Support for asynchronous lambda invocation with integration type AWS

docs/providers/aws/events/apigateway.md

@@ -483,6 +483,21 @@ functions:
               - nickname
 ```
 
+### Using asyncronous integration
+
+Use `async: true` when integrating a lambda function using event invocation. This lets API Gateway to return immediately while the lambda continues running. If not othewise speficied integration type will be `AWS`.
+
+```yml
+functions:
+  create:
+    handler: posts.create
+    events:
+      - http:
+          path: posts/create
+          method: post
+          async: true  # default is false
+```
+
 ### Catching Exceptions In Your Lambda Function
 
 In case an exception is thrown in your lambda function AWS will send an error message with `Process exited before completing request`. This will be caught by the regular expression for the 500 HTTP status and the 500 status will be returned.

lib/plugins/aws/package/compile/events/apiGateway/lib/method/index.test.js

@@ -379,6 +379,47 @@ describe('#compileMethods()', () => {
     });
   });
 
+  it('should add request parameter when async config is used', () => {
+    awsCompileApigEvents.validated.events = [
+      {
+        functionName: 'First',
+        http: {
+          path: 'users/create',
+          method: 'post',
+          async: true,
+        },
+      },
+    ];
+    return awsCompileApigEvents.compileMethods().then(() => {
+      expect(
+        awsCompileApigEvents.serverless.service.provider.compiledCloudFormationTemplate
+          .Resources.ApiGatewayMethodUsersCreatePost.Properties.Integration
+          .RequestParameters['integration.request.header.X-Amz-Invocation-Type']
+      ).to.equal("'Event'");
+    });
+  });
+
+  it('should add request parameter when integration type is AWS_PROXY and async', () => {
+    awsCompileApigEvents.validated.events = [
+      {
+        functionName: 'First',
+        http: {
+          path: 'users/create',
+          method: 'post',
+          integration: 'AWS_PROXY',
+          async: true,
+        },
+      },
+    ];
+    return awsCompileApigEvents.compileMethods().then(() => {
+      expect(
+        awsCompileApigEvents.serverless.service.provider.compiledCloudFormationTemplate
+          .Resources.ApiGatewayMethodUsersCreatePost.Properties.Integration
+          .RequestParameters['integration.request.header.X-Amz-Invocation-Type']
+      ).to.equal("'Event'");
+    });
+  });
+
   it('should set authorizer config for AWS_IAM', () => {
     awsCompileApigEvents.validated.events = [
       {

lib/plugins/aws/package/compile/events/apiGateway/lib/method/integration.js

@@ -92,9 +92,8 @@ module.exports = {
         IntegrationResponses: this.getIntegrationResponses(http),
       });
     }
-
-    if ((type === 'AWS' || type === 'HTTP' || type === 'HTTP_PROXY') &&
-      (http.request && !_.isEmpty(http.request.parameters))) {
+    if (((type === 'AWS' || type === 'HTTP' || type === 'HTTP_PROXY') &&
+      (http.request && !_.isEmpty(http.request.parameters))) || http.async) {
       _.assign(integration, {
         RequestParameters: this.getIntegrationRequestParameters(http),
       });
@@ -192,6 +191,11 @@ module.exports = {
         parameters[`integration.${key.substring('method.'.length)}`] = key;
       });
     }
+
+    if (http.async) {
+      parameters['integration.request.header.X-Amz-Invocation-Type'] = "'Event'";
+    }
+
     return parameters;
   },
 

lib/plugins/aws/package/compile/events/apiGateway/lib/validate.js

@@ -385,6 +385,11 @@ module.exports = {
       }
       return normalizedIntegration;
     }
+
+    if (http.async) {
+      return 'AWS';
+    }
+
     return 'AWS_PROXY';
   },
 

lib/plugins/aws/package/compile/events/apiGateway/lib/validate.test.js

@@ -1563,6 +1563,27 @@ describe('#validate()', () => {
     expect(validated.events[0].http.integration).to.equal('MOCK');
   });
 
+  it('should support async AWS integration', () => {
+    awsCompileApigEvents.serverless.service.functions = {
+      first: {
+        events: [
+          {
+            http: {
+              method: 'GET',
+              path: 'users/list',
+              async: true,
+            },
+          },
+        ],
+      },
+    };
+
+    const validated = awsCompileApigEvents.validate();
+    expect(validated.events).to.be.an('Array').with.length(1);
+    expect(validated.events[0].http.integration).to.equal('AWS');
+    expect(validated.events[0].http.async);
+  });
+
   it('should show a warning message when using request / response config with LAMBDA-PROXY', () => {
     awsCompileApigEvents.serverless.service.functions = {
       first: {