarioHelper(sdkConfig aws.Config, questioner demotools.IQuestioner) ScenarioHelper {
	scenario := ScenarioHelper{
		questioner:  questioner,
		dynamoActor: &actions.DynamoActions{DynamoClient: dynamodb.NewFromConfig(sdkConfig)},
		cfnActor:    &actions.CloudFormationActions{CfnClient: cloudformation.NewFromConfig(sdkConfig)},
		cwlActor:    &actions.CloudWatchLogsActions{CwlClient: cloudwatchlogs.NewFromConfig(sdkConfig)},
	}
	return scenario
}

// Pause waits for the specified number of seconds.
func (helper ScenarioHelper) Pause(secs int) {
	if !helper.isTestRun {
		time.Sleep(time.Duration(secs) * time.Second)
	}
}

// GetStackOutputs gets the outputs from the specified CloudFormation stack in a structured format.
func (helper ScenarioHelper) GetStackOutputs(ctx context.Context, stackName string) (actions.StackOutputs, error) {
	return helper.cfnActor.GetOutputs(ctx, stackName), nil
}

// PopulateUserTable fills the known user table with example data.
func (helper ScenarioHelper) PopulateUserTable(ctx context.Context, tableName string) {
	log.Printf("First, let's add some users to the DynamoDB %v table we'll use for this example.\n", tableName)
	err := helper.dynamoActor.PopulateTable(ctx, tableName)
	if err != nil {
		panic(err)
	}
}

// GetKnownUsers gets the users from the known users table in a structured format.
func (helper ScenarioHelper) GetKnownUsers(ctx context.Context, tableName string) (actions.UserList, error) {
	knownUsers, err := helper.dynamoActor.Scan(ctx, tableName)
	if err != nil {
		log.Printf("Couldn't get known users from table %v. Here's why: %v\n", tableName, err)
	}
	return knownUsers, err
}

// AddKnownUser adds a user to the known users table.
func (helper ScenarioHelper) AddKnownUser(ctx context.Context, tableName string, user actions.User) {
	log.Printf("Adding user '%v' with email '%v' to the DynamoDB known users table...\n",
		user.UserName, user.UserEmail)
	err := helper.dynamoActor.AddUser(ctx, tableName, user)
	if err != nil {
		panic(err)
	}
}

// ListRecentLogEvents gets the most recent log stream and events for the specified Lambda function and displays them.
func (helper ScenarioHelper) ListRecentLogEvents(ctx context.Context, functionName string) {
	log.Println("Waiting a few seconds to let Lambda write to CloudWatch Logs...")
	helper.Pause(10)
	log.Println("Okay, let's check the logs to find what's happened recently with your Lambda function.")
	logStream, err := helper.cwlActor.GetLatestLogStream(ctx, functionName)
	if err != nil {
		panic(err)
	}
	log.Printf("Getting some recent events from log stream %v\n", *logStream.LogStreamName)
	events, err := helper.cwlActor.GetLogEvents(ctx, functionName, *logStream.LogStreamName, 10)
	if err != nil {
		panic(err)
	}
	for _, event := range events {
		log.Printf("\t%v", *event.Message)
	}
	log.Println(strings.Repeat("-", 88))
}
```
Erstellen Sie eine Struktur, die Amazon Cognito-Aktionen umschließt.  

```
import (
	"context"
	"errors"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider/types"
)

type CognitoActions struct {
	CognitoClient *cognitoidentityprovider.Client
}



// Trigger and TriggerInfo define typed data for updating an Amazon Cognito trigger.
type Trigger int

const (
	PreSignUp Trigger = iota
	UserMigration
	PostAuthentication
)

type TriggerInfo struct {
	Trigger    Trigger
	HandlerArn *string
}

// UpdateTriggers adds or removes Lambda triggers for a user pool. When a trigger is specified with a `nil` value,
// it is removed from the user pool.
func (actor CognitoActions) UpdateTriggers(ctx context.Context, userPoolId string, triggers ...TriggerInfo) error {
	output, err := actor.CognitoClient.DescribeUserPool(ctx, &cognitoidentityprovider.DescribeUserPoolInput{
		UserPoolId: aws.String(userPoolId),
	})
	if err != nil {
		log.Printf("Couldn't get info about user pool %v. Here's why: %v\n", userPoolId, err)
		return err
	}
	lambdaConfig := output.UserPool.LambdaConfig
	for _, trigger := range triggers {
		switch trigger.Trigger {
		case PreSignUp:
			lambdaConfig.PreSignUp = trigger.HandlerArn
		case UserMigration:
			lambdaConfig.UserMigration = trigger.HandlerArn
		case PostAuthentication:
			lambdaConfig.PostAuthentication = trigger.HandlerArn
		}
	}
	_, err = actor.CognitoClient.UpdateUserPool(ctx, &cognitoidentityprovider.UpdateUserPoolInput{
		UserPoolId:   aws.String(userPoolId),
		LambdaConfig: lambdaConfig,
	})
	if err != nil {
		log.Printf("Couldn't update user pool %v. Here's why: %v\n", userPoolId, err)
	}
	return err
}



// SignUp signs up a user with Amazon Cognito.
func (actor CognitoActions) SignUp(ctx context.Context, clientId string, userName string, password string, userEmail string) (bool, error) {
	confirmed := false
	output, err := actor.CognitoClient.SignUp(ctx, &cognitoidentityprovider.SignUpInput{
		ClientId: aws.String(clientId),
		Password: aws.String(password),
		Username: aws.String(userName),
		UserAttributes: []types.AttributeType{
			{Name: aws.String("email"), Value: aws.String(userEmail)},
		},
	})
	if err != nil {
		var invalidPassword *types.InvalidPasswordException
		if errors.As(err, &invalidPassword) {
			log.Println(*invalidPassword.Message)
		} else {
			log.Printf("Couldn't sign up user %v. Here's why: %v\n", userName, err)
		}
	} else {
		confirmed = output.UserConfirmed
	}
	return confirmed, err
}



// SignIn signs in a user to Amazon Cognito using a username and password authentication flow.
func (actor CognitoActions) SignIn(ctx context.Context, clientId string, userName string, password string) (*types.AuthenticationResultType, error) {
	var authResult *types.AuthenticationResultType
	output, err := actor.CognitoClient.InitiateAuth(ctx, &cognitoidentityprovider.InitiateAuthInput{
		AuthFlow:       "USER_PASSWORD_AUTH",
		ClientId:       aws.String(clientId),
		AuthParameters: map[string]string{"USERNAME": userName, "PASSWORD": password},
	})
	if err != nil {
		var resetRequired *types.PasswordResetRequiredException
		if errors.As(err, &resetRequired) {
			log.Println(*resetRequired.Message)
		} else {
			log.Printf("Couldn't sign in user %v. Here's why: %v\n", userName, err)
		}
	} else {
		authResult = output.AuthenticationResult
	}
	return authResult, err
}



// ForgotPassword starts a password recovery flow for a user. This flow typically sends a confirmation code
// to the user's configured notification destination, such as email.
func (actor CognitoActions) ForgotPassword(ctx context.Context, clientId string, userName string) (*types.CodeDeliveryDetailsType, error) {
	output, err := actor.CognitoClient.ForgotPassword(ctx, &cognitoidentityprovider.ForgotPasswordInput{
		ClientId: aws.String(clientId),
		Username: aws.String(userName),
	})
	if err != nil {
		log.Printf("Couldn't start password reset for user '%v'. Here;s why: %v\n", userName, err)
	}
	return output.CodeDeliveryDetails, err
}



// ConfirmForgotPassword confirms a user with a confirmation code and a new password.
func (actor CognitoActions) ConfirmForgotPassword(ctx context.Context, clientId string, code string, userName string, password string) error {
	_, err := actor.CognitoClient.ConfirmForgotPassword(ctx, &cognitoidentityprovider.ConfirmForgotPasswordInput{
		ClientId:         aws.String(clientId),
		ConfirmationCode: aws.String(code),
		Password:         aws.String(password),
		Username:         aws.String(userName),
	})
	if err != nil {
		var invalidPassword *types.InvalidPasswordException
		if errors.As(err, &invalidPassword) {
			log.Println(*invalidPassword.Message)
		} else {
			log.Printf("Couldn't confirm user %v. Here's why: %v", userName, err)
		}
	}
	return err
}



// DeleteUser removes a user from the user pool.
func (actor CognitoActions) DeleteUser(ctx context.Context, userAccessToken string) error {
	_, err := actor.CognitoClient.DeleteUser(ctx, &cognitoidentityprovider.DeleteUserInput{
		AccessToken: aws.String(userAccessToken),
	})
	if err != nil {
		log.Printf("Couldn't delete user. Here's why: %v\n", err)
	}
	return err
}



// AdminCreateUser uses administrator credentials to add a user to a user pool. This method leaves the user
// in a state that requires they enter a new password next time they sign in.
func (actor CognitoActions) AdminCreateUser(ctx context.Context, userPoolId string, userName string, userEmail string) error {
	_, err := actor.CognitoClient.AdminCreateUser(ctx, &cognitoidentityprovider.AdminCreateUserInput{
		UserPoolId:     aws.String(userPoolId),
		Username:       aws.String(userName),
		MessageAction:  types.MessageActionTypeSuppress,
		UserAttributes: []types.AttributeType{{Name: aws.String("email"), Value: aws.String(userEmail)}},
	})
	if err != nil {
		var userExists *types.UsernameExistsException
		if errors.As(err, &userExists) {
			log.Printf("User %v already exists in the user pool.", userName)
			err = nil
		} else {
			log.Printf("Couldn't create user %v. Here's why: %v\n", userName, err)
		}
	}
	return err
}



// AdminSetUserPassword uses administrator credentials to set a password for a user without requiring a
// temporary password.
func (actor CognitoActions) AdminSetUserPassword(ctx context.Context, userPoolId string, userName string, password string) error {
	_, err := actor.CognitoClient.AdminSetUserPassword(ctx, &cognitoidentityprovider.AdminSetUserPasswordInput{
		Password:   aws.String(password),
		UserPoolId: aws.String(userPoolId),
		Username:   aws.String(userName),
		Permanent:  true,
	})
	if err != nil {
		var invalidPassword *types.InvalidPasswordException
		if errors.As(err, &invalidPassword) {
			log.Println(*invalidPassword.Message)
		} else {
			log.Printf("Couldn't set password for user %v. Here's why: %v\n", userName, err)
		}
	}
	return err
}
```
Erstellen Sie eine Struktur, die DynamoDB-Aktionen umhüllt.  

