Add Application Load Balancer event source

docs/providers/aws/README.md

@@ -93,6 +93,7 @@ If you have any questions, [search the forums](https://forum.serverless.com?utm_
         <li><a href="./events/schedule.md">Schedule</a></li>
         <li><a href="./events/sns.md">SNS</a></li>
         <li><a href="./events/sqs.md">SQS</a></li>
+        <li><a href="./evetns/alb.md">ALB</a></li>
         <li><a href="./events/alexa-skill.md">Alexa Skill</a></li>
         <li><a href="./events/alexa-smart-home.md">Alexa Smart Home</a></li>
         <li><a href="./events/iot.md">IoT</a></li>

docs/providers/aws/events/alb.md

@@ -0,0 +1,32 @@
+<!--
+title: Serverless Framework - AWS Lambda Events - ALB
+menuText: Application Load Balancer
+menuOrder: 8
+description: Setting up AWS Application Load Balancer events with AWS Lambda via the Serverless Framework
+layout: Doc
+-->
+
+<!-- DOCS-SITE-LINK:START automatically generated  -->
+### [Read this on the main serverless docs site](https://www.serverless.com/framework/docs/providers/aws/events/alb)
+<!-- DOCS-SITE-LINK:END -->
+
+# Application Load Balancer
+
+[Application Load Balancers](https://docs.aws.amazon.com/elasticloadbalancing/latest/application/introduction.html) can be used to re-route requests when certain traffic patterns are met. While traffic can be routed to services such as EC2 it [can also be routed to Lambda functions](https://aws.amazon.com/de/blogs/networking-and-content-delivery/lambda-functions-as-targets-for-application-load-balancers/) which can in turn be used process incoming requests.
+
+The Serverless Framework makes it possible to setup the connection between Application Load Balancers and Lamdba functions with the help of the `alb` event.
+
+## Event definition
+
+```yml
+functions:
+  albEventConsumer:
+    handler: handler.hello
+    events:
+      - alb:
+          listenerArn: arn:aws:elasticloadbalancing:us-east-1:12345:listener/app/my-load-balancer/50dc6c495c0c9188/
+          priority: 1
+          conditions:
+            host: example.com
+            path: /hello
+```

docs/providers/aws/events/alexa-skill.md

@@ -1,7 +1,7 @@
 <!--
 title: Serverless Framework - AWS Lambda Events - Alexa Skill
 menuText: Alexa Skill
-menuOrder: 8
+menuOrder: 9
 description:  Setting up AWS Alexa Skill Events with AWS Lambda via the Serverless Framework
 layout: Doc
 -->

docs/providers/aws/events/alexa-smart-home.md

@@ -1,7 +1,7 @@
 <!--
 title: Serverless Framework - AWS Lambda Events - Alexa Smart Home
 menuText: Alexa Smart Home
-menuOrder: 13
+menuOrder: 10
 description:  Setting up AWS Alexa Smart Home Events with AWS Lambda via the Serverless Framework
 layout: Doc
 -->

docs/providers/aws/events/cloudwatch-event.md

@@ -1,7 +1,7 @@
 <!--
 title: Serverless Framework - AWS Lambda Events - CloudWatch Event
 menuText: CloudWatch Event
-menuOrder: 10
+menuOrder: 12
 description:  Setting up AWS CloudWatch Events with AWS Lambda via the Serverless Framework
 layout: Doc
 -->

docs/providers/aws/events/cloudwatch-log.md

@@ -1,7 +1,7 @@
 <!--
 title: Serverless Framework - AWS Lambda Events - CloudWatch Log
 menuText: CloudWatch Log
-menuOrder: 11
+menuOrder: 13
 description:  Setting up AWS CloudWatch Logs with AWS Lambda via the Serverless Framework
 layout: Doc
 -->

docs/providers/aws/events/cognito-user-pool.md

@@ -1,7 +1,7 @@
 <!--
 title: Serverless Framework - AWS Lambda Events - Cognito User Pool
 menuText: Cognito User Pool
-menuOrder: 12
+menuOrder: 14
 description:  Setting up AWS Cognito User Pool Triggers with AWS Lambda via the Serverless Framework
 layout: Doc
 -->

docs/providers/aws/events/iot.md

@@ -1,7 +1,7 @@
 <!--
 title: Serverless Framework - AWS Lambda Events - IoT
 menuText: IoT
-menuOrder: 9
+menuOrder: 11
 description:  Setting up AWS IoT Events with AWS Lambda via the Serverless Framework
 layout: Doc
 -->

