使用 SDK for Go V2 的 Aurora 範例

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 Aurora client and list up to 20
// DB clusters 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
	}
	auroraClient := rds.NewFromConfig(sdkConfig)
	const maxClusters = 20
	fmt.Printf("Let's list up to %v DB clusters.\n", maxClusters)
	output, err := auroraClient.DescribeDBClusters(
		ctx, &rds.DescribeDBClustersInput{MaxRecords: aws.Int32(maxClusters)})
	if err != nil {
		fmt.Printf("Couldn't list DB clusters: %v\n", err)
		return
	}
	if len(output.DBClusters) == 0 {
		fmt.Println("No DB clusters found.")
	} else {
		for _, cluster := range output.DBClusters {
			fmt.Printf("DB cluster %v has database %v.\n", *cluster.DBClusterIdentifier,
				*cluster.DatabaseName)
		}
	}
}

在命令提示中執行互動式案例。

// GetStartedClusters is an interactive example that shows you how to use the AWS SDK for Go
// with Amazon Aurora to do the following:
//
// 1. Create a custom DB cluster parameter group and set parameter values.
// 2. Create an Aurora DB cluster that is configured to use the parameter group.
// 3. Create a DB instance in the DB cluster that contains a database.
// 4. Take a snapshot of the DB cluster.
// 5. Delete the DB instance, DB cluster, and parameter group.
type GetStartedClusters struct {
	sdkConfig  aws.Config
	dbClusters actions.DbClusters
	questioner demotools.IQuestioner
	helper     IScenarioHelper
	isTestRun  bool
}

// NewGetStartedClusters constructs a GetStartedClusters instance from a configuration.
// It uses the specified config to get an Amazon Relational Database Service (Amazon RDS)
// client and create wrappers for the actions used in the scenario.
func NewGetStartedClusters(sdkConfig aws.Config, questioner demotools.IQuestioner,
	helper IScenarioHelper) GetStartedClusters {
	auroraClient := rds.NewFromConfig(sdkConfig)
	return GetStartedClusters{
		sdkConfig:  sdkConfig,
		dbClusters: actions.DbClusters{AuroraClient: auroraClient},
		questioner: questioner,
		helper:     helper,
	}
}

// Run runs the interactive scenario.
func (scenario GetStartedClusters) Run(ctx context.Context, dbEngine string, parameterGroupName string,
	clusterName 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 Aurora DB Cluster demo.")
	log.Println(strings.Repeat("-", 88))

	parameterGroup := scenario.CreateParameterGroup(ctx, dbEngine, parameterGroupName)
	scenario.SetUserParameters(ctx, parameterGroupName)
	cluster := scenario.CreateCluster(ctx, clusterName, dbEngine, dbName, parameterGroup)
	scenario.helper.Pause(5)
	dbInstance := scenario.CreateInstance(ctx, cluster)
	scenario.DisplayConnection(cluster)
	scenario.CreateSnapshot(ctx, clusterName)
	scenario.Cleanup(ctx, dbInstance, cluster, 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 cluster parameter group that is compatible with a
// selected engine family.
func (scenario GetStartedClusters) CreateParameterGroup(ctx context.Context, dbEngine string,
	parameterGroupName string) *types.DBClusterParameterGroup {

	log.Printf("Checking for an existing DB cluster parameter group named %v.\n",
		parameterGroupName)
	parameterGroup, err := scenario.dbClusters.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.dbClusters.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 cluster parameter group.")
		_, err = scenario.dbClusters.CreateParameterGroup(
			ctx, parameterGroupName, families[familyIndex], "Example parameter group.")
		if err != nil {
			panic(err)
		}
		parameterGroup, err = scenario.dbClusters.GetParameterGroup(ctx, parameterGroupName)
		if err != nil {
			panic(err)
		}
	}
	log.Printf("Parameter group %v:\n", *parameterGroup.DBParameterGroupFamily)
	log.Printf("\tName: %v\n", *parameterGroup.DBClusterParameterGroupName)
	log.Printf("\tARN: %v\n", *parameterGroup.DBClusterParameterGroupArn)
	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 GetStartedClusters) SetUserParameters(ctx context.Context, parameterGroupName string) {
	log.Println("Let's set some parameter values in your parameter group.")
	dbParameters, err := scenario.dbClusters.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.dbClusters.UpdateParameters(ctx, parameterGroupName, updateParams)
	if err != nil {
		panic(err)
	}
	log.Println("You can get a list of parameters you've set by specifying a source of 'user'.")
	userParameters, err := scenario.dbClusters.GetParameters(ctx, parameterGroupName, "user")
	if err != nil {
		panic(err)
	}
	log.Println("Here are the parameters you've set:")
	for _, param := range userParameters {
		log.Printf("\t%v: %v\n", *param.ParameterName, *param.ParameterValue)
	}
	log.Println(strings.Repeat("-", 88))
}