```
import (
	"context"
	"fmt"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/feature/dynamodb/attributevalue"
	"github.com/aws/aws-sdk-go-v2/service/dynamodb"
	"github.com/aws/aws-sdk-go-v2/service/dynamodb/types"
)

// DynamoActions encapsulates the Amazon Simple Notification Service (Amazon SNS) actions
// used in the examples.
type DynamoActions struct {
	DynamoClient *dynamodb.Client
}

// User defines structured user data.
type User struct {
	UserName  string
	UserEmail string
	LastLogin *LoginInfo `dynamodbav:",omitempty"`
}

// LoginInfo defines structured custom login data.
type LoginInfo struct {
	UserPoolId string
	ClientId   string
	Time       string
}

// UserList defines a list of users.
type UserList struct {
	Users []User
}

// UserNameList returns the usernames contained in a UserList as a list of strings.
func (users *UserList) UserNameList() []string {
	names := make([]string, len(users.Users))
	for i := 0; i < len(users.Users); i++ {
		names[i] = users.Users[i].UserName
	}
	return names
}

// PopulateTable adds a set of test users to the table.
func (actor DynamoActions) PopulateTable(ctx context.Context, tableName string) error {
	var err error
	var item map[string]types.AttributeValue
	var writeReqs []types.WriteRequest
	for i := 1; i < 4; i++ {
		item, err = attributevalue.MarshalMap(User{UserName: fmt.Sprintf("test_user_%v", i), UserEmail: fmt.Sprintf("test_email_%v@example.com", i)})
		if err != nil {
			log.Printf("Couldn't marshall user into DynamoDB format. Here's why: %v\n", err)
			return err
		}
		writeReqs = append(writeReqs, types.WriteRequest{PutRequest: &types.PutRequest{Item: item}})
	}
	_, err = actor.DynamoClient.BatchWriteItem(ctx, &dynamodb.BatchWriteItemInput{
		RequestItems: map[string][]types.WriteRequest{tableName: writeReqs},
	})
	if err != nil {
		log.Printf("Couldn't populate table %v with users. Here's why: %v\n", tableName, err)
	}
	return err
}

// Scan scans the table for all items.
func (actor DynamoActions) Scan(ctx context.Context, tableName string) (UserList, error) {
	var userList UserList
	output, err := actor.DynamoClient.Scan(ctx, &dynamodb.ScanInput{
		TableName: aws.String(tableName),
	})
	if err != nil {
		log.Printf("Couldn't scan table %v for items. Here's why: %v\n", tableName, err)
	} else {
		err = attributevalue.UnmarshalListOfMaps(output.Items, &userList.Users)
		if err != nil {
			log.Printf("Couldn't unmarshal items into users. Here's why: %v\n", err)
		}
	}
	return userList, err
}

// AddUser adds a user item to a table.
func (actor DynamoActions) AddUser(ctx context.Context, tableName string, user User) error {
	userItem, err := attributevalue.MarshalMap(user)
	if err != nil {
		log.Printf("Couldn't marshall user to item. Here's why: %v\n", err)
	}
	_, err = actor.DynamoClient.PutItem(ctx, &dynamodb.PutItemInput{
		Item:      userItem,
		TableName: aws.String(tableName),
	})
	if err != nil {
		log.Printf("Couldn't put item in table %v. Here's why: %v", tableName, err)
	}
	return err
}
```
Erstellen Sie eine Struktur, die CloudWatch Logs-Aktionen umschließt.  

```
import (
	"context"
	"fmt"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cloudwatchlogs"
	"github.com/aws/aws-sdk-go-v2/service/cloudwatchlogs/types"
)

type CloudWatchLogsActions struct {
	CwlClient *cloudwatchlogs.Client
}

// GetLatestLogStream gets the most recent log stream for a Lambda function.
func (actor CloudWatchLogsActions) GetLatestLogStream(ctx context.Context, functionName string) (types.LogStream, error) {
	var logStream types.LogStream
	logGroupName := fmt.Sprintf("/aws/lambda/%s", functionName)
	output, err := actor.CwlClient.DescribeLogStreams(ctx, &cloudwatchlogs.DescribeLogStreamsInput{
		Descending:   aws.Bool(true),
		Limit:        aws.Int32(1),
		LogGroupName: aws.String(logGroupName),
		OrderBy:      types.OrderByLastEventTime,
	})
	if err != nil {
		log.Printf("Couldn't get log streams for log group %v. Here's why: %v\n", logGroupName, err)
	} else {
		logStream = output.LogStreams[0]
	}
	return logStream, err
}

// GetLogEvents gets the most recent eventCount events from the specified log stream.
func (actor CloudWatchLogsActions) GetLogEvents(ctx context.Context, functionName string, logStreamName string, eventCount int32) (
	[]types.OutputLogEvent, error) {
	var events []types.OutputLogEvent
	logGroupName := fmt.Sprintf("/aws/lambda/%s", functionName)
	output, err := actor.CwlClient.GetLogEvents(ctx, &cloudwatchlogs.GetLogEventsInput{
		LogStreamName: aws.String(logStreamName),
		Limit:         aws.Int32(eventCount),
		LogGroupName:  aws.String(logGroupName),
	})
	if err != nil {
		log.Printf("Couldn't get log event for log stream %v. Here's why: %v\n", logStreamName, err)
	} else {
		events = output.Events
	}
	return events, err
}
```
Erstellen Sie eine Struktur, die Aktionen umschließt. CloudFormation   

```
import (
	"context"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cloudformation"
)

// StackOutputs defines a map of outputs from a specific stack.
type StackOutputs map[string]string

type CloudFormationActions struct {
	CfnClient *cloudformation.Client
}

// GetOutputs gets the outputs from a CloudFormation stack and puts them into a structured format.
func (actor CloudFormationActions) GetOutputs(ctx context.Context, stackName string) StackOutputs {
	output, err := actor.CfnClient.DescribeStacks(ctx, &cloudformation.DescribeStacksInput{
		StackName: aws.String(stackName),
	})
	if err != nil || len(output.Stacks) == 0 {
		log.Panicf("Couldn't find a CloudFormation stack named %v. Here's why: %v\n", stackName, err)
	}
	stackOutputs := StackOutputs{}
	for _, out := range output.Stacks[0].Outputs {
		stackOutputs[*out.OutputKey] = *out.OutputValue
	}
	return stackOutputs
}
```
Bereinigen von Ressourcen.  

```
import (
	"context"
	"log"
	"user_pools_and_lambda_triggers/actions"

	"github.com/awsdocs/aws-doc-sdk-examples/gov2/demotools"
)

// Resources keeps track of AWS resources created during an example and handles
// cleanup when the example finishes.
type Resources struct {
	userPoolId       string
	userAccessTokens []string
	triggers         []actions.Trigger

	cognitoActor *actions.CognitoActions
	questioner   demotools.IQuestioner
}

func (resources *Resources) init(cognitoActor *actions.CognitoActions, questioner demotools.IQuestioner) {
	resources.userAccessTokens = []string{}
	resources.triggers = []actions.Trigger{}
	resources.cognitoActor = cognitoActor
	resources.questioner = questioner
}

// Cleanup deletes all AWS resources created during an example.
func (resources *Resources) Cleanup(ctx context.Context) {
	defer func() {
		if r := recover(); r != nil {
			log.Printf("Something went wrong during cleanup.\n%v\n", r)
			log.Println("Use the AWS Management Console to remove any remaining resources \n" +
				"that were created for this scenario.")
		}
	}()

	wantDelete := resources.questioner.AskBool("Do you want to remove all of the AWS resources that were created "+
		"during this demo (y/n)?", "y")
	if wantDelete {
		for _, accessToken := range resources.userAccessTokens {
			err := resources.cognitoActor.DeleteUser(ctx, accessToken)
			if err != nil {
				log.Println("Couldn't delete user during cleanup.")
				panic(err)
			}
			log.Println("Deleted user.")
		}
		triggerList := make([]actions.TriggerInfo, len(resources.triggers))
		for i := 0; i < len(resources.triggers); i++ {
			triggerList[i] = actions.TriggerInfo{Trigger: resources.triggers[i], HandlerArn: nil}
		}
		err := resources.cognitoActor.UpdateTriggers(ctx, resources.userPoolId, triggerList...)
		if err != nil {
			log.Println("Couldn't update Cognito triggers during cleanup.")
			panic(err)
		}
		log.Println("Removed Cognito triggers from user pool.")
	} else {
		log.Println("Be sure to remove resources when you're done with them to avoid unexpected charges!")
	}
}
```
+ Weitere API-Informationen finden Sie in den folgenden Themen der *AWS SDK für Go -API-Referenz*.
  + [DeleteUser](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.DeleteUser)
  + [InitiateAuth](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.InitiateAuth)
  + [SignUp](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.SignUp)
  + [UpdateUserPool](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.UpdateUserPool)

### Migrieren Sie automatisch bekannte Benutzer mit einer Lambda-Funktion
<a name="cross_CognitoAutoMigrateUser_go_2_topic"></a>

Das folgende Codebeispiel zeigt, wie bekannte Amazon Cognito-Benutzer mit einer Lambda-Funktion automatisch migriert werden können.
+ Konfigurieren Sie einen Benutzerpool, um eine Lambda-Funktion für den `MigrateUser`-Trigger aufzurufen.
+ Melden Sie sich bei Amazon Cognito mit einem Benutzernamen und einer E-Mail-Adresse an, die sich nicht im Benutzerpool befinden.
+ Die Lambda-Funktion durchsucht eine DynamoDB-Tabelle und migriert bekannte Benutzer automatisch in den Benutzerpool.
+ Führen Sie den Ablauf „Passwort vergessen“ aus, um das Passwort für den migrierten Benutzer zurückzusetzen.
+ Melden Sie sich als neuer Benutzer an und bereinigen Sie dann die Ressourcen.

**SDK für Go V2**  
 Es gibt noch mehr dazu. GitHub Hier finden Sie das vollständige Beispiel und erfahren, wie Sie das [AWS -Code-Beispiel-](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/gov2/workflows/user_pools_and_lambda_triggers#code-examples) einrichten und ausführen. 
Führen Sie ein interaktives Szenario an einem Prompt aus.  