docs/providers/aws/guide/serverless.yml.md

@@ -269,6 +269,12 @@ functions:
       - cognitoUserPool:
           pool: MyUserPool
           trigger: PreSignUp
+      - alb:
+          listenerArn: arn:aws:elasticloadbalancing:us-east-1:12345:listener/app/my-load-balancer/50dc6c495c0c9188/
+          priority: 1
+          conditions:
+            host: example.com
+            path: /hello
 
 layers:
   hello: # A Lambda layer

lib/plugins/Plugins.json

@@ -38,6 +38,7 @@
     "./aws/package/compile/events/websockets/index.js",
     "./aws/package/compile/events/sns/index.js",
     "./aws/package/compile/events/stream/index.js",
+    "./aws/package/compile/events/alb/index.js",
     "./aws/package/compile/events/alexaSkill/index.js",
     "./aws/package/compile/events/alexaSmartHome/index.js",
     "./aws/package/compile/events/iot/index.js",

lib/plugins/aws/lib/naming.js

@@ -369,6 +369,14 @@ module.exports = {
     }`;
   },
 
+  // ALB
+  getAlbTargetGroupLogicalId(functionName) {
+    return `${this.getNormalizedFunctionName(functionName)}AlbTargetGroup`;
+  },
+  getAlbListenerRuleLogicalId(functionName, idx) {
+    return `${this.getNormalizedFunctionName(functionName)}AlbListenerRule${idx}`;
+  },
+
   // Permissions
   getLambdaS3PermissionLogicalId(functionName, bucketName) {
     return `${this.getNormalizedFunctionName(functionName)}LambdaPermission${this
@@ -411,4 +419,7 @@ module.exports = {
       .getNormalizedFunctionName(functionName)}LambdaPermissionCognitoUserPool${
       this.normalizeNameToAlphaNumericOnly(poolId)}TriggerSource${triggerSource}`;
   },
+  getLambdaAlbPermissionLogicalId(functionName) {
+    return `${this.getNormalizedFunctionName(functionName)}LambdaPermissionAlb`;
+  },
 };

lib/plugins/aws/lib/naming.test.js

@@ -674,6 +674,13 @@ describe('#naming()', () => {
         'CustomMessage'
       )).to.equal('FunctionNameLambdaPermissionCognitoUserPoolPool1TriggerSourceCustomMessage');
     });
+
+    describe('#getLambdaAlbPermissionLogicalId()', () => {
+      it('should normalize the function name', () => {
+        expect(sdk.naming.getLambdaAlbPermissionLogicalId('functionName'))
+          .to.equal('FunctionNameLambdaPermissionAlb');
+      });
+    });
   });
 
   describe('#getQueueLogicalId()', () => {
@@ -682,4 +689,18 @@ describe('#naming()', () => {
         .to.equal('FunctionNameEventSourceMappingSQSMyQueue');
     });
   });
+
+  describe('#getAlbTargetGroupLogicalId()', () => {
+    it('should normalize the function name', () => {
+      expect(sdk.naming.getAlbTargetGroupLogicalId('functionName'))
+        .to.equal('FunctionNameAlbTargetGroup');
+    });
+  });
+
+  describe('#getAlbListenerRuleLogicalId()', () => {
+    it('should normalize the function name and add an index', () => {
+      expect(sdk.naming.getAlbListenerRuleLogicalId('functionName', 0))
+        .to.equal('FunctionNameAlbListenerRule0');
+    });
+  });
 });

lib/plugins/aws/package/compile/events/alb/index.js

@@ -0,0 +1,39 @@
+'use strict';
+
+const BbPromise = require('bluebird');
+
+const validate = require('./lib/validate');
+const compileTargetGroups = require('./lib/targetGroups');
+const compileListenerRules = require('./lib/listenerRules');
+const compilePermissions = require('./lib/permissions');
+
+class AwsCompileAlbEvents {
+  constructor(serverless, options) {
+    this.serverless = serverless;
+    this.options = options;
+    this.provider = this.serverless.getProvider('aws');
+
+    Object.assign(
+      this,
+      validate,
+      compileTargetGroups,
+      compileListenerRules,
+      compilePermissions
+    );
+
+    this.hooks = {
+      'package:compileEvents': () => {
+        return BbPromise.try(() => {
+          this.validated = this.validate();
+          if (this.validated.events.length === 0) return;
+
+          this.compileTargetGroups();
+          this.compileListenerRules();
+          this.compilePermissions();
+        });
+      },
+    };
+  }
+}
+
+module.exports = AwsCompileAlbEvents;