// CreateCluster shows how to create an Aurora DB cluster that contains a database
// of a specified type. The database is also configured to use a custom DB cluster
// parameter group.
func (scenario GetStartedClusters) CreateCluster(ctx context.Context, clusterName string, dbEngine string,
	dbName string, parameterGroup *types.DBClusterParameterGroup) *types.DBCluster {

	log.Println("Checking for an existing DB cluster.")
	cluster, err := scenario.dbClusters.GetDbCluster(ctx, clusterName)
	if err != nil {
		panic(err)
	}
	if cluster == nil {
		adminUsername := scenario.questioner.Ask(
			"Enter an administrator user name for the database: ", demotools.NotEmpty{})
		adminPassword := scenario.questioner.Ask(
			"Enter a password for the administrator (at least 8 characters): ", demotools.NotEmpty{})
		engineVersions, err := scenario.dbClusters.GetEngineVersions(ctx, dbEngine, *parameterGroup.DBParameterGroupFamily)
		if err != nil {
			panic(err)
		}
		var engineChoices []string
		for _, engine := range engineVersions {
			engineChoices = append(engineChoices, *engine.EngineVersion)
		}
		log.Println("The available engines for your parameter group are:")
		engineIndex := scenario.questioner.AskChoice("Which engine do you want to use?\n", engineChoices)
		log.Printf("Creating DB cluster %v and database %v.\n", clusterName, dbName)
		log.Printf("The DB cluster is configured to use\nyour custom parameter group %v\n",
			*parameterGroup.DBClusterParameterGroupName)
		log.Printf("and selected engine %v.\n", engineChoices[engineIndex])
		log.Println("This typically takes several minutes.")
		cluster, err = scenario.dbClusters.CreateDbCluster(
			ctx, clusterName, *parameterGroup.DBClusterParameterGroupName, dbName, dbEngine,
			engineChoices[engineIndex], adminUsername, adminPassword)
		if err != nil {
			panic(err)
		}
		for *cluster.Status != "available" {
			scenario.helper.Pause(30)
			cluster, err = scenario.dbClusters.GetDbCluster(ctx, clusterName)
			if err != nil {
				panic(err)
			}
			log.Println("Cluster created and available.")
		}
	}
	log.Println("Cluster data:")
	log.Printf("\tDBClusterIdentifier: %v\n", *cluster.DBClusterIdentifier)
	log.Printf("\tARN: %v\n", *cluster.DBClusterArn)
	log.Printf("\tStatus: %v\n", *cluster.Status)
	log.Printf("\tEngine: %v\n", *cluster.Engine)
	log.Printf("\tEngine version: %v\n", *cluster.EngineVersion)
	log.Printf("\tDBClusterParameterGroup: %v\n", *cluster.DBClusterParameterGroup)
	log.Printf("\tEngineMode: %v\n", *cluster.EngineMode)
	log.Println(strings.Repeat("-", 88))
	return cluster
}

