Supporting SNS events

README.md

@@ -74,7 +74,7 @@ The plugin relies on the [AWS Lambda traffic shifting feature](https://docs.aws.
 
 ## Limitations
 
-For now, the plugin only works with Lambda functions invoked by API Gateway or Stream based events (such as the triggered by Kinesis or DynamoDB Streams). More events will be added soon.
+For now, the plugin only works with Lambda functions invoked by API Gateway, Stream based (such as the triggered by Kinesis or DynamoDB Streams) and SNS based events. More events will be added soon.
 
 ## License
 

example/package.json

@@ -10,12 +10,12 @@
  "devDependencies": {
  "serverless": "^1.26.1",
  "serverless-plugin-aws-alerts": "^1.2.4",
- "serverless-plugin-canary-deployments": "^0.1.0"
+ "serverless-plugin-canary-deployments": "^0.2.0"
  },
  "scripts": {
  "test": "echo \"Error: no test specified\" && exit 1",
- "package": "npm un --no-save serverless-plugin-canary-deployments && npm pack ../ && npm i --no-save serverless-plugin-canary-deployments-0.1.0.tgz && sls package -s dev",
- "deploy": "npm un --no-save serverless-plugin-canary-deployments && npm pack ../ && npm i --no-save serverless-plugin-canary-deployments-0.1.0.tgz && sls deploy -s dev",
+ "package": "npm un --no-save serverless-plugin-canary-deployments && npm pack ../ && npm i --no-save serverless-plugin-canary-deployments-0.2.0.tgz && sls package -s dev",
+ "deploy": "npm un --no-save serverless-plugin-canary-deployments && npm pack ../ && npm i --no-save serverless-plugin-canary-deployments-0.2.0.tgz && sls deploy -s dev",
  "populate-table": "node ./scripts/populate-test-table"
  },
  "author": "",

example/serverless.yml

@@ -28,6 +28,7 @@ functions:
  Fn::GetAtt:
  - StreamsTestTable
  - StreamArn
+ - sns: snsTopic
  alarms:
  - name: foo
  namespace: 'AWS/Lambda'

fixtures/1.input.json

@@ -353,6 +353,54 @@
  }
  }
  },
+ "SNSTopicSnsTopic": {
+ "Type": "AWS::SNS::Topic",
+ "Properties": {
+ "TopicName": "snsTopic",
+ "DisplayName": "",
+ "Subscription": [
+ {
+ "Endpoint": {
+ "Fn::GetAtt": [
+ "HelloLambdaFunction",
+ "Arn"
+ ]
+ },
+ "Protocol": "lambda"
+ }
+ ]
+ }
+ },
+ "HelloLambdaPermissionSnsTopicSNS": {
+ "Type": "AWS::Lambda::Permission",
+ "Properties": {
+ "FunctionName": {
+ "Fn::GetAtt": [
+ "HelloLambdaFunction",
+ "Arn"
+ ]
+ },
+ "Action": "lambda:InvokeFunction",
+ "Principal": "sns.amazonaws.com",
+ "SourceArn": {
+ "Fn::Join": [
+ "",
+ [
+ "arn:aws:sns:",
+ {
+ "Ref": "AWS::Region"
+ },
+ ":",
+ {
+ "Ref": "AWS::AccountId"
+ },
+ ":",
+ "snsTopic"
+ ]
+ ]
+ }
+ }
+ },
  "HelloEventSourceMappingDynamodbStreamsTestTable": {
  "Type": "AWS::Lambda::EventSourceMapping",
  "DependsOn": "IamRoleLambdaExecution",
@@ -464,4 +512,4 @@
  }
  }
  }
-}
+}

