Amazon RDS examples using SDK for Go V2

package main

import (
	"context"
	"fmt"

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

// main uses the AWS SDK for Go V2 to create an Amazon Relational Database Service (Amazon RDS)
// client and list up to 20 DB instances 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
	}
	rdsClient := rds.NewFromConfig(sdkConfig)
	const maxInstances = 20
	fmt.Printf("Let's list up to %v DB instances.\n", maxInstances)
	output, err := rdsClient.DescribeDBInstances(ctx,
		&rds.DescribeDBInstancesInput{MaxRecords: aws.Int32(maxInstances)})
	if err != nil {
		fmt.Printf("Couldn't list DB instances: %v\n", err)
		return
	}
	if len(output.DBInstances) == 0 {
		fmt.Println("No DB instances found.")
	} else {
		for _, instance := range output.DBInstances {
			fmt.Printf("DB instance %v has database %v.\n", *instance.DBInstanceIdentifier,
				*instance.DBName)
		}
	}
}

Run an interactive scenario at a command prompt.

import (
	"context"
	"fmt"
	"log"
	"sort"
	"strconv"
	"strings"
	"time"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/rds"
	"github.com/aws/aws-sdk-go-v2/service/rds/types"
	"github.com/awsdocs/aws-doc-sdk-examples/gov2/demotools"
	"github.com/awsdocs/aws-doc-sdk-examples/gov2/rds/actions"
	"github.com/google/uuid"
)

// GetStartedInstances is an interactive example that shows you how to use the AWS SDK for Go
// with Amazon Relation Database Service (Amazon RDS) to do the following:
//
//  1. Create a custom DB parameter group and set parameter values.
//  2. Create a DB instance that is configured to use the parameter group. The DB instance
//     also contains a database.
//  3. Take a snapshot of the DB instance.
//  4. Delete the DB instance and parameter group.
type GetStartedInstances struct {
	sdkConfig  aws.Config
	instances  actions.DbInstances
	questioner demotools.IQuestioner
	helper     IScenarioHelper
	isTestRun  bool
}

// NewGetStartedInstances constructs a GetStartedInstances instance from a configuration.
// It uses the specified config to get an Amazon RDS
// client and create wrappers for the actions used in the scenario.
func NewGetStartedInstances(sdkConfig aws.Config, questioner demotools.IQuestioner,
	helper IScenarioHelper) GetStartedInstances {
	rdsClient := rds.NewFromConfig(sdkConfig)
	return GetStartedInstances{
		sdkConfig:  sdkConfig,
		instances:  actions.DbInstances{RdsClient: rdsClient},
		questioner: questioner,
		helper:     helper,
	}
}

// Run runs the interactive scenario.
func (scenario GetStartedInstances) Run(ctx context.Context, dbEngine string, parameterGroupName string,
	instanceName string, dbName string) {
	defer func() {
		if r := recover(); r != nil {
			log.Println("Something went wrong with the demo.")
		}
	}()

	log.Println(strings.Repeat("-", 88))
	log.Println("Welcome to the Amazon Relational Database Service (Amazon RDS) DB Instance demo.")
	log.Println(strings.Repeat("-", 88))

	parameterGroup := scenario.CreateParameterGroup(ctx, dbEngine, parameterGroupName)
	scenario.SetUserParameters(ctx, parameterGroupName)
	instance := scenario.CreateInstance(ctx, instanceName, dbEngine, dbName, parameterGroup)
	scenario.DisplayConnection(instance)
	scenario.CreateSnapshot(ctx, instance)
	scenario.Cleanup(ctx, instance, parameterGroup)

	log.Println(strings.Repeat("-", 88))
	log.Println("Thanks for watching!")
	log.Println(strings.Repeat("-", 88))
}

// CreateParameterGroup shows how to get available engine versions for a specified
// database engine and create a DB parameter group that is compatible with a
// selected engine family.
func (scenario GetStartedInstances) CreateParameterGroup(ctx context.Context, dbEngine string,
	parameterGroupName string) *types.DBParameterGroup {

	log.Printf("Checking for an existing DB parameter group named %v.\n",
		parameterGroupName)
	parameterGroup, err := scenario.instances.GetParameterGroup(ctx, parameterGroupName)
	if err != nil {
		panic(err)
	}
	if parameterGroup == nil {
		log.Printf("Getting available database engine versions for %v.\n", dbEngine)
		engineVersions, err := scenario.instances.GetEngineVersions(ctx, dbEngine, "")
		if err != nil {
			panic(err)
		}