// CreateInstance shows how to create a DB instance in an existing Aurora DB cluster.
// A new DB cluster contains no DB instances, so you must add one. The first DB instance
// that is added to a DB cluster defaults to a read-write DB instance.
func (scenario GetStartedClusters) CreateInstance(ctx context.Context, cluster *types.DBCluster) *types.DBInstance {
	log.Println("Checking for an existing database instance.")
	dbInstance, err := scenario.dbClusters.GetInstance(ctx, *cluster.DBClusterIdentifier)
	if err != nil {
		panic(err)
	}
	if dbInstance == nil {
		log.Println("Let's create a database instance in your DB cluster.")
		log.Println("First, choose a DB instance type:")
		instOpts, err := scenario.dbClusters.GetOrderableInstances(
			ctx, *cluster.Engine, *cluster.EngineVersion)
		if err != nil {
			panic(err)
		}
		var instChoices []string
		for _, opt := range instOpts {
			instChoices = append(instChoices, *opt.DBInstanceClass)
		}
		slices.Sort(instChoices)
		instChoices = slices.Compact(instChoices)
		instIndex := scenario.questioner.AskChoice(
			"Which DB instance class do you want to use?\n", instChoices)
		log.Println("Creating a database instance. This typically takes several minutes.")
		dbInstance, err = scenario.dbClusters.CreateInstanceInCluster(
			ctx, *cluster.DBClusterIdentifier, *cluster.DBClusterIdentifier, *cluster.Engine,
			instChoices[instIndex])
		if err != nil {
			panic(err)
		}
		for *dbInstance.DBInstanceStatus != "available" {
			scenario.helper.Pause(30)
			dbInstance, err = scenario.dbClusters.GetInstance(ctx, *cluster.DBClusterIdentifier)
			if err != nil {
				panic(err)
			}
		}
	}
	log.Println("Instance data:")
	log.Printf("\tDBInstanceIdentifier: %v\n", *dbInstance.DBInstanceIdentifier)
	log.Printf("\tARN: %v\n", *dbInstance.DBInstanceArn)
	log.Printf("\tStatus: %v\n", *dbInstance.DBInstanceStatus)
	log.Printf("\tEngine: %v\n", *dbInstance.Engine)
	log.Printf("\tEngine version: %v\n", *dbInstance.EngineVersion)
	log.Println(strings.Repeat("-", 88))
	return dbInstance
}

// DisplayConnection displays connection information about an Aurora DB cluster and tips
// on how to connect to it.
func (scenario GetStartedClusters) DisplayConnection(cluster *types.DBCluster) {
	log.Println(
		"You can now connect to your database 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 database cluster. Pass the endpoint,\n" +
			"port, and administrator user name to 'mysql' and enter your password\n" +
			"when prompted:")
	log.Printf("\n\tmysql -h %v -P %v -u %v -p\n",
		*cluster.Endpoint, *cluster.Port, *cluster.MasterUsername)
	log.Println("For more information, see the User Guide for Aurora:\n" +
		"\thttps://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/CHAP_GettingStartedAurora.CreatingConnecting.Aurora.html#CHAP_GettingStartedAurora.Aurora.Connect")
	log.Println(strings.Repeat("-", 88))
}

// CreateSnapshot shows how to create a DB cluster snapshot and wait until it's available.
func (scenario GetStartedClusters) CreateSnapshot(ctx context.Context, clusterName string) {
	if scenario.questioner.AskBool(
		"Do you want to create a snapshot of your DB cluster (y/n)? ", "y") {
		snapshotId := fmt.Sprintf("%v-%v", clusterName, scenario.helper.UniqueId())
		log.Printf("Creating a snapshot named %v. This typically takes a few minutes.\n", snapshotId)
		snapshot, err := scenario.dbClusters.CreateClusterSnapshot(ctx, clusterName, snapshotId)
		if err != nil {
			panic(err)
		}
		for *snapshot.Status != "available" {
			scenario.helper.Pause(30)
			snapshot, err = scenario.dbClusters.GetClusterSnapshot(ctx, snapshotId)
			if err != nil {
				panic(err)
			}
		}
		log.Println("Snapshot data:")
		log.Printf("\tDBClusterSnapshotIdentifier: %v\n", *snapshot.DBClusterSnapshotIdentifier)
		log.Printf("\tARN: %v\n", *snapshot.DBClusterSnapshotArn)
		log.Printf("\tStatus: %v\n", *snapshot.Status)
		log.Printf("\tEngine: %v\n", *snapshot.Engine)
		log.Printf("\tEngine version: %v\n", *snapshot.EngineVersion)
		log.Printf("\tDBClusterIdentifier: %v\n", *snapshot.DBClusterIdentifier)
		log.Printf("\tSnapshotCreateTime: %v\n", *snapshot.SnapshotCreateTime)
		log.Println(strings.Repeat("-", 88))
	}
}