```
import (
	"context"
	"errors"
	"fmt"
	"log"
	"strings"
	"user_pools_and_lambda_triggers/actions"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider/types"
	"github.com/awsdocs/aws-doc-sdk-examples/gov2/demotools"
)

// MigrateUser separates the steps of this scenario into individual functions so that
// they are simpler to read and understand.
type MigrateUser struct {
	helper       IScenarioHelper
	questioner   demotools.IQuestioner
	resources    Resources
	cognitoActor *actions.CognitoActions
}

// NewMigrateUser constructs a new migrate user runner.
func NewMigrateUser(sdkConfig aws.Config, questioner demotools.IQuestioner, helper IScenarioHelper) MigrateUser {
	scenario := MigrateUser{
		helper:       helper,
		questioner:   questioner,
		resources:    Resources{},
		cognitoActor: &actions.CognitoActions{CognitoClient: cognitoidentityprovider.NewFromConfig(sdkConfig)},
	}
	scenario.resources.init(scenario.cognitoActor, questioner)
	return scenario
}

// AddMigrateUserTrigger adds a Lambda handler as an invocation target for the MigrateUser trigger.
func (runner *MigrateUser) AddMigrateUserTrigger(ctx context.Context, userPoolId string, functionArn string) {
	log.Printf("Let's add a Lambda function to handle the MigrateUser trigger from Cognito.\n" +
		"This trigger happens when an unknown user signs in, and lets your function take action before Cognito\n" +
		"rejects the user.\n\n")
	err := runner.cognitoActor.UpdateTriggers(
		ctx, userPoolId,
		actions.TriggerInfo{Trigger: actions.UserMigration, HandlerArn: aws.String(functionArn)})
	if err != nil {
		panic(err)
	}
	log.Printf("Lambda function %v added to user pool %v to handle the MigrateUser trigger.\n",
		functionArn, userPoolId)

	log.Println(strings.Repeat("-", 88))
}

// SignInUser adds a new user to the known users table and signs that user in to Amazon Cognito.
func (runner *MigrateUser) SignInUser(ctx context.Context, usersTable string, clientId string) (bool, actions.User) {
	log.Println("Let's sign in a user to your Cognito user pool. When the username and email matches an entry in the\n" +
		"DynamoDB known users table, the email is automatically verified and the user is migrated to the Cognito user pool.")

	user := actions.User{}
	user.UserName = runner.questioner.Ask("\nEnter a username:")
	user.UserEmail = runner.questioner.Ask("\nEnter an email that you own. This email will be used to confirm user migration\n" +
		"during this example:")

	runner.helper.AddKnownUser(ctx, usersTable, user)

	var err error
	var resetRequired *types.PasswordResetRequiredException
	var authResult *types.AuthenticationResultType
	signedIn := false
	for !signedIn && resetRequired == nil {
		log.Printf("Signing in to Cognito as user '%v'. The expected result is a PasswordResetRequiredException.\n\n", user.UserName)
		authResult, err = runner.cognitoActor.SignIn(ctx, clientId, user.UserName, "_")
		if err != nil {
			if errors.As(err, &resetRequired) {
				log.Printf("\nUser '%v' is not in the Cognito user pool but was found in the DynamoDB known users table.\n"+
					"User migration is started and a password reset is required.", user.UserName)
			} else {
				panic(err)
			}
		} else {
			log.Printf("User '%v' successfully signed in. This is unexpected and probably means you have not\n"+
				"cleaned up a previous run of this scenario, so the user exist in the Cognito user pool.\n"+
				"You can continue this example and select to clean up resources, or manually remove\n"+
				"the user from your user pool and try again.", user.UserName)
			runner.resources.userAccessTokens = append(runner.resources.userAccessTokens, *authResult.AccessToken)
			signedIn = true
		}
	}

	log.Println(strings.Repeat("-", 88))
	return resetRequired != nil, user
}

// ResetPassword starts a password recovery flow.
func (runner *MigrateUser) ResetPassword(ctx context.Context, clientId string, user actions.User) {
	wantCode := runner.questioner.AskBool(fmt.Sprintf("In order to migrate the user to Cognito, you must be able to receive a confirmation\n"+
		"code by email at %v. Do you want to send a code (y/n)?", user.UserEmail), "y")
	if !wantCode {
		log.Println("To complete this example and successfully migrate a user to Cognito, you must enter an email\n" +
			"you own that can receive a confirmation code.")
		return
	}
	codeDelivery, err := runner.cognitoActor.ForgotPassword(ctx, clientId, user.UserName)
	if err != nil {
		panic(err)
	}
	log.Printf("\nA confirmation code has been sent to %v.", *codeDelivery.Destination)
	code := runner.questioner.Ask("Check your email and enter it here:")

	confirmed := false
	password := runner.questioner.AskPassword("\nEnter a password that has at least eight characters, uppercase, lowercase, numbers and symbols.\n"+
		"(the password will not display as you type):", 8)
	for !confirmed {
		log.Printf("\nConfirming password reset for user '%v'.\n", user.UserName)
		err = runner.cognitoActor.ConfirmForgotPassword(ctx, clientId, code, user.UserName, password)
		if err != nil {
			var invalidPassword *types.InvalidPasswordException
			if errors.As(err, &invalidPassword) {
				password = runner.questioner.AskPassword("\nEnter another password:", 8)
			} else {
				panic(err)
			}
		} else {
			confirmed = true
		}
	}
	log.Printf("User '%v' successfully confirmed and migrated.\n", user.UserName)
	log.Println("Signing in with your username and password...")
	authResult, err := runner.cognitoActor.SignIn(ctx, clientId, user.UserName, password)
	if err != nil {
		panic(err)
	}
	log.Printf("Successfully signed in. Your access token starts with: %v...\n", (*authResult.AccessToken)[:10])
	runner.resources.userAccessTokens = append(runner.resources.userAccessTokens, *authResult.AccessToken)

	log.Println(strings.Repeat("-", 88))
}

// Run runs the scenario.
func (runner *MigrateUser) Run(ctx context.Context, stackName string) {
	defer func() {
		if r := recover(); r != nil {
			log.Println("Something went wrong with the demo.")
			runner.resources.Cleanup(ctx)
		}
	}()

	log.Println(strings.Repeat("-", 88))
	log.Printf("Welcome\n")

	log.Println(strings.Repeat("-", 88))

	stackOutputs, err := runner.helper.GetStackOutputs(ctx, stackName)
	if err != nil {
		panic(err)
	}
	runner.resources.userPoolId = stackOutputs["UserPoolId"]

	runner.AddMigrateUserTrigger(ctx, stackOutputs["UserPoolId"], stackOutputs["MigrateUserFunctionArn"])
	runner.resources.triggers = append(runner.resources.triggers, actions.UserMigration)
	resetNeeded, user := runner.SignInUser(ctx, stackOutputs["TableName"], stackOutputs["UserPoolClientId"])
	if resetNeeded {
		runner.helper.ListRecentLogEvents(ctx, stackOutputs["MigrateUserFunction"])
		runner.ResetPassword(ctx, stackOutputs["UserPoolClientId"], user)
	}

	runner.resources.Cleanup(ctx)

	log.Println(strings.Repeat("-", 88))
	log.Println("Thanks for watching!")
	log.Println(strings.Repeat("-", 88))
}
```
Behandeln Sie den `MigrateUser`-Trigger mit einer Lambda-Funktion.  

```
import (
	"context"
	"log"
	"os"

	"github.com/aws/aws-lambda-go/events"
	"github.com/aws/aws-lambda-go/lambda"
	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/config"
	"github.com/aws/aws-sdk-go-v2/feature/dynamodb/attributevalue"
	"github.com/aws/aws-sdk-go-v2/feature/dynamodb/expression"
	"github.com/aws/aws-sdk-go-v2/service/dynamodb"
)

const TABLE_NAME = "TABLE_NAME"

// UserInfo defines structured user data that can be marshalled to a DynamoDB format.
type UserInfo struct {
	UserName  string `dynamodbav:"UserName"`
	UserEmail string `dynamodbav:"UserEmail"`
}

type handler struct {
	dynamoClient *dynamodb.Client
}

// HandleRequest handles the MigrateUser event by looking up a user in an Amazon DynamoDB table and
// specifying whether they should be migrated to the user pool.
func (h *handler) HandleRequest(ctx context.Context, event events.CognitoEventUserPoolsMigrateUser) (events.CognitoEventUserPoolsMigrateUser, error) {
	log.Printf("Received migrate trigger from %v for user '%v'", event.TriggerSource, event.UserName)
	if event.TriggerSource != "UserMigration_Authentication" {
		return event, nil
	}
	tableName := os.Getenv(TABLE_NAME)
	user := UserInfo{
		UserName: event.UserName,
	}
	log.Printf("Looking up user '%v' in table %v.\n", user.UserName, tableName)
	filterEx := expression.Name("UserName").Equal(expression.Value(user.UserName))
	expr, err := expression.NewBuilder().WithFilter(filterEx).Build()
	if err != nil {
		log.Printf("Error building expression to query for user '%v'.\n", user.UserName)
		return event, err
	}
	output, err := h.dynamoClient.Scan(ctx, &dynamodb.ScanInput{
		TableName:                 aws.String(tableName),
		FilterExpression:          expr.Filter(),
		ExpressionAttributeNames:  expr.Names(),
		ExpressionAttributeValues: expr.Values(),
	})
	if err != nil {
		log.Printf("Error looking up user '%v'.\n", user.UserName)
		return event, err
	}
	if len(output.Items) == 0 {
		log.Printf("User '%v' not found, not migrating user.\n", user.UserName)
		return event, err
	}

	var users []UserInfo
	err = attributevalue.UnmarshalListOfMaps(output.Items, &users)
	if err != nil {
		log.Printf("Couldn't unmarshal DynamoDB items. Here's why: %v\n", err)
		return event, err
	}

	user = users[0]
	log.Printf("UserName '%v' found with email %v. User is migrated and must reset password.\n", user.UserName, user.UserEmail)
	event.CognitoEventUserPoolsMigrateUserResponse.UserAttributes = map[string]string{
		"email":          user.UserEmail,
		"email_verified": "true", // email_verified is required for the forgot password flow.
	}
	event.CognitoEventUserPoolsMigrateUserResponse.FinalUserStatus = "RESET_REQUIRED"
	event.CognitoEventUserPoolsMigrateUserResponse.MessageAction = "SUPPRESS"

	return event, err
}

func main() {
	ctx := context.Background()
	sdkConfig, err := config.LoadDefaultConfig(ctx)
	if err != nil {
		log.Panicln(err)
	}
	h := handler{
		dynamoClient: dynamodb.NewFromConfig(sdkConfig),
	}
	lambda.Start(h.HandleRequest)
}
```
Erstellen Sie eine Struktur, die allgemeine Aufgaben ausführt.  