		familySet := map[string]struct{}{}
		for _, family := range engineVersions {
			familySet[*family.DBParameterGroupFamily] = struct{}{}
		}
		var families []string
		for family := range familySet {
			families = append(families, family)
		}
		sort.Strings(families)
		familyIndex := scenario.questioner.AskChoice("Which family do you want to use?\n", families)
		log.Println("Creating a DB parameter group.")
		_, err = scenario.instances.CreateParameterGroup(
			ctx, parameterGroupName, families[familyIndex], "Example parameter group.")
		if err != nil {
			panic(err)
		}
		parameterGroup, err = scenario.instances.GetParameterGroup(ctx, parameterGroupName)
		if err != nil {
			panic(err)
		}
	}
	log.Printf("Parameter group %v:\n", *parameterGroup.DBParameterGroupFamily)
	log.Printf("\tName: %v\n", *parameterGroup.DBParameterGroupName)
	log.Printf("\tARN: %v\n", *parameterGroup.DBParameterGroupArn)
	log.Printf("\tFamily: %v\n", *parameterGroup.DBParameterGroupFamily)
	log.Printf("\tDescription: %v\n", *parameterGroup.Description)
	log.Println(strings.Repeat("-", 88))
	return parameterGroup
}

// SetUserParameters shows how to get the parameters contained in a custom parameter
// group and update some of the parameter values in the group.
func (scenario GetStartedInstances) SetUserParameters(ctx context.Context, parameterGroupName string) {
	log.Println("Let's set some parameter values in your parameter group.")
	dbParameters, err := scenario.instances.GetParameters(ctx, parameterGroupName, "")
	if err != nil {
		panic(err)
	}
	var updateParams []types.Parameter
	for _, dbParam := range dbParameters {
		if strings.HasPrefix(*dbParam.ParameterName, "auto_increment") &&
			*dbParam.IsModifiable && *dbParam.DataType == "integer" {
			log.Printf("The %v parameter is described as:\n\t%v",
				*dbParam.ParameterName, *dbParam.Description)
			rangeSplit := strings.Split(*dbParam.AllowedValues, "-")
			lower, _ := strconv.Atoi(rangeSplit[0])
			upper, _ := strconv.Atoi(rangeSplit[1])
			newValue := scenario.questioner.AskInt(
				fmt.Sprintf("Enter a value between %v and %v:", lower, upper),
				demotools.InIntRange{Lower: lower, Upper: upper})
			dbParam.ParameterValue = aws.String(strconv.Itoa(newValue))
			updateParams = append(updateParams, dbParam)
		}
	}
	err = scenario.instances.UpdateParameters(ctx, parameterGroupName, updateParams)
	if err != nil {
		panic(err)
	}
	log.Println("To get a list of parameters that you set previously, specify a source of 'user'.")
	userParameters, err := scenario.instances.GetParameters(ctx, parameterGroupName, "user")
	if err != nil {
		panic(err)
	}
	log.Println("Here are the parameters you set:")
	for _, param := range userParameters {
		log.Printf("\t%v: %v\n", *param.ParameterName, *param.ParameterValue)
	}
	log.Println(strings.Repeat("-", 88))
}

// CreateInstance shows how to create a DB instance that contains a database of a
// specified type. The database is also configured to use a custom DB parameter group.
func (scenario GetStartedInstances) CreateInstance(ctx context.Context, instanceName string, dbEngine string,
	dbName string, parameterGroup *types.DBParameterGroup) *types.DBInstance {

