doc_usercustomresource_test.go

package sparta

import (
	"context"

	"github.com/aws/aws-lambda-go/lambdacontext"
	gof "github.com/awslabs/goformation/v5/cloudformation"
	goflambda "github.com/awslabs/goformation/v5/cloudformation/lambda"
	spartaCFResources "github.com/mweagle/Sparta/v3/aws/cloudformation/resources"
	"github.com/rs/zerolog"
)

// Standard AWS λ function
func helloWorld(ctx context.Context,
	props map[string]interface{}) (string, error) {
	lambdaCtx, _ := lambdacontext.FromContext(ctx)
	Logger().Info().
		Str("RequestID", lambdaCtx.AwsRequestID).
		Interface("Properties", props).
		Msg("Lambda event")
	return "Event processed", nil
}

// User defined λ-backed CloudFormation CustomResource
func userDefinedCustomResource(ctx context.Context,
	event spartaCFResources.CloudFormationLambdaEvent) (map[string]interface{}, error) {

	logger, _ := ctx.Value(ContextKeyLogger).(*zerolog.Logger)
	lambdaCtx, _ := lambdacontext.FromContext(ctx)

	var opResults = map[string]interface{}{
		"CustomResourceResult": "Victory!",
	}

	opErr := spartaCFResources.SendCloudFormationResponse(lambdaCtx,
		&event,
		opResults,
		nil,
		logger)
	return opResults, opErr
}

func ExampleLambdaAWSInfo_RequireCustomResource() {

	lambdaFn, _ := NewAWSLambda(LambdaName(helloWorld),
		helloWorld,
		IAMRoleDefinition{})

	cfResName, _ := lambdaFn.RequireCustomResource(IAMRoleDefinition{},
		userDefinedCustomResource,
		nil,
		nil)

	lambdaFn.Decorator = func(ctx context.Context,
		serviceName string,
		lambdaResourceName string,
		lambdaResource *goflambda.Function,
		resourceMetadata map[string]interface{},
		lambdaFunctionCode *goflambda.Function_Code,
		buildID string,
		template *gof.Template,
		logger *zerolog.Logger) (context.Context, error) {

		// Pass CustomResource outputs to the λ function
		resourceMetadata["CustomResource"] = gof.GetAtt(cfResName, "CustomResourceResult")
		return ctx, nil
	}

	var lambdaFunctions []*LambdaAWSInfo
	lambdaFunctions = append(lambdaFunctions, lambdaFn)

	mainErr := Main("SpartaUserCustomResource",
		"Uses a user-defined CloudFormation CustomResource",
		lambdaFunctions,
		nil,
		nil)
	if mainErr != nil {
		panic("Failed to invoke sparta.Main: %s" + mainErr.Error())
	}
}