```
import (
	"context"
	"log"
	"strings"
	"time"
	"user_pools_and_lambda_triggers/actions"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cloudformation"
	"github.com/aws/aws-sdk-go-v2/service/cloudwatchlogs"
	"github.com/aws/aws-sdk-go-v2/service/dynamodb"
	"github.com/awsdocs/aws-doc-sdk-examples/gov2/demotools"
)

// IScenarioHelper defines common functions used by the workflows in this example.
type IScenarioHelper interface {
	Pause(secs int)
	GetStackOutputs(ctx context.Context, stackName string) (actions.StackOutputs, error)
	PopulateUserTable(ctx context.Context, tableName string)
	GetKnownUsers(ctx context.Context, tableName string) (actions.UserList, error)
	AddKnownUser(ctx context.Context, tableName string, user actions.User)
	ListRecentLogEvents(ctx context.Context, functionName string)
}

// ScenarioHelper contains AWS wrapper structs used by the workflows in this example.
type ScenarioHelper struct {
	questioner  demotools.IQuestioner
	dynamoActor *actions.DynamoActions
	cfnActor    *actions.CloudFormationActions
	cwlActor    *actions.CloudWatchLogsActions
	isTestRun   bool
}

// NewScenarioHelper constructs a new scenario helper.
func NewScenarioHelper(sdkConfig aws.Config, questioner demotools.IQuestioner) ScenarioHelper {
	scenario := ScenarioHelper{
		questioner:  questioner,
		dynamoActor: &actions.DynamoActions{DynamoClient: dynamodb.NewFromConfig(sdkConfig)},
		cfnActor:    &actions.CloudFormationActions{CfnClient: cloudformation.NewFromConfig(sdkConfig)},
		cwlActor:    &actions.CloudWatchLogsActions{CwlClient: cloudwatchlogs.NewFromConfig(sdkConfig)},
	}
	return scenario
}

// Pause waits for the specified number of seconds.
func (helper ScenarioHelper) Pause(secs int) {
	if !helper.isTestRun {
		time.Sleep(time.Duration(secs) * time.Second)
	}
}

// GetStackOutputs gets the outputs from the specified CloudFormation stack in a structured format.
func (helper ScenarioHelper) GetStackOutputs(ctx context.Context, stackName string) (actions.StackOutputs, error) {
	return helper.cfnActor.GetOutputs(ctx, stackName), nil
}

// PopulateUserTable fills the known user table with example data.
func (helper ScenarioHelper) PopulateUserTable(ctx context.Context, tableName string) {
	log.Printf("First, let's add some users to the DynamoDB %v table we'll use for this example.\n", tableName)
	err := helper.dynamoActor.PopulateTable(ctx, tableName)
	if err != nil {
		panic(err)
	}
}

// GetKnownUsers gets the users from the known users table in a structured format.
func (helper ScenarioHelper) GetKnownUsers(ctx context.Context, tableName string) (actions.UserList, error) {
	knownUsers, err := helper.dynamoActor.Scan(ctx, tableName)
	if err != nil {
		log.Printf("Couldn't get known users from table %v. Here's why: %v\n", tableName, err)
	}
	return knownUsers, err
}

// AddKnownUser adds a user to the known users table.
func (helper ScenarioHelper) AddKnownUser(ctx context.Context, tableName string, user actions.User) {
	log.Printf("Adding user '%v' with email '%v' to the DynamoDB known users table...\n",
		user.UserName, user.UserEmail)
	err := helper.dynamoActor.AddUser(ctx, tableName, user)
	if err != nil {
		panic(err)
	}
}

// ListRecentLogEvents gets the most recent log stream and events for the specified Lambda function and displays them.
func (helper ScenarioHelper) ListRecentLogEvents(ctx context.Context, functionName string) {
	log.Println("Waiting a few seconds to let Lambda write to CloudWatch Logs...")
	helper.Pause(10)
	log.Println("Okay, let's check the logs to find what's happened recently with your Lambda function.")
	logStream, err := helper.cwlActor.GetLatestLogStream(ctx, functionName)
	if err != nil {
		panic(err)
	}
	log.Printf("Getting some recent events from log stream %v\n", *logStream.LogStreamName)
	events, err := helper.cwlActor.GetLogEvents(ctx, functionName, *logStream.LogStreamName, 10)
	if err != nil {
		panic(err)
	}
	for _, event := range events {
		log.Printf("\t%v", *event.Message)
	}
	log.Println(strings.Repeat("-", 88))
}
```
Erstellen Sie eine Struktur, die Amazon Cognito-Aktionen umschließt.  

```
import (
	"context"
	"errors"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider/types"
)

type CognitoActions struct {
	CognitoClient *cognitoidentityprovider.Client
}



// Trigger and TriggerInfo define typed data for updating an Amazon Cognito trigger.
type Trigger int

const (
	PreSignUp Trigger = iota
	UserMigration
	PostAuthentication
)

type TriggerInfo struct {
	Trigger    Trigger
	HandlerArn *string
}

// UpdateTriggers adds or removes Lambda triggers for a user pool. When a trigger is specified with a `nil` value,
// it is removed from the user pool.
func (actor CognitoActions) UpdateTriggers(ctx context.Context, userPoolId string, triggers ...TriggerInfo) error {
	output, err := actor.CognitoClient.DescribeUserPool(ctx, &cognitoidentityprovider.DescribeUserPoolInput{
		UserPoolId: aws.String(userPoolId),
	})
	if err != nil {
		log.Printf("Couldn't get info about user pool %v. Here's why: %v\n", userPoolId, err)
		return err
	}
	lambdaConfig := output.UserPool.LambdaConfig
	for _, trigger := range triggers {
		switch trigger.Trigger {
		case PreSignUp:
			lambdaConfig.PreSignUp = trigger.HandlerArn
		case UserMigration:
			lambdaConfig.UserMigration = trigger.HandlerArn
		case PostAuthentication:
			lambdaConfig.PostAuthentication = trigger.HandlerArn
		}
	}
	_, err = actor.CognitoClient.UpdateUserPool(ctx, &cognitoidentityprovider.UpdateUserPoolInput{
		UserPoolId:   aws.String(userPoolId),
		LambdaConfig: lambdaConfig,
	})
	if err != nil {
		log.Printf("Couldn't update user pool %v. Here's why: %v\n", userPoolId, err)
	}
	return err
}



// SignUp signs up a user with Amazon Cognito.
func (actor CognitoActions) SignUp(ctx context.Context, clientId string, userName string, password string, userEmail string) (bool, error) {
	confirmed := false
	output, err := actor.CognitoClient.SignUp(ctx, &cognitoidentityprovider.SignUpInput{
		ClientId: aws.String(clientId),
		Password: aws.String(password),
		Username: aws.String(userName),
		UserAttributes: []types.AttributeType{
			{Name: aws.String("email"), Value: aws.String(userEmail)},
		},
	})
	if err != nil {
		var invalidPassword *types.InvalidPasswordException
		if errors.As(err, &invalidPassword) {
			log.Println(*invalidPassword.Message)
		} else {
			log.Printf("Couldn't sign up user %v. Here's why: %v\n", userName, err)
		}
	} else {
		confirmed = output.UserConfirmed
	}
	return confirmed, err
}



// SignIn signs in a user to Amazon Cognito using a username and password authentication flow.
func (actor CognitoActions) SignIn(ctx context.Context, clientId string, userName string, password string) (*types.AuthenticationResultType, error) {
	var authResult *types.AuthenticationResultType
	output, err := actor.CognitoClient.InitiateAuth(ctx, &cognitoidentityprovider.InitiateAuthInput{
		AuthFlow:       "USER_PASSWORD_AUTH",
		ClientId:       aws.String(clientId),
		AuthParameters: map[string]string{"USERNAME": userName, "PASSWORD": password},
	})
	if err != nil {
		var resetRequired *types.PasswordResetRequiredException
		if errors.As(err, &resetRequired) {
			log.Println(*resetRequired.Message)
		} else {
			log.Printf("Couldn't sign in user %v. Here's why: %v\n", userName, err)
		}
	} else {
		authResult = output.AuthenticationResult
	}
	return authResult, err
}



// ForgotPassword starts a password recovery flow for a user. This flow typically sends a confirmation code
// to the user's configured notification destination, such as email.
func (actor CognitoActions) ForgotPassword(ctx context.Context, clientId string, userName string) (*types.CodeDeliveryDetailsType, error) {
	output, err := actor.CognitoClient.ForgotPassword(ctx, &cognitoidentityprovider.ForgotPasswordInput{
		ClientId: aws.String(clientId),
		Username: aws.String(userName),
	})
	if err != nil {
		log.Printf("Couldn't start password reset for user '%v'. Here;s why: %v\n", userName, err)
	}
	return output.CodeDeliveryDetails, err
}



// ConfirmForgotPassword confirms a user with a confirmation code and a new password.
func (actor CognitoActions) ConfirmForgotPassword(ctx context.Context, clientId string, code string, userName string, password string) error {
	_, err := actor.CognitoClient.ConfirmForgotPassword(ctx, &cognitoidentityprovider.ConfirmForgotPasswordInput{
		ClientId:         aws.String(clientId),
		ConfirmationCode: aws.String(code),
		Password:         aws.String(password),
		Username:         aws.String(userName),
	})
	if err != nil {
		var invalidPassword *types.InvalidPasswordException
		if errors.As(err, &invalidPassword) {
			log.Println(*invalidPassword.Message)
		} else {
			log.Printf("Couldn't confirm user %v. Here's why: %v", userName, err)
		}
	}
	return err
}



// DeleteUser removes a user from the user pool.
func (actor CognitoActions) DeleteUser(ctx context.Context, userAccessToken string) error {
	_, err := actor.CognitoClient.DeleteUser(ctx, &cognitoidentityprovider.DeleteUserInput{
		AccessToken: aws.String(userAccessToken),
	})
	if err != nil {
		log.Printf("Couldn't delete user. Here's why: %v\n", err)
	}
	return err
}



// AdminCreateUser uses administrator credentials to add a user to a user pool. This method leaves the user
// in a state that requires they enter a new password next time they sign in.
func (actor CognitoActions) AdminCreateUser(ctx context.Context, userPoolId string, userName string, userEmail string) error {
	_, err := actor.CognitoClient.AdminCreateUser(ctx, &cognitoidentityprovider.AdminCreateUserInput{
		UserPoolId:     aws.String(userPoolId),
		Username:       aws.String(userName),
		MessageAction:  types.MessageActionTypeSuppress,
		UserAttributes: []types.AttributeType{{Name: aws.String("email"), Value: aws.String(userEmail)}},
	})
	if err != nil {
		var userExists *types.UsernameExistsException
		if errors.As(err, &userExists) {
			log.Printf("User %v already exists in the user pool.", userName)
			err = nil
		} else {
			log.Printf("Couldn't create user %v. Here's why: %v\n", userName, err)
		}
	}
	return err
}



// AdminSetUserPassword uses administrator credentials to set a password for a user without requiring a
// temporary password.
func (actor CognitoActions) AdminSetUserPassword(ctx context.Context, userPoolId string, userName string, password string) error {
	_, err := actor.CognitoClient.AdminSetUserPassword(ctx, &cognitoidentityprovider.AdminSetUserPasswordInput{
		Password:   aws.String(password),
		UserPoolId: aws.String(userPoolId),
		Username:   aws.String(userName),
		Permanent:  true,
	})
	if err != nil {
		var invalidPassword *types.InvalidPasswordException
		if errors.As(err, &invalidPassword) {
			log.Println(*invalidPassword.Message)
		} else {
			log.Printf("Couldn't set password for user %v. Here's why: %v\n", userName, err)
		}
	}
	return err
}
```
Erstellen Sie eine Struktur, die DynamoDB-Aktionen umhüllt.  