	log.Println("Checking for an existing DB instance.")
	instance, err := scenario.instances.GetInstance(ctx, instanceName)
	if err != nil {
		panic(err)
	}
	if instance == nil {
		adminUsername := scenario.questioner.Ask(
			"Enter an administrator username for the database: ", demotools.NotEmpty{})
		adminPassword := scenario.questioner.AskPassword(
			"Enter a password for the administrator (at least 8 characters): ", 7)
		engineVersions, err := scenario.instances.GetEngineVersions(ctx, dbEngine,
			*parameterGroup.DBParameterGroupFamily)
		if err != nil {
			panic(err)
		}
		var engineChoices []string
		for _, engine := range engineVersions {
			engineChoices = append(engineChoices, *engine.EngineVersion)
		}
		engineIndex := scenario.questioner.AskChoice(
			"The available engines for your parameter group are:\n", engineChoices)
		engineSelection := engineVersions[engineIndex]
		instOpts, err := scenario.instances.GetOrderableInstances(ctx, *engineSelection.Engine,
			*engineSelection.EngineVersion)
		if err != nil {
			panic(err)
		}
		optSet := map[string]struct{}{}
		for _, opt := range instOpts {
			if strings.Contains(*opt.DBInstanceClass, "micro") {
				optSet[*opt.DBInstanceClass] = struct{}{}
			}
		}
		var optChoices []string
		for opt := range optSet {
			optChoices = append(optChoices, opt)
		}
		sort.Strings(optChoices)
		optIndex := scenario.questioner.AskChoice(
			"The available micro DB instance classes for your database engine are:\n", optChoices)
		storageType := "standard"
		allocatedStorage := int32(5)
		log.Printf("Creating a DB instance named %v and database %v.\n"+
			"The DB instance is configured to use your custom parameter group %v,\n"+
			"selected engine %v,\n"+
			"selected DB instance class %v,"+
			"and %v GiB of %v storage.\n"+
			"This typically takes several minutes.",
			instanceName, dbName, *parameterGroup.DBParameterGroupName, *engineSelection.EngineVersion,
			optChoices[optIndex], allocatedStorage, storageType)
		instance, err = scenario.instances.CreateInstance(
			ctx, instanceName, dbName, *engineSelection.Engine, *engineSelection.EngineVersion,
			*parameterGroup.DBParameterGroupName, optChoices[optIndex], storageType,
			allocatedStorage, adminUsername, adminPassword)
		if err != nil {
			panic(err)
		}
		for *instance.DBInstanceStatus != "available" {
			scenario.helper.Pause(30)
			instance, err = scenario.instances.GetInstance(ctx, instanceName)
			if err != nil {
				panic(err)
			}
		}
		log.Println("Instance created and available.")
	}
	log.Println("Instance data:")
	log.Printf("\tDBInstanceIdentifier: %v\n", *instance.DBInstanceIdentifier)
	log.Printf("\tARN: %v\n", *instance.DBInstanceArn)
	log.Printf("\tStatus: %v\n", *instance.DBInstanceStatus)
	log.Printf("\tEngine: %v\n", *instance.Engine)
	log.Printf("\tEngine version: %v\n", *instance.EngineVersion)
	log.Println(strings.Repeat("-", 88))
	return instance
}

// DisplayConnection displays connection information about a DB instance and tips
// on how to connect to it.
func (scenario GetStartedInstances) DisplayConnection(instance *types.DBInstance) {
	log.Println(
		"You can now connect to your database by using your favorite MySQL client.\n" +
			"One way to connect is by using the 'mysql' shell on an Amazon EC2 instance\n" +
			"that is running in the same VPC as your DB instance. Pass the endpoint,\n" +
			"port, and administrator username to 'mysql'. Then, enter your password\n" +
			"when prompted:")
	log.Printf("\n\tmysql -h %v -P %v -u %v -p\n",
		*instance.Endpoint.Address, instance.Endpoint.Port, *instance.MasterUsername)
	log.Println("For more information, see the User Guide for RDS:\n" +
		"\thttps://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_GettingStarted.CreatingConnecting.MySQL.html#CHAP_GettingStarted.Connecting.MySQL")
	log.Println(strings.Repeat("-", 88))
}

// CreateSnapshot shows how to create a DB instance snapshot and wait until it's available.
func (scenario GetStartedInstances) CreateSnapshot(ctx context.Context, instance *types.DBInstance) {
	if scenario.questioner.AskBool(
		"Do you want to create a snapshot of your DB instance (y/n)? ", "y") {
		snapshotId := fmt.Sprintf("%v-%v", *instance.DBInstanceIdentifier, scenario.helper.UniqueId())
		log.Printf("Creating a snapshot named %v. This typically takes a few minutes.\n", snapshotId)
		snapshot, err := scenario.instances.CreateSnapshot(ctx, *instance.DBInstanceIdentifier, snapshotId)
		if err != nil {
			panic(err)
		}
		for *snapshot.Status != "available" {
			scenario.helper.Pause(30)
			snapshot, err = scenario.instances.GetSnapshot(ctx, snapshotId)
			if err != nil {
				panic(err)
			}
		}
		log.Println("Snapshot data:")
		log.Printf("\tDBSnapshotIdentifier: %v\n", *snapshot.DBSnapshotIdentifier)
		log.Printf("\tARN: %v\n", *snapshot.DBSnapshotArn)
		log.Printf("\tStatus: %v\n", *snapshot.Status)
		log.Printf("\tEngine: %v\n", *snapshot.Engine)
		log.Printf("\tEngine version: %v\n", *snapshot.EngineVersion)
		log.Printf("\tDBInstanceIdentifier: %v\n", *snapshot.DBInstanceIdentifier)
		log.Printf("\tSnapshotCreateTime: %v\n", *snapshot.SnapshotCreateTime)
		log.Println(strings.Repeat("-", 88))
	}
}