lib/plugins/aws/package/compile/events/alb/index.test.js

@@ -0,0 +1,83 @@
+'use strict';
+
+const expect = require('chai').expect;
+const sinon = require('sinon');
+const AwsProvider = require('../../../../provider/awsProvider');
+const AwsCompileAlbEvents = require('./index');
+const Serverless = require('../../../../../../Serverless');
+
+describe('AwsCompileAlbEvents', () => {
+  let awsCompileAlbEvents;
+
+  beforeEach(() => {
+    const serverless = new Serverless();
+    const options = {
+      stage: 'dev',
+      region: 'us-east-1',
+    };
+    serverless.setProvider('aws', new AwsProvider(serverless, options));
+    awsCompileAlbEvents = new AwsCompileAlbEvents(serverless, options);
+  });
+
+  describe('#constructor()', () => {
+    let compileTargetGroupsStub;
+    let compileListenerRulesStub;
+    let compilePermissionsStub;
+
+    beforeEach(() => {
+      compileTargetGroupsStub = sinon
+        .stub(awsCompileAlbEvents, 'compileTargetGroups').resolves();
+      compileListenerRulesStub = sinon
+        .stub(awsCompileAlbEvents, 'compileListenerRules').resolves();
+      compilePermissionsStub = sinon
+        .stub(awsCompileAlbEvents, 'compilePermissions').resolves();
+    });
+
+    afterEach(() => {
+      awsCompileAlbEvents.compileTargetGroups.restore();
+      awsCompileAlbEvents.compileListenerRules.restore();
+      awsCompileAlbEvents.compilePermissions.restore();
+    });
+
+    it('should have hooks', () => expect(awsCompileAlbEvents.hooks).to.be.not.empty);
+
+    it('should set the provider variable to be an instanceof AwsProvider', () =>
+      expect(awsCompileAlbEvents.provider).to.be.instanceof(AwsProvider));
+
+    describe('"package:compileEvents" promise chain', () => {
+      afterEach(() => {
+        awsCompileAlbEvents.validate.restore();
+      });
+
+      it('should run the promise chain in order', () => {
+        const validateStub = sinon
+          .stub(awsCompileAlbEvents, 'validate').returns({
+            events: [{
+              functionName: 'first',
+              listenerArn: 'arn:aws:elasticloadbalancing:'
+                + 'us-east-1:123456789012:listener/app/my-load-balancer/'
+                + '50dc6c495c0c9188/f2f7dc8efc522ab2',
+              priority: 1,
+              conditions: {
+                host: 'example.com',
+                path: '/hello',
+              },
+            }],
+          });
+
+        return awsCompileAlbEvents.hooks['package:compileEvents']().then(() => {
+          expect(validateStub.calledOnce).to.be.equal(true);
+          expect(compileTargetGroupsStub.calledAfter(validateStub)).to.be.equal(true);
+          expect(compileListenerRulesStub.calledAfter(compileTargetGroupsStub)).to.be.equal(true);
+          expect(compilePermissionsStub.calledAfter(compileListenerRulesStub)).to.be.equal(true);
+        });
+      });
+    });
+
+    it('should resolve if no functions are given', () => {
+      awsCompileAlbEvents.serverless.service.functions = {};
+
+      return awsCompileAlbEvents.hooks['package:compileEvents']();
+    });
+  });
+});

lib/plugins/aws/package/compile/events/alb/lib/listenerRules.js

@@ -0,0 +1,44 @@
+'use strict';
+
+module.exports = {
+  compileListenerRules() {
+    this.validated.events.forEach((event) => {
+      const listenerRuleLogicalId = this.provider.naming
+        .getAlbListenerRuleLogicalId(event.functionName, event.priority);
+      const targetGroupLogicalId = this.provider.naming
+        .getAlbTargetGroupLogicalId(event.functionName);
+
+      const Conditions = [
+        {
+          Field: 'path-pattern',
+          Values: [event.conditions.path],
+        },
+      ];
+      if (event.conditions.host) {
+        Conditions.push({
+          Field: 'host-header',
+          Values: [event.conditions.host],
+        });
+      }
+
+      Object.assign(this.serverless.service.provider.compiledCloudFormationTemplate.Resources, {
+        [listenerRuleLogicalId]: {
+          Type: 'AWS::ElasticLoadBalancingV2::ListenerRule',
+          Properties: {
+            Actions: [
+              {
+                Type: 'forward',
+                TargetGroupArn: {
+                  Ref: targetGroupLogicalId,
+                },
+              },
+            ],
+            Conditions,
+            ListenerArn: event.listenerArn,
+            Priority: event.priority,
+          },
+        },
+      });
+    });
+  },
+};