```
import (
	"context"
	"fmt"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/feature/dynamodb/attributevalue"
	"github.com/aws/aws-sdk-go-v2/service/dynamodb"
	"github.com/aws/aws-sdk-go-v2/service/dynamodb/types"
)

// DynamoActions encapsulates the Amazon Simple Notification Service (Amazon SNS) actions
// used in the examples.
type DynamoActions struct {
	DynamoClient *dynamodb.Client
}

// User defines structured user data.
type User struct {
	UserName  string
	UserEmail string
	LastLogin *LoginInfo `dynamodbav:",omitempty"`
}

// LoginInfo defines structured custom login data.
type LoginInfo struct {
	UserPoolId string
	ClientId   string
	Time       string
}

// UserList defines a list of users.
type UserList struct {
	Users []User
}

// UserNameList returns the usernames contained in a UserList as a list of strings.
func (users *UserList) UserNameList() []string {
	names := make([]string, len(users.Users))
	for i := 0; i < len(users.Users); i++ {
		names[i] = users.Users[i].UserName
	}
	return names
}

// PopulateTable adds a set of test users to the table.
func (actor DynamoActions) PopulateTable(ctx context.Context, tableName string) error {
	var err error
	var item map[string]types.AttributeValue
	var writeReqs []types.WriteRequest
	for i := 1; i < 4; i++ {
		item, err = attributevalue.MarshalMap(User{UserName: fmt.Sprintf("test_user_%v", i), UserEmail: fmt.Sprintf("test_email_%v@example.com", i)})
		if err != nil {
			log.Printf("Couldn't marshall user into DynamoDB format. Here's why: %v\n", err)
			return err
		}
		writeReqs = append(writeReqs, types.WriteRequest{PutRequest: &types.PutRequest{Item: item}})
	}
	_, err = actor.DynamoClient.BatchWriteItem(ctx, &dynamodb.BatchWriteItemInput{
		RequestItems: map[string][]types.WriteRequest{tableName: writeReqs},
	})
	if err != nil {
		log.Printf("Couldn't populate table %v with users. Here's why: %v\n", tableName, err)
	}
	return err
}

// Scan scans the table for all items.
func (actor DynamoActions) Scan(ctx context.Context, tableName string) (UserList, error) {
	var userList UserList
	output, err := actor.DynamoClient.Scan(ctx, &dynamodb.ScanInput{
		TableName: aws.String(tableName),
	})
	if err != nil {
		log.Printf("Couldn't scan table %v for items. Here's why: %v\n", tableName, err)
	} else {
		err = attributevalue.UnmarshalListOfMaps(output.Items, &userList.Users)
		if err != nil {
			log.Printf("Couldn't unmarshal items into users. Here's why: %v\n", err)
		}
	}
	return userList, err
}

// AddUser adds a user item to a table.
func (actor DynamoActions) AddUser(ctx context.Context, tableName string, user User) error {
	userItem, err := attributevalue.MarshalMap(user)
	if err != nil {
		log.Printf("Couldn't marshall user to item. Here's why: %v\n", err)
	}
	_, err = actor.DynamoClient.PutItem(ctx, &dynamodb.PutItemInput{
		Item:      userItem,
		TableName: aws.String(tableName),
	})
	if err != nil {
		log.Printf("Couldn't put item in table %v. Here's why: %v", tableName, err)
	}
	return err
}
```
Erstellen Sie eine Struktur, die CloudWatch Logs-Aktionen umschließt.  

```
import (
	"context"
	"fmt"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cloudwatchlogs"
	"github.com/aws/aws-sdk-go-v2/service/cloudwatchlogs/types"
)

type CloudWatchLogsActions struct {
	CwlClient *cloudwatchlogs.Client
}

// GetLatestLogStream gets the most recent log stream for a Lambda function.
func (actor CloudWatchLogsActions) GetLatestLogStream(ctx context.Context, functionName string) (types.LogStream, error) {
	var logStream types.LogStream
	logGroupName := fmt.Sprintf("/aws/lambda/%s", functionName)
	output, err := actor.CwlClient.DescribeLogStreams(ctx, &cloudwatchlogs.DescribeLogStreamsInput{
		Descending:   aws.Bool(true),
		Limit:        aws.Int32(1),
		LogGroupName: aws.String(logGroupName),
		OrderBy:      types.OrderByLastEventTime,
	})
	if err != nil {
		log.Printf("Couldn't get log streams for log group %v. Here's why: %v\n", logGroupName, err)
	} else {
		logStream = output.LogStreams[0]
	}
	return logStream, err
}

// GetLogEvents gets the most recent eventCount events from the specified log stream.
func (actor CloudWatchLogsActions) GetLogEvents(ctx context.Context, functionName string, logStreamName string, eventCount int32) (
	[]types.OutputLogEvent, error) {
	var events []types.OutputLogEvent
	logGroupName := fmt.Sprintf("/aws/lambda/%s", functionName)
	output, err := actor.CwlClient.GetLogEvents(ctx, &cloudwatchlogs.GetLogEventsInput{
		LogStreamName: aws.String(logStreamName),
		Limit:         aws.Int32(eventCount),
		LogGroupName:  aws.String(logGroupName),
	})
	if err != nil {
		log.Printf("Couldn't get log event for log stream %v. Here's why: %v\n", logStreamName, err)
	} else {
		events = output.Events
	}
	return events, err
}
```
Erstellen Sie eine Struktur, die Aktionen umschließt. CloudFormation   

```
import (
	"context"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cloudformation"
)

// StackOutputs defines a map of outputs from a specific stack.
type StackOutputs map[string]string

type CloudFormationActions struct {
	CfnClient *cloudformation.Client
}

// GetOutputs gets the outputs from a CloudFormation stack and puts them into a structured format.
func (actor CloudFormationActions) GetOutputs(ctx context.Context, stackName string) StackOutputs {
	output, err := actor.CfnClient.DescribeStacks(ctx, &cloudformation.DescribeStacksInput{
		StackName: aws.String(stackName),
	})
	if err != nil || len(output.Stacks) == 0 {
		log.Panicf("Couldn't find a CloudFormation stack named %v. Here's why: %v\n", stackName, err)
	}
	stackOutputs := StackOutputs{}
	for _, out := range output.Stacks[0].Outputs {
		stackOutputs[*out.OutputKey] = *out.OutputValue
	}
	return stackOutputs
}
```
Bereinigen von Ressourcen.  

```
import (
	"context"
	"log"
	"user_pools_and_lambda_triggers/actions"

	"github.com/awsdocs/aws-doc-sdk-examples/gov2/demotools"
)

// Resources keeps track of AWS resources created during an example and handles
// cleanup when the example finishes.
type Resources struct {
	userPoolId       string
	userAccessTokens []string
	triggers         []actions.Trigger

	cognitoActor *actions.CognitoActions
	questioner   demotools.IQuestioner
}

func (resources *Resources) init(cognitoActor *actions.CognitoActions, questioner demotools.IQuestioner) {
	resources.userAccessTokens = []string{}
	resources.triggers = []actions.Trigger{}
	resources.cognitoActor = cognitoActor
	resources.questioner = questioner
}

// Cleanup deletes all AWS resources created during an example.
func (resources *Resources) Cleanup(ctx context.Context) {
	defer func() {
		if r := recover(); r != nil {
			log.Printf("Something went wrong during cleanup.\n%v\n", r)
			log.Println("Use the AWS Management Console to remove any remaining resources \n" +
				"that were created for this scenario.")
		}
	}()

	wantDelete := resources.questioner.AskBool("Do you want to remove all of the AWS resources that were created "+
		"during this demo (y/n)?", "y")
	if wantDelete {
		for _, accessToken := range resources.userAccessTokens {
			err := resources.cognitoActor.DeleteUser(ctx, accessToken)
			if err != nil {
				log.Println("Couldn't delete user during cleanup.")
				panic(err)
			}
			log.Println("Deleted user.")
		}
		triggerList := make([]actions.TriggerInfo, len(resources.triggers))
		for i := 0; i < len(resources.triggers); i++ {
			triggerList[i] = actions.TriggerInfo{Trigger: resources.triggers[i], HandlerArn: nil}
		}
		err := resources.cognitoActor.UpdateTriggers(ctx, resources.userPoolId, triggerList...)
		if err != nil {
			log.Println("Couldn't update Cognito triggers during cleanup.")
			panic(err)
		}
		log.Println("Removed Cognito triggers from user pool.")
	} else {
		log.Println("Be sure to remove resources when you're done with them to avoid unexpected charges!")
	}
}
```
+ Weitere API-Informationen finden Sie in den folgenden Themen der *AWS SDK für Go -API-Referenz*.
  + [ConfirmForgotPassword](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.ConfirmForgotPassword)
  + [DeleteUser](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.DeleteUser)
  + [ForgotPassword](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.ForgotPassword)
  + [InitiateAuth](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.InitiateAuth)
  + [SignUp](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.SignUp)
  + [UpdateUserPool](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.UpdateUserPool)

### Schreiben von benutzerdefinierten Aktivitätsdaten mit einer Lambda-Funktion nach der Amazon Cognito-Benutzerauthentifizierung
<a name="cross_CognitoCustomActivityLog_go_2_topic"></a>

Das folgende Codebeispiel veranschaulicht, wie benutzerdefinierte Aktivitätsdaten mit einer Lambda-Funktion nach der Amazon-Cognito-Benutzerauthentifizierung geschrieben werden.
+ Verwenden Sie Administratorfunktionen, um einen Benutzer zu einem Benutzerpool hinzuzufügen.
+ Konfigurieren Sie einen Benutzerpool, um eine Lambda-Funktion für den `PostAuthentication`-Trigger aufzurufen.
+ Melden Sie den neuen Benutzer bei Amazon Cognito an.
+ Die Lambda-Funktion schreibt benutzerdefinierte Informationen in CloudWatch Logs und in eine DynamoDB-Tabelle.
+ Ermitteln Sie benutzerdefinierte Daten aus der DynamoDB-Tabelle, zeigen Sie diese an und bereinigen Sie dann die Ressourcen.

**SDK für Go V2**  
 Es gibt noch mehr dazu. GitHub Hier finden Sie das vollständige Beispiel und erfahren, wie Sie das [AWS -Code-Beispiel-](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/gov2/workflows/user_pools_and_lambda_triggers#code-examples) einrichten und ausführen. 
Führen Sie ein interaktives Szenario an einem Prompt aus.  

