packages/aws-cdk-lib/aws-apigatewayv2-integrations/lib/http/sqs.ts

import { IConstruct } from 'constructs';
import * as apigwv2 from '../../../aws-apigatewayv2';
import * as iam from '../../../aws-iam';
import * as sqs from '../../../aws-sqs';
import { ValidationError } from '../../../core';

/**
 * Properties to initialize `HttpSqsIntegration`.
 */
export interface HttpSqsIntegrationProps {
  /**
   * Specifies how to transform HTTP requests before sending them to the backend.
   *
   * @see https://docs.aws.amazon.com/apigateway/latest/developerguide/http-api-develop-integrations-aws-services.html#http-api-develop-integrations-aws-services-parameter-mapping
   * @see https://docs.aws.amazon.com/apigateway/latest/developerguide/http-api-develop-integrations-aws-services-reference.html
   *
   * @default - specify `QueueUrl`. Additionally, set `MessageBody` to `$request.body.MessageBody` for `SQS_SEND_MESSAGE` subtype
   * and set `ReceiptHandle` to `$request.body.ReceiptHandle` for `SQS_DELETE_MESSAGE` subtype.
   */
  readonly parameterMapping?: apigwv2.ParameterMapping;

  /**
   * The subtype of the HTTP integration.
   *
   * Only subtypes starting with SQS_ can be specified.
   *
   * @default HttpIntegrationSubtype.SQS_SEND_MESSAGE
   */
  readonly subtype?: apigwv2.HttpIntegrationSubtype;

  /**
   * SQS queue that Integrates with API Gateway
   */
  readonly queue: sqs.IQueue;
}

/**
 * The Sqs integration resource for HTTP API
 */
export class HttpSqsIntegration extends apigwv2.HttpRouteIntegration {
  private readonly subtype: apigwv2.HttpIntegrationSubtype;
  /**
   * @param id id of the underlying integration construct
   * @param props properties to configure the integration
   */
  constructor(
    id: string,
    private readonly props: HttpSqsIntegrationProps,
  ) {
    super(id);
    this.subtype = this.props.subtype ?? apigwv2.HttpIntegrationSubtype.SQS_SEND_MESSAGE;
  }

  public bind(options: apigwv2.HttpRouteIntegrationBindOptions): apigwv2.HttpRouteIntegrationConfig {
    if (this.props.subtype && !this.props.subtype.startsWith('SQS-')) {
      throw new ValidationError('Subtype must start with `SQS_`', options.scope);
    }

    const invokeRole = new iam.Role(options.scope, 'InvokeRole', {
      assumedBy: new iam.ServicePrincipal('apigateway.amazonaws.com'),
    });

    invokeRole.addToPolicy(
      new iam.PolicyStatement({
        effect: iam.Effect.ALLOW,
        sid: 'AllowSqsExecution',
        actions: [this.determineActionBySubtype(options.scope)],
        resources: [this.props.queue.queueArn],
      }),
    );

    return {
      payloadFormatVersion: apigwv2.PayloadFormatVersion.VERSION_1_0,
      type: apigwv2.HttpIntegrationType.AWS_PROXY,
      subtype: this.props.subtype ?? apigwv2.HttpIntegrationSubtype.SQS_SEND_MESSAGE,
      credentials: apigwv2.IntegrationCredentials.fromRole(invokeRole),
      connectionType: apigwv2.HttpConnectionType.INTERNET,
      parameterMapping: this.props.parameterMapping ?? this.createDefaultParameterMapping(options.scope),
    };
  }

  private determineActionBySubtype(scope: IConstruct): string {
    switch (this.subtype) {
      case apigwv2.HttpIntegrationSubtype.SQS_SEND_MESSAGE:
        return 'sqs:SendMessage';
      case apigwv2.HttpIntegrationSubtype.SQS_RECEIVE_MESSAGE:
        return 'sqs:ReceiveMessage';
      case apigwv2.HttpIntegrationSubtype.SQS_DELETE_MESSAGE:
        return 'sqs:DeleteMessage';
      case apigwv2.HttpIntegrationSubtype.SQS_PURGE_QUEUE:
        return 'sqs:PurgeQueue';
      default:
        throw new ValidationError(`Unsupported subtype: ${this.subtype}`, scope);
    }
  }

  private createDefaultParameterMapping(scope: IConstruct): apigwv2.ParameterMapping {
    switch (this.subtype) {
      case apigwv2.HttpIntegrationSubtype.SQS_SEND_MESSAGE:
        return new apigwv2.ParameterMapping()
          .custom('QueueUrl', this.props.queue.queueUrl)
          .custom('MessageBody', '$request.body.MessageBody');
      case apigwv2.HttpIntegrationSubtype.SQS_RECEIVE_MESSAGE:
        return new apigwv2.ParameterMapping()
          .custom('QueueUrl', this.props.queue.queueUrl);
      case apigwv2.HttpIntegrationSubtype.SQS_DELETE_MESSAGE:
        return new apigwv2.ParameterMapping()
          .custom('QueueUrl', this.props.queue.queueUrl)
          .custom('ReceiptHandle', '$request.body.ReceiptHandle');
      case apigwv2.HttpIntegrationSubtype.SQS_PURGE_QUEUE:
        return new apigwv2.ParameterMapping()
          .custom('QueueUrl', this.props.queue.queueUrl);
      default:
        throw new ValidationError(`Unsupported subtype: ${this.subtype}`, scope);
    }
  }
}