// Cleanup shows how to clean up a DB instance and DB parameter group.
// Before the DB parameter group can be deleted, all associated DB instances must first be deleted.
func (scenario GetStartedInstances) Cleanup(
	ctx context.Context, instance *types.DBInstance, parameterGroup *types.DBParameterGroup) {

	if scenario.questioner.AskBool(
		"\nDo you want to delete the database instance and parameter group (y/n)? ", "y") {
		log.Printf("Deleting database instance %v.\n", *instance.DBInstanceIdentifier)
		err := scenario.instances.DeleteInstance(ctx, *instance.DBInstanceIdentifier)
		if err != nil {
			panic(err)
		}
		log.Println(
			"Waiting for the DB instance to delete. This typically takes several minutes.")
		for instance != nil {
			scenario.helper.Pause(30)
			instance, err = scenario.instances.GetInstance(ctx, *instance.DBInstanceIdentifier)
			if err != nil {
				panic(err)
			}
		}
		log.Printf("Deleting parameter group %v.", *parameterGroup.DBParameterGroupName)
		err = scenario.instances.DeleteParameterGroup(ctx, *parameterGroup.DBParameterGroupName)
		if err != nil {
			panic(err)
		}
	}
}

// IScenarioHelper abstracts the function from a scenario so that it
// can be mocked for unit testing.
type IScenarioHelper interface {
	Pause(secs int)
	UniqueId() string
}
type ScenarioHelper struct{}

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

// UniqueId returns a new UUID.
func (helper ScenarioHelper) UniqueId() string {
	return uuid.New().String()
}

Define functions that are called by the scenario to manage Amazon RDS actions.

import (
	"context"
	"errors"
	"log"

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

type DbInstances struct {
	RdsClient *rds.Client
}


// GetParameterGroup gets a DB parameter group by name.
func (instances *DbInstances) GetParameterGroup(ctx context.Context, parameterGroupName string) (
	*types.DBParameterGroup, error) {
	output, err := instances.RdsClient.DescribeDBParameterGroups(
		ctx, &rds.DescribeDBParameterGroupsInput{
			DBParameterGroupName: aws.String(parameterGroupName),
		})
	if err != nil {
		var notFoundError *types.DBParameterGroupNotFoundFault
		if errors.As(err, &notFoundError) {
			log.Printf("Parameter group %v does not exist.\n", parameterGroupName)
			err = nil
		} else {
			log.Printf("Error getting parameter group %v: %v\n", parameterGroupName, err)
		}
		return nil, err
	} else {
		return &output.DBParameterGroups[0], err
	}
}



// CreateParameterGroup creates a DB parameter group that is based on the specified
// parameter group family.
func (instances *DbInstances) CreateParameterGroup(
	ctx context.Context, parameterGroupName string, parameterGroupFamily string, description string) (
	*types.DBParameterGroup, error) {

	output, err := instances.RdsClient.CreateDBParameterGroup(ctx,
		&rds.CreateDBParameterGroupInput{
			DBParameterGroupName:   aws.String(parameterGroupName),
			DBParameterGroupFamily: aws.String(parameterGroupFamily),
			Description:            aws.String(description),
		})
	if err != nil {
		log.Printf("Couldn't create parameter group %v: %v\n", parameterGroupName, err)
		return nil, err
	} else {
		return output.DBParameterGroup, err
	}
}



// DeleteParameterGroup deletes the named DB parameter group.
func (instances *DbInstances) DeleteParameterGroup(ctx context.Context, parameterGroupName string) error {
	_, err := instances.RdsClient.DeleteDBParameterGroup(ctx,
		&rds.DeleteDBParameterGroupInput{
			DBParameterGroupName: aws.String(parameterGroupName),
		})
	if err != nil {
		log.Printf("Couldn't delete parameter group %v: %v\n", parameterGroupName, err)
		return err
	} else {
		return nil
	}
}



// GetParameters gets the parameters that are contained in a DB parameter group.
func (instances *DbInstances) GetParameters(ctx context.Context, parameterGroupName string, source string) (
	[]types.Parameter, error) {

	var output *rds.DescribeDBParametersOutput
	var params []types.Parameter
	var err error
	parameterPaginator := rds.NewDescribeDBParametersPaginator(instances.RdsClient,
		&rds.DescribeDBParametersInput{
			DBParameterGroupName: aws.String(parameterGroupName),
			Source:               aws.String(source),
		})
	for parameterPaginator.HasMorePages() {
		output, err = parameterPaginator.NextPage(ctx)
		if err != nil {
			log.Printf("Couldn't get parameters for %v: %v\n", parameterGroupName, err)
			break
		} else {
			params = append(params, output.Parameters...)
		}
	}
	return params, err
}