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

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

定義案例所呼叫的函數以管理 Amazon 動作。

type DbClusters struct {
	AuroraClient *rds.Client
}


// GetParameterGroup gets a DB cluster parameter group by name.
func (clusters *DbClusters) GetParameterGroup(ctx context.Context, parameterGroupName string) (
	*types.DBClusterParameterGroup, error) {
	output, err := clusters.AuroraClient.DescribeDBClusterParameterGroups(
		ctx, &rds.DescribeDBClusterParameterGroupsInput{
			DBClusterParameterGroupName: 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.DBClusterParameterGroups[0], err
	}
}


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

	output, err := clusters.AuroraClient.CreateDBClusterParameterGroup(ctx,
		&rds.CreateDBClusterParameterGroupInput{
			DBClusterParameterGroupName: 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.DBClusterParameterGroup, err
	}
}



// DeleteParameterGroup deletes the named DB cluster parameter group.
func (clusters *DbClusters) DeleteParameterGroup(ctx context.Context, parameterGroupName string) error {
	_, err := clusters.AuroraClient.DeleteDBClusterParameterGroup(ctx,
		&rds.DeleteDBClusterParameterGroupInput{
			DBClusterParameterGroupName: 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 cluster parameter group.
func (clusters *DbClusters) GetParameters(ctx context.Context, parameterGroupName string, source string) (
	[]types.Parameter, error) {

	var output *rds.DescribeDBClusterParametersOutput
	var params []types.Parameter
	var err error
	parameterPaginator := rds.NewDescribeDBClusterParametersPaginator(clusters.AuroraClient,
		&rds.DescribeDBClusterParametersInput{
			DBClusterParameterGroupName: aws.String(parameterGroupName),
			Source:                      aws.String(source),
		})
	for parameterPaginator.HasMorePages() {
		output, err = parameterPaginator.NextPage(ctx)
		if err != nil {
			log.Printf("Couldn't get paramaeters for %v: %v\n", parameterGroupName, err)
			break
		} else {
			params = append(params, output.Parameters...)
		}
	}
	return params, err
}



// UpdateParameters updates parameters in a named DB cluster parameter group.
func (clusters *DbClusters) UpdateParameters(ctx context.Context, parameterGroupName string, params []types.Parameter) error {
	_, err := clusters.AuroraClient.ModifyDBClusterParameterGroup(ctx,
		&rds.ModifyDBClusterParameterGroupInput{
			DBClusterParameterGroupName: 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
	}
}



// GetDbCluster gets data about an Aurora DB cluster.
func (clusters *DbClusters) GetDbCluster(ctx context.Context, clusterName string) (*types.DBCluster, error) {
	output, err := clusters.AuroraClient.DescribeDBClusters(ctx,
		&rds.DescribeDBClustersInput{
			DBClusterIdentifier: aws.String(clusterName),
		})
	if err != nil {
		var notFoundError *types.DBClusterNotFoundFault
		if errors.As(err, &notFoundError) {
			log.Printf("DB cluster %v does not exist.\n", clusterName)
			err = nil
		} else {
			log.Printf("Couldn't get DB cluster %v: %v\n", clusterName, err)
		}
		return nil, err
	} else {
		return &output.DBClusters[0], err
	}
}



// CreateDbCluster creates a DB cluster that is configured to use the specified parameter group.
// The newly created DB cluster contains a database that uses the specified engine and
// engine version.
func (clusters *DbClusters) CreateDbCluster(ctx context.Context, clusterName string, parameterGroupName string,
	dbName string, dbEngine string, dbEngineVersion string, adminName string, adminPassword string) (
	*types.DBCluster, error) {

	output, err := clusters.AuroraClient.CreateDBCluster(ctx, &rds.CreateDBClusterInput{
		DBClusterIdentifier:         aws.String(clusterName),
		Engine:                      aws.String(dbEngine),
		DBClusterParameterGroupName: aws.String(parameterGroupName),
		DatabaseName:                aws.String(dbName),
		EngineVersion:               aws.String(dbEngineVersion),
		MasterUserPassword:          aws.String(adminPassword),
		MasterUsername:              aws.String(adminName),
	})
	if err != nil {
		log.Printf("Couldn't create DB cluster %v: %v\n", clusterName, err)
		return nil, err
	} else {
		return output.DBCluster, err
	}
}