```
import (
	"context"
	"errors"
	"log"
	"strings"
	"user_pools_and_lambda_triggers/actions"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider/types"
	"github.com/awsdocs/aws-doc-sdk-examples/gov2/demotools"
)

// ActivityLog separates the steps of this scenario into individual functions so that
// they are simpler to read and understand.
type ActivityLog struct {
	helper       IScenarioHelper
	questioner   demotools.IQuestioner
	resources    Resources
	cognitoActor *actions.CognitoActions
}

// NewActivityLog constructs a new activity log runner.
func NewActivityLog(sdkConfig aws.Config, questioner demotools.IQuestioner, helper IScenarioHelper) ActivityLog {
	scenario := ActivityLog{
		helper:       helper,
		questioner:   questioner,
		resources:    Resources{},
		cognitoActor: &actions.CognitoActions{CognitoClient: cognitoidentityprovider.NewFromConfig(sdkConfig)},
	}
	scenario.resources.init(scenario.cognitoActor, questioner)
	return scenario
}

// AddUserToPool selects a user from the known users table and uses administrator credentials to add the user to the user pool.
func (runner *ActivityLog) AddUserToPool(ctx context.Context, userPoolId string, tableName string) (string, string) {
	log.Println("To facilitate this example, let's add a user to the user pool using administrator privileges.")
	users, err := runner.helper.GetKnownUsers(ctx, tableName)
	if err != nil {
		panic(err)
	}
	user := users.Users[0]
	log.Printf("Adding known user %v to the user pool.\n", user.UserName)
	err = runner.cognitoActor.AdminCreateUser(ctx, userPoolId, user.UserName, user.UserEmail)
	if err != nil {
		panic(err)
	}
	pwSet := false
	password := runner.questioner.AskPassword("\nEnter a password that has at least eight characters, uppercase, lowercase, numbers and symbols.\n"+
		"(the password will not display as you type):", 8)
	for !pwSet {
		log.Printf("\nSetting password for user '%v'.\n", user.UserName)
		err = runner.cognitoActor.AdminSetUserPassword(ctx, userPoolId, user.UserName, password)
		if err != nil {
			var invalidPassword *types.InvalidPasswordException
			if errors.As(err, &invalidPassword) {
				password = runner.questioner.AskPassword("\nEnter another password:", 8)
			} else {
				panic(err)
			}
		} else {
			pwSet = true
		}
	}

	log.Println(strings.Repeat("-", 88))

	return user.UserName, password
}

// AddActivityLogTrigger adds a Lambda handler as an invocation target for the PostAuthentication trigger.
func (runner *ActivityLog) AddActivityLogTrigger(ctx context.Context, userPoolId string, activityLogArn string) {
	log.Println("Let's add a Lambda function to handle the PostAuthentication trigger from Cognito.\n" +
		"This trigger happens after a user is authenticated, and lets your function take action, such as logging\n" +
		"the outcome.")
	err := runner.cognitoActor.UpdateTriggers(
		ctx, userPoolId,
		actions.TriggerInfo{Trigger: actions.PostAuthentication, HandlerArn: aws.String(activityLogArn)})
	if err != nil {
		panic(err)
	}
	runner.resources.triggers = append(runner.resources.triggers, actions.PostAuthentication)
	log.Printf("Lambda function %v added to user pool %v to handle PostAuthentication Cognito trigger.\n",
		activityLogArn, userPoolId)

	log.Println(strings.Repeat("-", 88))
}

// SignInUser signs in as the specified user.
func (runner *ActivityLog) SignInUser(ctx context.Context, clientId string, userName string, password string) {
	log.Printf("Now we'll sign in user %v and check the results in the logs and the DynamoDB table.", userName)
	runner.questioner.Ask("Press Enter when you're ready.")
	authResult, err := runner.cognitoActor.SignIn(ctx, clientId, userName, password)
	if err != nil {
		panic(err)
	}
	log.Println("Sign in successful.",
		"The PostAuthentication Lambda handler writes custom information to CloudWatch Logs.")

	runner.resources.userAccessTokens = append(runner.resources.userAccessTokens, *authResult.AccessToken)
}

// GetKnownUserLastLogin gets the login info for a user from the Amazon DynamoDB table and displays it.
func (runner *ActivityLog) GetKnownUserLastLogin(ctx context.Context, tableName string, userName string) {
	log.Println("The PostAuthentication handler also writes login data to the DynamoDB table.")
	runner.questioner.Ask("Press Enter when you're ready to continue.")
	users, err := runner.helper.GetKnownUsers(ctx, tableName)
	if err != nil {
		panic(err)
	}
	for _, user := range users.Users {
		if user.UserName == userName {
			log.Println("The last login info for the user in the known users table is:")
			log.Printf("\t%+v", *user.LastLogin)
		}
	}
	log.Println(strings.Repeat("-", 88))
}

// Run runs the scenario.
func (runner *ActivityLog) Run(ctx context.Context, stackName string) {
	defer func() {
		if r := recover(); r != nil {
			log.Println("Something went wrong with the demo.")
			runner.resources.Cleanup(ctx)
		}
	}()

	log.Println(strings.Repeat("-", 88))
	log.Printf("Welcome\n")

	log.Println(strings.Repeat("-", 88))

	stackOutputs, err := runner.helper.GetStackOutputs(ctx, stackName)
	if err != nil {
		panic(err)
	}
	runner.resources.userPoolId = stackOutputs["UserPoolId"]
	runner.helper.PopulateUserTable(ctx, stackOutputs["TableName"])
	userName, password := runner.AddUserToPool(ctx, stackOutputs["UserPoolId"], stackOutputs["TableName"])

	runner.AddActivityLogTrigger(ctx, stackOutputs["UserPoolId"], stackOutputs["ActivityLogFunctionArn"])
	runner.SignInUser(ctx, stackOutputs["UserPoolClientId"], userName, password)
	runner.helper.ListRecentLogEvents(ctx, stackOutputs["ActivityLogFunction"])
	runner.GetKnownUserLastLogin(ctx, stackOutputs["TableName"], userName)

	runner.resources.Cleanup(ctx)

	log.Println(strings.Repeat("-", 88))
	log.Println("Thanks for watching!")
	log.Println(strings.Repeat("-", 88))
}
```
Behandeln Sie den `PostAuthentication`-Trigger mit einer Lambda-Funktion.  

```
import (
	"context"
	"fmt"
	"log"
	"os"
	"time"

	"github.com/aws/aws-lambda-go/events"
	"github.com/aws/aws-lambda-go/lambda"
	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/config"
	"github.com/aws/aws-sdk-go-v2/feature/dynamodb/attributevalue"
	"github.com/aws/aws-sdk-go-v2/service/dynamodb"
	dynamodbtypes "github.com/aws/aws-sdk-go-v2/service/dynamodb/types"
)

const TABLE_NAME = "TABLE_NAME"

// LoginInfo defines structured login data that can be marshalled to a DynamoDB format.
type LoginInfo struct {
	UserPoolId string `dynamodbav:"UserPoolId"`
	ClientId   string `dynamodbav:"ClientId"`
	Time       string `dynamodbav:"Time"`
}

// UserInfo defines structured user data that can be marshalled to a DynamoDB format.
type UserInfo struct {
	UserName  string    `dynamodbav:"UserName"`
	UserEmail string    `dynamodbav:"UserEmail"`
	LastLogin LoginInfo `dynamodbav:"LastLogin"`
}

// GetKey marshals the user email value to a DynamoDB key format.
func (user UserInfo) GetKey() map[string]dynamodbtypes.AttributeValue {
	userEmail, err := attributevalue.Marshal(user.UserEmail)
	if err != nil {
		panic(err)
	}
	return map[string]dynamodbtypes.AttributeValue{"UserEmail": userEmail}
}

type handler struct {
	dynamoClient *dynamodb.Client
}

// HandleRequest handles the PostAuthentication event by writing custom data to the logs and
// to an Amazon DynamoDB table.
func (h *handler) HandleRequest(ctx context.Context, event events.CognitoEventUserPoolsPostAuthentication) (events.CognitoEventUserPoolsPostAuthentication, error) {
	log.Printf("Received post authentication trigger from %v for user '%v'", event.TriggerSource, event.UserName)
	tableName := os.Getenv(TABLE_NAME)
	user := UserInfo{
		UserName:  event.UserName,
		UserEmail: event.Request.UserAttributes["email"],
		LastLogin: LoginInfo{
			UserPoolId: event.UserPoolID,
			ClientId:   event.CallerContext.ClientID,
			Time:       time.Now().Format(time.UnixDate),
		},
	}
	// Write to CloudWatch Logs.
	fmt.Printf("%#v", user)

	// Also write to an external system. This examples uses DynamoDB to demonstrate.
	userMap, err := attributevalue.MarshalMap(user)
	if err != nil {
		log.Printf("Couldn't marshal to DynamoDB map. Here's why: %v\n", err)
	} else if len(userMap) == 0 {
		log.Printf("User info marshaled to an empty map.")
	} else {
		_, err := h.dynamoClient.PutItem(ctx, &dynamodb.PutItemInput{
			Item:      userMap,
			TableName: aws.String(tableName),
		})
		if err != nil {
			log.Printf("Couldn't write to DynamoDB. Here's why: %v\n", err)
		} else {
			log.Printf("Wrote user info to DynamoDB table %v.\n", tableName)
		}
	}

	return event, nil
}

func main() {
	ctx := context.Background()
	sdkConfig, err := config.LoadDefaultConfig(ctx)
	if err != nil {
		log.Panicln(err)
	}
	h := handler{
		dynamoClient: dynamodb.NewFromConfig(sdkConfig),
	}
	lambda.Start(h.HandleRequest)
}
```
Erstellen Sie eine Struktur, die allgemeine Aufgaben ausführt.  