// UpdateParameters updates parameters in a named DB parameter group.
func (instances *DbInstances) UpdateParameters(ctx context.Context, parameterGroupName string, params []types.Parameter) error {
	_, err := instances.RdsClient.ModifyDBParameterGroup(ctx,
		&rds.ModifyDBParameterGroupInput{
			DBParameterGroupName: aws.String(parameterGroupName),
			Parameters:           params,
		})
	if err != nil {
		log.Printf("Couldn't update parameters in %v: %v\n", parameterGroupName, err)
		return err
	} else {
		return nil
	}
}



// CreateSnapshot creates a snapshot of a DB instance.
func (instances *DbInstances) CreateSnapshot(ctx context.Context, instanceName string, snapshotName string) (
	*types.DBSnapshot, error) {
	output, err := instances.RdsClient.CreateDBSnapshot(ctx, &rds.CreateDBSnapshotInput{
		DBInstanceIdentifier: aws.String(instanceName),
		DBSnapshotIdentifier: aws.String(snapshotName),
	})
	if err != nil {
		log.Printf("Couldn't create snapshot %v: %v\n", snapshotName, err)
		return nil, err
	} else {
		return output.DBSnapshot, nil
	}
}



// GetSnapshot gets a DB instance snapshot.
func (instances *DbInstances) GetSnapshot(ctx context.Context, snapshotName string) (*types.DBSnapshot, error) {
	output, err := instances.RdsClient.DescribeDBSnapshots(ctx,
		&rds.DescribeDBSnapshotsInput{
			DBSnapshotIdentifier: aws.String(snapshotName),
		})
	if err != nil {
		log.Printf("Couldn't get snapshot %v: %v\n", snapshotName, err)
		return nil, err
	} else {
		return &output.DBSnapshots[0], nil
	}
}



// CreateInstance creates a DB instance.
func (instances *DbInstances) CreateInstance(ctx context.Context, instanceName string, dbName string,
	dbEngine string, dbEngineVersion string, parameterGroupName string, dbInstanceClass string,
	storageType string, allocatedStorage int32, adminName string, adminPassword string) (
	*types.DBInstance, error) {
	output, err := instances.RdsClient.CreateDBInstance(ctx, &rds.CreateDBInstanceInput{
		DBInstanceIdentifier: aws.String(instanceName),
		DBName:               aws.String(dbName),
		DBParameterGroupName: aws.String(parameterGroupName),
		Engine:               aws.String(dbEngine),
		EngineVersion:        aws.String(dbEngineVersion),
		DBInstanceClass:      aws.String(dbInstanceClass),
		StorageType:          aws.String(storageType),
		AllocatedStorage:     aws.Int32(allocatedStorage),
		MasterUsername:       aws.String(adminName),
		MasterUserPassword:   aws.String(adminPassword),
	})
	if err != nil {
		log.Printf("Couldn't create instance %v: %v\n", instanceName, err)
		return nil, err
	} else {
		return output.DBInstance, nil
	}
}



// GetInstance gets data about a DB instance.
func (instances *DbInstances) GetInstance(ctx context.Context, instanceName string) (
	*types.DBInstance, error) {
	output, err := instances.RdsClient.DescribeDBInstances(ctx,
		&rds.DescribeDBInstancesInput{
			DBInstanceIdentifier: aws.String(instanceName),
		})
	if err != nil {
		var notFoundError *types.DBInstanceNotFoundFault
		if errors.As(err, &notFoundError) {
			log.Printf("DB instance %v does not exist.\n", instanceName)
			err = nil
		} else {
			log.Printf("Couldn't get instance %v: %v\n", instanceName, err)
		}
		return nil, err
	} else {
		return &output.DBInstances[0], nil
	}
}



// DeleteInstance deletes a DB instance.
func (instances *DbInstances) DeleteInstance(ctx context.Context, instanceName string) error {
	_, err := instances.RdsClient.DeleteDBInstance(ctx, &rds.DeleteDBInstanceInput{
		DBInstanceIdentifier:   aws.String(instanceName),
		SkipFinalSnapshot:      aws.Bool(true),
		DeleteAutomatedBackups: aws.Bool(true),
	})
	if err != nil {
		log.Printf("Couldn't delete instance %v: %v\n", instanceName, err)
		return err
	} else {
		return nil
	}
}



// GetEngineVersions gets database engine versions that are available for the specified engine
// and parameter group family.
func (instances *DbInstances) GetEngineVersions(ctx context.Context, engine string, parameterGroupFamily string) (
	[]types.DBEngineVersion, error) {
	output, err := instances.RdsClient.DescribeDBEngineVersions(ctx,
		&rds.DescribeDBEngineVersionsInput{
			Engine:                 aws.String(engine),
			DBParameterGroupFamily: aws.String(parameterGroupFamily),
		})
	if err != nil {
		log.Printf("Couldn't get engine versions for %v: %v\n", engine, err)
		return nil, err
	} else {
		return output.DBEngineVersions, nil
	}
}