// DeleteDbCluster deletes a DB cluster without keeping a final snapshot.
func (clusters *DbClusters) DeleteDbCluster(ctx context.Context, clusterName string) error {
	_, err := clusters.AuroraClient.DeleteDBCluster(ctx, &rds.DeleteDBClusterInput{
		DBClusterIdentifier: aws.String(clusterName),
		SkipFinalSnapshot:   aws.Bool(true),
	})
	if err != nil {
		log.Printf("Couldn't delete DB cluster %v: %v\n", clusterName, err)
		return err
	} else {
		return nil
	}
}



// CreateClusterSnapshot creates a snapshot of a DB cluster.
func (clusters *DbClusters) CreateClusterSnapshot(ctx context.Context, clusterName string, snapshotName string) (
	*types.DBClusterSnapshot, error) {
	output, err := clusters.AuroraClient.CreateDBClusterSnapshot(ctx, &rds.CreateDBClusterSnapshotInput{
		DBClusterIdentifier:         aws.String(clusterName),
		DBClusterSnapshotIdentifier: aws.String(snapshotName),
	})
	if err != nil {
		log.Printf("Couldn't create snapshot %v: %v\n", snapshotName, err)
		return nil, err
	} else {
		return output.DBClusterSnapshot, nil
	}
}



// GetClusterSnapshot gets a DB cluster snapshot.
func (clusters *DbClusters) GetClusterSnapshot(ctx context.Context, snapshotName string) (*types.DBClusterSnapshot, error) {
	output, err := clusters.AuroraClient.DescribeDBClusterSnapshots(ctx,
		&rds.DescribeDBClusterSnapshotsInput{
			DBClusterSnapshotIdentifier: aws.String(snapshotName),
		})
	if err != nil {
		log.Printf("Couldn't get snapshot %v: %v\n", snapshotName, err)
		return nil, err
	} else {
		return &output.DBClusterSnapshots[0], nil
	}
}



// CreateInstanceInCluster creates a database instance in an existing DB cluster. The first database that is
// created defaults to a read-write DB instance.
func (clusters *DbClusters) CreateInstanceInCluster(ctx context.Context, clusterName string, instanceName string,
	dbEngine string, dbInstanceClass string) (*types.DBInstance, error) {
	output, err := clusters.AuroraClient.CreateDBInstance(ctx, &rds.CreateDBInstanceInput{
		DBInstanceIdentifier: aws.String(instanceName),
		DBClusterIdentifier:  aws.String(clusterName),
		Engine:               aws.String(dbEngine),
		DBInstanceClass:      aws.String(dbInstanceClass),
	})
	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 (clusters *DbClusters) GetInstance(ctx context.Context, instanceName string) (
	*types.DBInstance, error) {
	output, err := clusters.AuroraClient.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 (clusters *DbClusters) DeleteInstance(ctx context.Context, instanceName string) error {
	_, err := clusters.AuroraClient.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 (clusters *DbClusters) GetEngineVersions(ctx context.Context, engine string, parameterGroupFamily string) (
	[]types.DBEngineVersion, error) {
	output, err := clusters.AuroraClient.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 (clusters *DbClusters) GetOrderableInstances(ctx context.Context, engine string, engineVersion string) (
	[]types.OrderableDBInstanceOption, error) {

	var output *rds.DescribeOrderableDBInstanceOptionsOutput
	var instances []types.OrderableDBInstanceOption
	var err error
	orderablePaginator := rds.NewDescribeOrderableDBInstanceOptionsPaginator(clusters.AuroraClient,
		&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 instances: %v\n", err)
			break
		} else {
			instances = append(instances, output.OrderableDBInstanceOptions...)
		}
	}
	return instances, err
}

type DbClusters struct {
	AuroraClient *rds.Client
}



// CreateDbCluster creates a DB cluster that is configured to use the specified parameter group.
// The newly created DB cluster contains a database that uses the specified engine and
// engine version.
func (clusters *DbClusters) CreateDbCluster(ctx context.Context, clusterName string, parameterGroupName string,
	dbName string, dbEngine string, dbEngineVersion string, adminName string, adminPassword string) (
	*types.DBCluster, error) {