```
import (
	"context"
	"log"
	"strings"
	"time"
	"user_pools_and_lambda_triggers/actions"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cloudformation"
	"github.com/aws/aws-sdk-go-v2/service/cloudwatchlogs"
	"github.com/aws/aws-sdk-go-v2/service/dynamodb"
	"github.com/awsdocs/aws-doc-sdk-examples/gov2/demotools"
)

// IScenarioHelper defines common functions used by the workflows in this example.
type IScenarioHelper interface {
	Pause(secs int)
	GetStackOutputs(ctx context.Context, stackName string) (actions.StackOutputs, error)
	PopulateUserTable(ctx context.Context, tableName string)
	GetKnownUsers(ctx context.Context, tableName string) (actions.UserList, error)
	AddKnownUser(ctx context.Context, tableName string, user actions.User)
	ListRecentLogEvents(ctx context.Context, functionName string)
}

// ScenarioHelper contains AWS wrapper structs used by the workflows in this example.
type ScenarioHelper struct {
	questioner  demotools.IQuestioner
	dynamoActor *actions.DynamoActions
	cfnActor    *actions.CloudFormationActions
	cwlActor    *actions.CloudWatchLogsActions
	isTestRun   bool
}

// NewScenarioHelper constructs a new scenario helper.
func NewScenarioHelper(sdkConfig aws.Config, questioner demotools.IQuestioner) ScenarioHelper {
	scenario := ScenarioHelper{
		questioner:  questioner,
		dynamoActor: &actions.DynamoActions{DynamoClient: dynamodb.NewFromConfig(sdkConfig)},
		cfnActor:    &actions.CloudFormationActions{CfnClient: cloudformation.NewFromConfig(sdkConfig)},
		cwlActor:    &actions.CloudWatchLogsActions{CwlClient: cloudwatchlogs.NewFromConfig(sdkConfig)},
	}
	return scenario
}

// Pause waits for the specified number of seconds.
func (helper ScenarioHelper) Pause(secs int) {
	if !helper.isTestRun {
		time.Sleep(time.Duration(secs) * time.Second)
	}
}

// GetStackOutputs gets the outputs from the specified CloudFormation stack in a structured format.
func (helper ScenarioHelper) GetStackOutputs(ctx context.Context, stackName string) (actions.StackOutputs, error) {
	return helper.cfnActor.GetOutputs(ctx, stackName), nil
}

// PopulateUserTable fills the known user table with example data.
func (helper ScenarioHelper) PopulateUserTable(ctx context.Context, tableName string) {
	log.Printf("First, let's add some users to the DynamoDB %v table we'll use for this example.\n", tableName)
	err := helper.dynamoActor.PopulateTable(ctx, tableName)
	if err != nil {
		panic(err)
	}
}

// GetKnownUsers gets the users from the known users table in a structured format.
func (helper ScenarioHelper) GetKnownUsers(ctx context.Context, tableName string) (actions.UserList, error) {
	knownUsers, err := helper.dynamoActor.Scan(ctx, tableName)
	if err != nil {
		log.Printf("Couldn't get known users from table %v. Here's why: %v\n", tableName, err)
	}
	return knownUsers, err
}

// AddKnownUser adds a user to the known users table.
func (helper ScenarioHelper) AddKnownUser(ctx context.Context, tableName string, user actions.User) {
	log.Printf("Adding user '%v' with email '%v' to the DynamoDB known users table...\n",
		user.UserName, user.UserEmail)
	err := helper.dynamoActor.AddUser(ctx, tableName, user)
	if err != nil {
		panic(err)
	}
}

// ListRecentLogEvents gets the most recent log stream and events for the specified Lambda function and displays them.
func (helper ScenarioHelper) ListRecentLogEvents(ctx context.Context, functionName string) {
	log.Println("Waiting a few seconds to let Lambda write to CloudWatch Logs...")
	helper.Pause(10)
	log.Println("Okay, let's check the logs to find what's happened recently with your Lambda function.")
	logStream, err := helper.cwlActor.GetLatestLogStream(ctx, functionName)
	if err != nil {
		panic(err)
	}
	log.Printf("Getting some recent events from log stream %v\n", *logStream.LogStreamName)
	events, err := helper.cwlActor.GetLogEvents(ctx, functionName, *logStream.LogStreamName, 10)
	if err != nil {
		panic(err)
	}
	for _, event := range events {
		log.Printf("\t%v", *event.Message)
	}
	log.Println(strings.Repeat("-", 88))
}
```
Erstellen Sie eine Struktur, die Amazon Cognito-Aktionen umschließt.  

```
import (
	"context"
	"errors"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider"
	"github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider/types"
)

type CognitoActions struct {
	CognitoClient *cognitoidentityprovider.Client
}



// Trigger and TriggerInfo define typed data for updating an Amazon Cognito trigger.
type Trigger int

const (
	PreSignUp Trigger = iota
	UserMigration
	PostAuthentication
)

type TriggerInfo struct {
	Trigger    Trigger
	HandlerArn *string
}

// UpdateTriggers adds or removes Lambda triggers for a user pool. When a trigger is specified with a `nil` value,
// it is removed from the user pool.
func (actor CognitoActions) UpdateTriggers(ctx context.Context, userPoolId string, triggers ...TriggerInfo) error {
	output, err := actor.CognitoClient.DescribeUserPool(ctx, &cognitoidentityprovider.DescribeUserPoolInput{
		UserPoolId: aws.String(userPoolId),
	})
	if err != nil {
		log.Printf("Couldn't get info about user pool %v. Here's why: %v\n", userPoolId, err)
		return err
	}
	lambdaConfig := output.UserPool.LambdaConfig
	for _, trigger := range triggers {
		switch trigger.Trigger {
		case PreSignUp:
			lambdaConfig.PreSignUp = trigger.HandlerArn
		case UserMigration:
			lambdaConfig.UserMigration = trigger.HandlerArn
		case PostAuthentication:
			lambdaConfig.PostAuthentication = trigger.HandlerArn
		}
	}
	_, err = actor.CognitoClient.UpdateUserPool(ctx, &cognitoidentityprovider.UpdateUserPoolInput{
		UserPoolId:   aws.String(userPoolId),
		LambdaConfig: lambdaConfig,
	})
	if err != nil {
		log.Printf("Couldn't update user pool %v. Here's why: %v\n", userPoolId, err)
	}
	return err
}



// SignUp signs up a user with Amazon Cognito.
func (actor CognitoActions) SignUp(ctx context.Context, clientId string, userName string, password string, userEmail string) (bool, error) {
	confirmed := false
	output, err := actor.CognitoClient.SignUp(ctx, &cognitoidentityprovider.SignUpInput{
		ClientId: aws.String(clientId),
		Password: aws.String(password),
		Username: aws.String(userName),
		UserAttributes: []types.AttributeType{
			{Name: aws.String("email"), Value: aws.String(userEmail)},
		},
	})
	if err != nil {
		var invalidPassword *types.InvalidPasswordException
		if errors.As(err, &invalidPassword) {
			log.Println(*invalidPassword.Message)
		} else {
			log.Printf("Couldn't sign up user %v. Here's why: %v\n", userName, err)
		}
	} else {
		confirmed = output.UserConfirmed
	}
	return confirmed, err
}



// SignIn signs in a user to Amazon Cognito using a username and password authentication flow.
func (actor CognitoActions) SignIn(ctx context.Context, clientId string, userName string, password string) (*types.AuthenticationResultType, error) {
	var authResult *types.AuthenticationResultType
	output, err := actor.CognitoClient.InitiateAuth(ctx, &cognitoidentityprovider.InitiateAuthInput{
		AuthFlow:       "USER_PASSWORD_AUTH",
		ClientId:       aws.String(clientId),
		AuthParameters: map[string]string{"USERNAME": userName, "PASSWORD": password},
	})
	if err != nil {
		var resetRequired *types.PasswordResetRequiredException
		if errors.As(err, &resetRequired) {
			log.Println(*resetRequired.Message)
		} else {
			log.Printf("Couldn't sign in user %v. Here's why: %v\n", userName, err)
		}
	} else {
		authResult = output.AuthenticationResult
	}
	return authResult, err
}



// ForgotPassword starts a password recovery flow for a user. This flow typically sends a confirmation code
// to the user's configured notification destination, such as email.
func (actor CognitoActions) ForgotPassword(ctx context.Context, clientId string, userName string) (*types.CodeDeliveryDetailsType, error) {
	output, err := actor.CognitoClient.ForgotPassword(ctx, &cognitoidentityprovider.ForgotPasswordInput{
		ClientId: aws.String(clientId),
		Username: aws.String(userName),
	})
	if err != nil {
		log.Printf("Couldn't start password reset for user '%v'. Here;s why: %v\n", userName, err)
	}
	return output.CodeDeliveryDetails, err
}



// ConfirmForgotPassword confirms a user with a confirmation code and a new password.
func (actor CognitoActions) ConfirmForgotPassword(ctx context.Context, clientId string, code string, userName string, password string) error {
	_, err := actor.CognitoClient.ConfirmForgotPassword(ctx, &cognitoidentityprovider.ConfirmForgotPasswordInput{
		ClientId:         aws.String(clientId),
		ConfirmationCode: aws.String(code),
		Password:         aws.String(password),
		Username:         aws.String(userName),
	})
	if err != nil {
		var invalidPassword *types.InvalidPasswordException
		if errors.As(err, &invalidPassword) {
			log.Println(*invalidPassword.Message)
		} else {
			log.Printf("Couldn't confirm user %v. Here's why: %v", userName, err)
		}
	}
	return err
}



// DeleteUser removes a user from the user pool.
func (actor CognitoActions) DeleteUser(ctx context.Context, userAccessToken string) error {
	_, err := actor.CognitoClient.DeleteUser(ctx, &cognitoidentityprovider.DeleteUserInput{
		AccessToken: aws.String(userAccessToken),
	})
	if err != nil {
		log.Printf("Couldn't delete user. Here's why: %v\n", err)
	}
	return err
}