// GetOrderableInstances uses a paginator to get DB instance options that can be used to create DB instances that are
// compatible with a set of specifications.
func (instances *DbInstances) GetOrderableInstances(ctx context.Context, engine string, engineVersion string) (
	[]types.OrderableDBInstanceOption, error) {

	var output *rds.DescribeOrderableDBInstanceOptionsOutput
	var instanceOptions []types.OrderableDBInstanceOption
	var err error
	orderablePaginator := rds.NewDescribeOrderableDBInstanceOptionsPaginator(instances.RdsClient,
		&rds.DescribeOrderableDBInstanceOptionsInput{
			Engine:        aws.String(engine),
			EngineVersion: aws.String(engineVersion),
		})
	for orderablePaginator.HasMorePages() {
		output, err = orderablePaginator.NextPage(ctx)
		if err != nil {
			log.Printf("Couldn't get orderable DB instance options: %v\n", err)
			break
		} else {
			instanceOptions = append(instanceOptions, output.OrderableDBInstanceOptions...)
		}
	}
	return instanceOptions, err
}

import (
	"context"
	"errors"
	"log"

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

type DbInstances struct {
	RdsClient *rds.Client
}



// CreateInstance creates a DB instance.
func (instances *DbInstances) CreateInstance(ctx context.Context, instanceName string, dbName string,
	dbEngine string, dbEngineVersion string, parameterGroupName string, dbInstanceClass string,
	storageType string, allocatedStorage int32, adminName string, adminPassword string) (
	*types.DBInstance, error) {
	output, err := instances.RdsClient.CreateDBInstance(ctx, &rds.CreateDBInstanceInput{
		DBInstanceIdentifier: aws.String(instanceName),
		DBName:               aws.String(dbName),
		DBParameterGroupName: aws.String(parameterGroupName),
		Engine:               aws.String(dbEngine),
		EngineVersion:        aws.String(dbEngineVersion),
		DBInstanceClass:      aws.String(dbInstanceClass),
		StorageType:          aws.String(storageType),
		AllocatedStorage:     aws.Int32(allocatedStorage),
		MasterUsername:       aws.String(adminName),
		MasterUserPassword:   aws.String(adminPassword),
	})
	if err != nil {
		log.Printf("Couldn't create instance %v: %v\n", instanceName, err)
		return nil, err
	} else {
		return output.DBInstance, nil
	}
}

import (
	"context"
	"errors"
	"log"

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

type DbInstances struct {
	RdsClient *rds.Client
}



// CreateParameterGroup creates a DB parameter group that is based on the specified
// parameter group family.
func (instances *DbInstances) CreateParameterGroup(
	ctx context.Context, parameterGroupName string, parameterGroupFamily string, description string) (
	*types.DBParameterGroup, error) {

	output, err := instances.RdsClient.CreateDBParameterGroup(ctx,
		&rds.CreateDBParameterGroupInput{
			DBParameterGroupName:   aws.String(parameterGroupName),
			DBParameterGroupFamily: aws.String(parameterGroupFamily),
			Description:            aws.String(description),
		})
	if err != nil {
		log.Printf("Couldn't create parameter group %v: %v\n", parameterGroupName, err)
		return nil, err
	} else {
		return output.DBParameterGroup, err
	}
}

import (
	"context"
	"errors"
	"log"

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

type DbInstances struct {
	RdsClient *rds.Client
}



// CreateSnapshot creates a snapshot of a DB instance.
func (instances *DbInstances) CreateSnapshot(ctx context.Context, instanceName string, snapshotName string) (
	*types.DBSnapshot, error) {
	output, err := instances.RdsClient.CreateDBSnapshot(ctx, &rds.CreateDBSnapshotInput{
		DBInstanceIdentifier: aws.String(instanceName),
		DBSnapshotIdentifier: aws.String(snapshotName),
	})
	if err != nil {
		log.Printf("Couldn't create snapshot %v: %v\n", snapshotName, err)
		return nil, err
	} else {
		return output.DBSnapshot, nil
	}
}

import (
	"context"
	"errors"
	"log"

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

type DbInstances struct {
	RdsClient *rds.Client
}



// DeleteInstance deletes a DB instance.
func (instances *DbInstances) DeleteInstance(ctx context.Context, instanceName string) error {
	_, err := instances.RdsClient.DeleteDBInstance(ctx, &rds.DeleteDBInstanceInput{
		DBInstanceIdentifier:   aws.String(instanceName),
		SkipFinalSnapshot:      aws.Bool(true),
		DeleteAutomatedBackups: aws.Bool(true),
	})
	if err != nil {
		log.Printf("Couldn't delete instance %v: %v\n", instanceName, err)
		return err
	} else {
		return nil
	}
}

import (
	"context"
	"errors"
	"log"