	output, err := clusters.AuroraClient.CreateDBCluster(ctx, &rds.CreateDBClusterInput{
		DBClusterIdentifier:         aws.String(clusterName),
		Engine:                      aws.String(dbEngine),
		DBClusterParameterGroupName: aws.String(parameterGroupName),
		DatabaseName:                aws.String(dbName),
		EngineVersion:               aws.String(dbEngineVersion),
		MasterUserPassword:          aws.String(adminPassword),
		MasterUsername:              aws.String(adminName),
	})
	if err != nil {
		log.Printf("Couldn't create DB cluster %v: %v\n", clusterName, err)
		return nil, err
	} else {
		return output.DBCluster, err
	}
}

type DbClusters struct {
	AuroraClient *rds.Client
}



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

	output, err := clusters.AuroraClient.CreateDBClusterParameterGroup(ctx,
		&rds.CreateDBClusterParameterGroupInput{
			DBClusterParameterGroupName: 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.DBClusterParameterGroup, err
	}
}

type DbClusters struct {
	AuroraClient *rds.Client
}



// CreateClusterSnapshot creates a snapshot of a DB cluster.
func (clusters *DbClusters) CreateClusterSnapshot(ctx context.Context, clusterName string, snapshotName string) (
	*types.DBClusterSnapshot, error) {
	output, err := clusters.AuroraClient.CreateDBClusterSnapshot(ctx, &rds.CreateDBClusterSnapshotInput{
		DBClusterIdentifier:         aws.String(clusterName),
		DBClusterSnapshotIdentifier: aws.String(snapshotName),
	})
	if err != nil {
		log.Printf("Couldn't create snapshot %v: %v\n", snapshotName, err)
		return nil, err
	} else {
		return output.DBClusterSnapshot, nil
	}
}

type DbClusters struct {
	AuroraClient *rds.Client
}



// CreateInstanceInCluster creates a database instance in an existing DB cluster. The first database that is
// created defaults to a read-write DB instance.
func (clusters *DbClusters) CreateInstanceInCluster(ctx context.Context, clusterName string, instanceName string,
	dbEngine string, dbInstanceClass string) (*types.DBInstance, error) {
	output, err := clusters.AuroraClient.CreateDBInstance(ctx, &rds.CreateDBInstanceInput{
		DBInstanceIdentifier: aws.String(instanceName),
		DBClusterIdentifier:  aws.String(clusterName),
		Engine:               aws.String(dbEngine),
		DBInstanceClass:      aws.String(dbInstanceClass),
	})
	if err != nil {
		log.Printf("Couldn't create instance %v: %v\n", instanceName, err)
		return nil, err
	} else {
		return output.DBInstance, nil
	}
}

type DbClusters struct {
	AuroraClient *rds.Client
}



// DeleteDbCluster deletes a DB cluster without keeping a final snapshot.
func (clusters *DbClusters) DeleteDbCluster(ctx context.Context, clusterName string) error {
	_, err := clusters.AuroraClient.DeleteDBCluster(ctx, &rds.DeleteDBClusterInput{
		DBClusterIdentifier: aws.String(clusterName),
		SkipFinalSnapshot:   aws.Bool(true),
	})
	if err != nil {
		log.Printf("Couldn't delete DB cluster %v: %v\n", clusterName, err)
		return err
	} else {
		return nil
	}
}

type DbClusters struct {
	AuroraClient *rds.Client
}



// DeleteParameterGroup deletes the named DB cluster parameter group.
func (clusters *DbClusters) DeleteParameterGroup(ctx context.Context, parameterGroupName string) error {
	_, err := clusters.AuroraClient.DeleteDBClusterParameterGroup(ctx,
		&rds.DeleteDBClusterParameterGroupInput{
			DBClusterParameterGroupName: aws.String(parameterGroupName),
		})
	if err != nil {
		log.Printf("Couldn't delete parameter group %v: %v\n", parameterGroupName, err)
		return err
	} else {
		return nil
	}
}

type DbClusters struct {
	AuroraClient *rds.Client
}



// DeleteInstance deletes a DB instance.
func (clusters *DbClusters) DeleteInstance(ctx context.Context, instanceName string) error {
	_, err := clusters.AuroraClient.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
	}
}

type DbClusters struct {
	AuroraClient *rds.Client
}



// GetParameterGroup gets a DB cluster parameter group by name.
func (clusters *DbClusters) GetParameterGroup(ctx context.Context, parameterGroupName string) (
	*types.DBClusterParameterGroup, error) {
	output, err := clusters.AuroraClient.DescribeDBClusterParameterGroups(
		ctx, &rds.DescribeDBClusterParameterGroupsInput{
			DBClusterParameterGroupName: 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.DBClusterParameterGroups[0], err
	}
}