// AdminCreateUser uses administrator credentials to add a user to a user pool. This method leaves the user
// in a state that requires they enter a new password next time they sign in.
func (actor CognitoActions) AdminCreateUser(ctx context.Context, userPoolId string, userName string, userEmail string) error {
	_, err := actor.CognitoClient.AdminCreateUser(ctx, &cognitoidentityprovider.AdminCreateUserInput{
		UserPoolId:     aws.String(userPoolId),
		Username:       aws.String(userName),
		MessageAction:  types.MessageActionTypeSuppress,
		UserAttributes: []types.AttributeType{{Name: aws.String("email"), Value: aws.String(userEmail)}},
	})
	if err != nil {
		var userExists *types.UsernameExistsException
		if errors.As(err, &userExists) {
			log.Printf("User %v already exists in the user pool.", userName)
			err = nil
		} else {
			log.Printf("Couldn't create user %v. Here's why: %v\n", userName, err)
		}
	}
	return err
}



// AdminSetUserPassword uses administrator credentials to set a password for a user without requiring a
// temporary password.
func (actor CognitoActions) AdminSetUserPassword(ctx context.Context, userPoolId string, userName string, password string) error {
	_, err := actor.CognitoClient.AdminSetUserPassword(ctx, &cognitoidentityprovider.AdminSetUserPasswordInput{
		Password:   aws.String(password),
		UserPoolId: aws.String(userPoolId),
		Username:   aws.String(userName),
		Permanent:  true,
	})
	if err != nil {
		var invalidPassword *types.InvalidPasswordException
		if errors.As(err, &invalidPassword) {
			log.Println(*invalidPassword.Message)
		} else {
			log.Printf("Couldn't set password for user %v. Here's why: %v\n", userName, err)
		}
	}
	return err
}
```
Erstellen Sie eine Struktur, die DynamoDB-Aktionen umhüllt.  

```
import (
	"context"
	"fmt"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/feature/dynamodb/attributevalue"
	"github.com/aws/aws-sdk-go-v2/service/dynamodb"
	"github.com/aws/aws-sdk-go-v2/service/dynamodb/types"
)

// DynamoActions encapsulates the Amazon Simple Notification Service (Amazon SNS) actions
// used in the examples.
type DynamoActions struct {
	DynamoClient *dynamodb.Client
}

// User defines structured user data.
type User struct {
	UserName  string
	UserEmail string
	LastLogin *LoginInfo `dynamodbav:",omitempty"`
}

// LoginInfo defines structured custom login data.
type LoginInfo struct {
	UserPoolId string
	ClientId   string
	Time       string
}

// UserList defines a list of users.
type UserList struct {
	Users []User
}

// UserNameList returns the usernames contained in a UserList as a list of strings.
func (users *UserList) UserNameList() []string {
	names := make([]string, len(users.Users))
	for i := 0; i < len(users.Users); i++ {
		names[i] = users.Users[i].UserName
	}
	return names
}

// PopulateTable adds a set of test users to the table.
func (actor DynamoActions) PopulateTable(ctx context.Context, tableName string) error {
	var err error
	var item map[string]types.AttributeValue
	var writeReqs []types.WriteRequest
	for i := 1; i < 4; i++ {
		item, err = attributevalue.MarshalMap(User{UserName: fmt.Sprintf("test_user_%v", i), UserEmail: fmt.Sprintf("test_email_%v@example.com", i)})
		if err != nil {
			log.Printf("Couldn't marshall user into DynamoDB format. Here's why: %v\n", err)
			return err
		}
		writeReqs = append(writeReqs, types.WriteRequest{PutRequest: &types.PutRequest{Item: item}})
	}
	_, err = actor.DynamoClient.BatchWriteItem(ctx, &dynamodb.BatchWriteItemInput{
		RequestItems: map[string][]types.WriteRequest{tableName: writeReqs},
	})
	if err != nil {
		log.Printf("Couldn't populate table %v with users. Here's why: %v\n", tableName, err)
	}
	return err
}

// Scan scans the table for all items.
func (actor DynamoActions) Scan(ctx context.Context, tableName string) (UserList, error) {
	var userList UserList
	output, err := actor.DynamoClient.Scan(ctx, &dynamodb.ScanInput{
		TableName: aws.String(tableName),
	})
	if err != nil {
		log.Printf("Couldn't scan table %v for items. Here's why: %v\n", tableName, err)
	} else {
		err = attributevalue.UnmarshalListOfMaps(output.Items, &userList.Users)
		if err != nil {
			log.Printf("Couldn't unmarshal items into users. Here's why: %v\n", err)
		}
	}
	return userList, err
}

// AddUser adds a user item to a table.
func (actor DynamoActions) AddUser(ctx context.Context, tableName string, user User) error {
	userItem, err := attributevalue.MarshalMap(user)
	if err != nil {
		log.Printf("Couldn't marshall user to item. Here's why: %v\n", err)
	}
	_, err = actor.DynamoClient.PutItem(ctx, &dynamodb.PutItemInput{
		Item:      userItem,
		TableName: aws.String(tableName),
	})
	if err != nil {
		log.Printf("Couldn't put item in table %v. Here's why: %v", tableName, err)
	}
	return err
}
```
Erstellen Sie eine Struktur, die CloudWatch Logs-Aktionen umschließt.  

```
import (
	"context"
	"fmt"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cloudwatchlogs"
	"github.com/aws/aws-sdk-go-v2/service/cloudwatchlogs/types"
)

type CloudWatchLogsActions struct {
	CwlClient *cloudwatchlogs.Client
}

// GetLatestLogStream gets the most recent log stream for a Lambda function.
func (actor CloudWatchLogsActions) GetLatestLogStream(ctx context.Context, functionName string) (types.LogStream, error) {
	var logStream types.LogStream
	logGroupName := fmt.Sprintf("/aws/lambda/%s", functionName)
	output, err := actor.CwlClient.DescribeLogStreams(ctx, &cloudwatchlogs.DescribeLogStreamsInput{
		Descending:   aws.Bool(true),
		Limit:        aws.Int32(1),
		LogGroupName: aws.String(logGroupName),
		OrderBy:      types.OrderByLastEventTime,
	})
	if err != nil {
		log.Printf("Couldn't get log streams for log group %v. Here's why: %v\n", logGroupName, err)
	} else {
		logStream = output.LogStreams[0]
	}
	return logStream, err
}

// GetLogEvents gets the most recent eventCount events from the specified log stream.
func (actor CloudWatchLogsActions) GetLogEvents(ctx context.Context, functionName string, logStreamName string, eventCount int32) (
	[]types.OutputLogEvent, error) {
	var events []types.OutputLogEvent
	logGroupName := fmt.Sprintf("/aws/lambda/%s", functionName)
	output, err := actor.CwlClient.GetLogEvents(ctx, &cloudwatchlogs.GetLogEventsInput{
		LogStreamName: aws.String(logStreamName),
		Limit:         aws.Int32(eventCount),
		LogGroupName:  aws.String(logGroupName),
	})
	if err != nil {
		log.Printf("Couldn't get log event for log stream %v. Here's why: %v\n", logStreamName, err)
	} else {
		events = output.Events
	}
	return events, err
}
```
Erstellen Sie eine Struktur, die Aktionen umschließt. CloudFormation   

```
import (
	"context"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/cloudformation"
)

// StackOutputs defines a map of outputs from a specific stack.
type StackOutputs map[string]string

type CloudFormationActions struct {
	CfnClient *cloudformation.Client
}

// GetOutputs gets the outputs from a CloudFormation stack and puts them into a structured format.
func (actor CloudFormationActions) GetOutputs(ctx context.Context, stackName string) StackOutputs {
	output, err := actor.CfnClient.DescribeStacks(ctx, &cloudformation.DescribeStacksInput{
		StackName: aws.String(stackName),
	})
	if err != nil || len(output.Stacks) == 0 {
		log.Panicf("Couldn't find a CloudFormation stack named %v. Here's why: %v\n", stackName, err)
	}
	stackOutputs := StackOutputs{}
	for _, out := range output.Stacks[0].Outputs {
		stackOutputs[*out.OutputKey] = *out.OutputValue
	}
	return stackOutputs
}
```
Bereinigen von Ressourcen.  

```
import (
	"context"
	"log"
	"user_pools_and_lambda_triggers/actions"

	"github.com/awsdocs/aws-doc-sdk-examples/gov2/demotools"
)

// Resources keeps track of AWS resources created during an example and handles
// cleanup when the example finishes.
type Resources struct {
	userPoolId       string
	userAccessTokens []string
	triggers         []actions.Trigger

	cognitoActor *actions.CognitoActions
	questioner   demotools.IQuestioner
}

func (resources *Resources) init(cognitoActor *actions.CognitoActions, questioner demotools.IQuestioner) {
	resources.userAccessTokens = []string{}
	resources.triggers = []actions.Trigger{}
	resources.cognitoActor = cognitoActor
	resources.questioner = questioner
}

// Cleanup deletes all AWS resources created during an example.
func (resources *Resources) Cleanup(ctx context.Context) {
	defer func() {
		if r := recover(); r != nil {
			log.Printf("Something went wrong during cleanup.\n%v\n", r)
			log.Println("Use the AWS Management Console to remove any remaining resources \n" +
				"that were created for this scenario.")
		}
	}()

	wantDelete := resources.questioner.AskBool("Do you want to remove all of the AWS resources that were created "+
		"during this demo (y/n)?", "y")
	if wantDelete {
		for _, accessToken := range resources.userAccessTokens {
			err := resources.cognitoActor.DeleteUser(ctx, accessToken)
			if err != nil {
				log.Println("Couldn't delete user during cleanup.")
				panic(err)
			}
			log.Println("Deleted user.")
		}
		triggerList := make([]actions.TriggerInfo, len(resources.triggers))
		for i := 0; i < len(resources.triggers); i++ {
			triggerList[i] = actions.TriggerInfo{Trigger: resources.triggers[i], HandlerArn: nil}
		}
		err := resources.cognitoActor.UpdateTriggers(ctx, resources.userPoolId, triggerList...)
		if err != nil {
			log.Println("Couldn't update Cognito triggers during cleanup.")
			panic(err)
		}
		log.Println("Removed Cognito triggers from user pool.")
	} else {
		log.Println("Be sure to remove resources when you're done with them to avoid unexpected charges!")
	}
}
```
+ Weitere API-Informationen finden Sie in den folgenden Themen der *AWS SDK für Go -API-Referenz*.
  + [AdminCreateUser](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.AdminCreateUser)
  + [AdminSetUserPassword](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.AdminSetUserPassword)
  + [DeleteUser](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.DeleteUser)
  + [InitiateAuth](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.InitiateAuth)
  + [UpdateUserPool](https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider#Client.UpdateUserPool)