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

type DbInstances struct {
	RdsClient *rds.Client
}



// DeleteParameterGroup deletes the named DB parameter group.
func (instances *DbInstances) DeleteParameterGroup(ctx context.Context, parameterGroupName string) error {
	_, err := instances.RdsClient.DeleteDBParameterGroup(ctx,
		&rds.DeleteDBParameterGroupInput{
			DBParameterGroupName: aws.String(parameterGroupName),
		})
	if err != nil {
		log.Printf("Couldn't delete parameter group %v: %v\n", parameterGroupName, err)
		return err
	} else {
		return nil
	}
}

import (
	"context"
	"errors"
	"log"

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

type DbInstances struct {
	RdsClient *rds.Client
}



// GetEngineVersions gets database engine versions that are available for the specified engine
// and parameter group family.
func (instances *DbInstances) GetEngineVersions(ctx context.Context, engine string, parameterGroupFamily string) (
	[]types.DBEngineVersion, error) {
	output, err := instances.RdsClient.DescribeDBEngineVersions(ctx,
		&rds.DescribeDBEngineVersionsInput{
			Engine:                 aws.String(engine),
			DBParameterGroupFamily: aws.String(parameterGroupFamily),
		})
	if err != nil {
		log.Printf("Couldn't get engine versions for %v: %v\n", engine, err)
		return nil, err
	} else {
		return output.DBEngineVersions, nil
	}
}

import (
	"context"
	"errors"
	"log"

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

type DbInstances struct {
	RdsClient *rds.Client
}



// GetInstance gets data about a DB instance.
func (instances *DbInstances) GetInstance(ctx context.Context, instanceName string) (
	*types.DBInstance, error) {
	output, err := instances.RdsClient.DescribeDBInstances(ctx,
		&rds.DescribeDBInstancesInput{
			DBInstanceIdentifier: aws.String(instanceName),
		})
	if err != nil {
		var notFoundError *types.DBInstanceNotFoundFault
		if errors.As(err, &notFoundError) {
			log.Printf("DB instance %v does not exist.\n", instanceName)
			err = nil
		} else {
			log.Printf("Couldn't get instance %v: %v\n", instanceName, err)
		}
		return nil, err
	} else {
		return &output.DBInstances[0], nil
	}
}

import (
	"context"
	"errors"
	"log"

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

type DbInstances struct {
	RdsClient *rds.Client
}



// GetParameterGroup gets a DB parameter group by name.
func (instances *DbInstances) GetParameterGroup(ctx context.Context, parameterGroupName string) (
	*types.DBParameterGroup, error) {
	output, err := instances.RdsClient.DescribeDBParameterGroups(
		ctx, &rds.DescribeDBParameterGroupsInput{
			DBParameterGroupName: aws.String(parameterGroupName),
		})
	if err != nil {
		var notFoundError *types.DBParameterGroupNotFoundFault
		if errors.As(err, &notFoundError) {
			log.Printf("Parameter group %v does not exist.\n", parameterGroupName)
			err = nil
		} else {
			log.Printf("Error getting parameter group %v: %v\n", parameterGroupName, err)
		}
		return nil, err
	} else {
		return &output.DBParameterGroups[0], err
	}
}

import (
	"context"
	"errors"
	"log"

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

type DbInstances struct {
	RdsClient *rds.Client
}



// GetParameters gets the parameters that are contained in a DB parameter group.
func (instances *DbInstances) GetParameters(ctx context.Context, parameterGroupName string, source string) (
	[]types.Parameter, error) {

	var output *rds.DescribeDBParametersOutput
	var params []types.Parameter
	var err error
	parameterPaginator := rds.NewDescribeDBParametersPaginator(instances.RdsClient,
		&rds.DescribeDBParametersInput{
			DBParameterGroupName: aws.String(parameterGroupName),
			Source:               aws.String(source),
		})
	for parameterPaginator.HasMorePages() {
		output, err = parameterPaginator.NextPage(ctx)
		if err != nil {
			log.Printf("Couldn't get parameters for %v: %v\n", parameterGroupName, err)
			break
		} else {
			params = append(params, output.Parameters...)
		}
	}
	return params, err
}

import (
	"context"
	"errors"
	"log"