type DbClusters struct {
	AuroraClient *rds.Client
}



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

	var output *rds.DescribeDBClusterParametersOutput
	var params []types.Parameter
	var err error
	parameterPaginator := rds.NewDescribeDBClusterParametersPaginator(clusters.AuroraClient,
		&rds.DescribeDBClusterParametersInput{
			DBClusterParameterGroupName: aws.String(parameterGroupName),
			Source:                      aws.String(source),
		})
	for parameterPaginator.HasMorePages() {
		output, err = parameterPaginator.NextPage(ctx)
		if err != nil {
			log.Printf("Couldn't get paramaeters for %v: %v\n", parameterGroupName, err)
			break
		} else {
			params = append(params, output.Parameters...)
		}
	}
	return params, err
}

type DbClusters struct {
	AuroraClient *rds.Client
}



// GetClusterSnapshot gets a DB cluster snapshot.
func (clusters *DbClusters) GetClusterSnapshot(ctx context.Context, snapshotName string) (*types.DBClusterSnapshot, error) {
	output, err := clusters.AuroraClient.DescribeDBClusterSnapshots(ctx,
		&rds.DescribeDBClusterSnapshotsInput{
			DBClusterSnapshotIdentifier: aws.String(snapshotName),
		})
	if err != nil {
		log.Printf("Couldn't get snapshot %v: %v\n", snapshotName, err)
		return nil, err
	} else {
		return &output.DBClusterSnapshots[0], nil
	}
}

type DbClusters struct {
	AuroraClient *rds.Client
}



// GetDbCluster gets data about an Aurora DB cluster.
func (clusters *DbClusters) GetDbCluster(ctx context.Context, clusterName string) (*types.DBCluster, error) {
	output, err := clusters.AuroraClient.DescribeDBClusters(ctx,
		&rds.DescribeDBClustersInput{
			DBClusterIdentifier: aws.String(clusterName),
		})
	if err != nil {
		var notFoundError *types.DBClusterNotFoundFault
		if errors.As(err, &notFoundError) {
			log.Printf("DB cluster %v does not exist.\n", clusterName)
			err = nil
		} else {
			log.Printf("Couldn't get DB cluster %v: %v\n", clusterName, err)
		}
		return nil, err
	} else {
		return &output.DBClusters[0], err
	}
}

type DbClusters struct {
	AuroraClient *rds.Client
}



// GetEngineVersions gets database engine versions that are available for the specified engine
// and parameter group family.
func (clusters *DbClusters) GetEngineVersions(ctx context.Context, engine string, parameterGroupFamily string) (
	[]types.DBEngineVersion, error) {
	output, err := clusters.AuroraClient.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
	}
}

type DbClusters struct {
	AuroraClient *rds.Client
}



// GetInstance gets data about a DB instance.
func (clusters *DbClusters) GetInstance(ctx context.Context, instanceName string) (
	*types.DBInstance, error) {
	output, err := clusters.AuroraClient.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
	}
}

type DbClusters struct {
	AuroraClient *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 (clusters *DbClusters) GetOrderableInstances(ctx context.Context, engine string, engineVersion string) (
	[]types.OrderableDBInstanceOption, error) {

	var output *rds.DescribeOrderableDBInstanceOptionsOutput
	var instances []types.OrderableDBInstanceOption
	var err error
	orderablePaginator := rds.NewDescribeOrderableDBInstanceOptionsPaginator(clusters.AuroraClient,
		&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 instances: %v\n", err)
			break
		} else {
			instances = append(instances, output.OrderableDBInstanceOptions...)
		}
	}
	return instances, err
}

type DbClusters struct {
	AuroraClient *rds.Client
}



// UpdateParameters updates parameters in a named DB cluster parameter group.
func (clusters *DbClusters) UpdateParameters(ctx context.Context, parameterGroupName string, params []types.Parameter) error {
	_, err := clusters.AuroraClient.ModifyDBClusterParameterGroup(ctx,
		&rds.ModifyDBClusterParameterGroupInput{
			DBClusterParameterGroupName: 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
	}
}