fixtures/1.output.json

@@ -334,6 +334,48 @@
  }
  }
  },
+ "SNSTopicSnsTopic": {
+ "Type": "AWS::SNS::Topic",
+ "Properties": {
+ "TopicName": "snsTopic",
+ "DisplayName": "",
+ "Subscription": [
+ {
+ "Endpoint": {
+ "Ref": "HelloLambdaFunctionAliasLive"
+ },
+ "Protocol": "lambda"
+ }
+ ]
+ }
+ },
+ "HelloLambdaPermissionSnsTopicSNS": {
+ "Type": "AWS::Lambda::Permission",
+ "Properties": {
+ "FunctionName": {
+ "Ref": "HelloLambdaFunctionAliasLive"
+ },
+ "Action": "lambda:InvokeFunction",
+ "Principal": "sns.amazonaws.com",
+ "SourceArn": {
+ "Fn::Join": [
+ "",
+ [
+ "arn:aws:sns:",
+ {
+ "Ref": "AWS::Region"
+ },
+ ":",
+ {
+ "Ref": "AWS::AccountId"
+ },
+ ":",
+ "snsTopic"
+ ]
+ ]
+ }
+ }
+ },
  "HelloEventSourceMappingDynamodbStreamsTestTable": {
  "Type": "AWS::Lambda::EventSourceMapping",
  "DependsOn": "IamRoleLambdaExecution",
@@ -376,6 +418,31 @@
  "Statistic": "Minimum"
  }
  },
+ "StreamsTestTable": {
+ "Type": "AWS::DynamoDB::Table",
+ "Properties": {
+ "TableName": "StreamsTestTable",
+ "AttributeDefinitions": [
+ {
+ "AttributeName": "id",
+ "AttributeType": "S"
+ }
+ ],
+ "KeySchema": [
+ {
+ "AttributeName": "id",
+ "KeyType": "HASH"
+ }
+ ],
+ "ProvisionedThroughput": {
+ "ReadCapacityUnits": 1,
+ "WriteCapacityUnits": 1
+ },
+ "StreamSpecification": {
+ "StreamViewType": "NEW_AND_OLD_IMAGES"
+ }
+ }
+ },
  "CanarydeploymentstestdevDeploymentApplication": {
  "Type": "AWS::CodeDeploy::Application",
  "Properties": {
@@ -481,31 +548,6 @@
  }
  }
  }
- },
- "StreamsTestTable": {
- "Type": "AWS::DynamoDB::Table",
- "Properties": {
- "TableName": "StreamsTestTable",
- "AttributeDefinitions": [
- {
- "AttributeName": "id",
- "AttributeType": "S"
- }
- ],
- "KeySchema": [
- {
- "AttributeName": "id",
- "KeyType": "HASH"
- }
- ],
- "ProvisionedThroughput": {
- "ReadCapacityUnits": 1,
- "WriteCapacityUnits": 1
- },
- "StreamSpecification": {
- "StreamViewType": "NEW_AND_OLD_IMAGES"
- }
- }
  }
  },
  "Outputs": {
@@ -548,4 +590,4 @@
  }
  }
  }
-}
+}

fixtures/1.service.json

@@ -17,6 +17,9 @@
  ]
  }
  }
+ },
+ {
+ "sns": "snsTopic"
  }
  ],
  "deploymentSettings": {

lib/CfTemplateGenerators/Sns.js

@@ -0,0 +1,23 @@
+function replaceTopicSubscriptionFunctionWithAlias(snsTopic, functionAlias, functionName) {
+ const subscriptions = snsTopic.Properties.Subscription;
+
+ const isTargetSubscription = (subscription) => {
+ const endpoint = subscription.Endpoint || {};
+ const funcDetails = (endpoint['Fn::GetAtt'] || []);
+ const [funcName] = funcDetails;
+ return funcName ? funcName === functionName : false;
+ };
+
+ const restOfSubscriptions = subscriptions.filter(subscription => !isTargetSubscription(subscription));
+ const subscriptionWithAlias = { Endpoint: { Ref: functionAlias }, Protocol: 'lambda' };
+ const newSubscriptions = [...restOfSubscriptions, subscriptionWithAlias];
+
+ const newProperties = { ...snsTopic.Properties, Subscription: newSubscriptions };
+ return { ...snsTopic, Properties: newProperties };
+}
+
+const Sns = {
+ replaceTopicSubscriptionFunctionWithAlias
+};
+
+module.exports = Sns;

lib/CfTemplateGenerators/Sns.test.js

@@ -0,0 +1,54 @@
+const { expect } = require('chai');
+const Sns = require('./Sns');
+
+describe('Sns', () => {
+ describe('.replaceTopicSubscriptionFunctionWithAlias', () => {
+ const functionName = 'HelloLambdaFunction';
+ const snsTopic = {
+ Type: 'AWS::SNS::Topic',
+ Properties: {
+ TopicName: 'snsTopic',
+ DisplayName: '',
+ Subscription: [
+ {
+ Endpoint: {
+ 'Fn::GetAtt': [functionName, 'Arn']
+ },
+ Protocol: 'lambda'
+ },
+ {
+ Endpoint: {
+ 'Fn::GetAtt': ['func', 'Arn']
+ },
+ Protocol: 'lambda'
+ }
+ ]
+ }
+ };
+
+ it("replaces the topic subscription's function for an alias", () => {
+ const functionAlias = 'TheFunctionAlias';
+ const expected = {
+ Type: 'AWS::SNS::Topic',
+ Properties: {
+ TopicName: 'snsTopic',
+ DisplayName: '',
+ Subscription: [
+ {
+ Endpoint: {
+ 'Fn::GetAtt': ['func', 'Arn']
+ },
+ Protocol: 'lambda'
+ },
+ {
+ Endpoint: { Ref: functionAlias },
+ Protocol: 'lambda'
+ }
+ ]
+ }
+ };
+ const actual = Sns.replaceTopicSubscriptionFunctionWithAlias(snsTopic, functionAlias, functionName);
+ expect(actual).to.deep.equal(expected);
+ });
+ });
+});

lib/CfTemplateGenerators/index.js

@@ -2,8 +2,10 @@ const CodeDeploy = require('./CodeDeploy');
 const Iam = require('./Iam');
 const Lambda = require('./Lambda');
 const ApiGateway = require('./ApiGateway');
+const Sns = require('./Sns');
 
 module.exports.codeDeploy = CodeDeploy;
 module.exports.iam = Iam;
 module.exports.lambda = Lambda;
 module.exports.apiGateway = ApiGateway;
+module.exports.sns = Sns;