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

type DbInstances struct {
	RdsClient *rds.Client
}



// GetSnapshot gets a DB instance snapshot.
func (instances *DbInstances) GetSnapshot(ctx context.Context, snapshotName string) (*types.DBSnapshot, error) {
	output, err := instances.RdsClient.DescribeDBSnapshots(ctx,
		&rds.DescribeDBSnapshotsInput{
			DBSnapshotIdentifier: aws.String(snapshotName),
		})
	if err != nil {
		log.Printf("Couldn't get snapshot %v: %v\n", snapshotName, err)
		return nil, err
	} else {
		return &output.DBSnapshots[0], nil
	}
}

import (
	"context"
	"errors"
	"log"

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

type DbInstances struct {
	RdsClient *rds.Client
}



// GetOrderableInstances uses a paginator to get DB instance options that can be used to create DB instances that are
// compatible with a set of specifications.
func (instances *DbInstances) GetOrderableInstances(ctx context.Context, engine string, engineVersion string) (
	[]types.OrderableDBInstanceOption, error) {

	var output *rds.DescribeOrderableDBInstanceOptionsOutput
	var instanceOptions []types.OrderableDBInstanceOption
	var err error
	orderablePaginator := rds.NewDescribeOrderableDBInstanceOptionsPaginator(instances.RdsClient,
		&rds.DescribeOrderableDBInstanceOptionsInput{
			Engine:        aws.String(engine),
			EngineVersion: aws.String(engineVersion),
		})
	for orderablePaginator.HasMorePages() {
		output, err = orderablePaginator.NextPage(ctx)
		if err != nil {
			log.Printf("Couldn't get orderable DB instance options: %v\n", err)
			break
		} else {
			instanceOptions = append(instanceOptions, output.OrderableDBInstanceOptions...)
		}
	}
	return instanceOptions, err
}

import (
	"context"
	"errors"
	"log"

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

type DbInstances struct {
	RdsClient *rds.Client
}



// UpdateParameters updates parameters in a named DB parameter group.
func (instances *DbInstances) UpdateParameters(ctx context.Context, parameterGroupName string, params []types.Parameter) error {
	_, err := instances.RdsClient.ModifyDBParameterGroup(ctx,
		&rds.ModifyDBParameterGroupInput{
			DBParameterGroupName: aws.String(parameterGroupName),
			Parameters:           params,
		})
	if err != nil {
		log.Printf("Couldn't update parameters in %v: %v\n", parameterGroupName, err)
		return err
	} else {
		return nil
	}
}

Connecting to an Amazon RDS database in a Lambda function using Go.

/*
Golang v2 code here.
*/

package main

import (
	"context"
	"database/sql"
	"encoding/json"
	"fmt"
	"os"

	"github.com/aws/aws-lambda-go/lambda"
	"github.com/aws/aws-sdk-go-v2/config"
	"github.com/aws/aws-sdk-go-v2/feature/rds/auth"
	_ "github.com/go-sql-driver/mysql"
)

type MyEvent struct {
	Name string `json:"name"`
}

func HandleRequest(event *MyEvent) (map[string]interface{}, error) {

	var dbName string = os.Getenv("DatabaseName")
	var dbUser string = os.Getenv("DatabaseUser")
	var dbHost string = os.Getenv("DBHost") // Add hostname without https
	var dbPort int = os.Getenv("Port")      // Add port number
	var dbEndpoint string = fmt.Sprintf("%s:%d", dbHost, dbPort)
	var region string = os.Getenv("AWS_REGION")

	cfg, err := config.LoadDefaultConfig(context.TODO())
	if err != nil {
		panic("configuration error: " + err.Error())
	}

	authenticationToken, err := auth.BuildAuthToken(
		context.TODO(), dbEndpoint, region, dbUser, cfg.Credentials)
	if err != nil {
		panic("failed to create authentication token: " + err.Error())
	}

	dsn := fmt.Sprintf("%s:%s@tcp(%s)/%s?tls=true&allowCleartextPasswords=true",
		dbUser, authenticationToken, dbEndpoint, dbName,
	)

	db, err := sql.Open("mysql", dsn)
	if err != nil {
		panic(err)
	}

	defer db.Close()

	var sum int
	err = db.QueryRow("SELECT ?+? AS sum", 3, 2).Scan(&sum)
	if err != nil {
		panic(err)
	}
	s := fmt.Sprint(sum)
	message := fmt.Sprintf("The selected sum is: %s", s)

	messageBytes, err := json.Marshal(message)
	if err != nil {
		return nil, err
	}

	messageString := string(messageBytes)
	return map[string]interface{}{
		"statusCode": 200,
		"headers":    map[string]string{"Content-Type": "application/json"},
		"body":       messageString,
	}, nil
}

func main() {
	lambda.Start(HandleRequest)
}