Merge pull request #151 from iwaiktos/add-cloudwatchevent

Add support for CloudWatch Events

Author: horike37

lib/deploy/events/cloudWatchEvent/compileCloudWatchEventEvents.js

@@ -0,0 +1,156 @@
+'use strict';
+
+const _ = require('lodash');
+const BbPromise = require('bluebird');
+
+module.exports = {
+  compileCloudWatchEventEvents() {
+    _.forEach(this.getAllStateMachines(), (stateMachineName) => {
+      const stateMachineObj = this.getStateMachine(stateMachineName);
+      let cloudWatchEventNumberInFunction = 0;
+
+      if (stateMachineObj.events) {
+        _.forEach(stateMachineObj.events, (event) => {
+          if (event.cloudwatchEvent) {
+            cloudWatchEventNumberInFunction++;
+            let EventPattern;
+            let State;
+            let Input;
+            let InputPath;
+            let Description;
+            let Name;
+
+            if (typeof event.cloudwatchEvent === 'object') {
+              if (!event.cloudwatchEvent.event) {
+                const errorMessage = [
+                  `Missing "event" property for cloudwatch event in stateMachine ${stateMachineName}`, // eslint-disable-line max-len
+                  ' Please check the docs for more info.',
+                ].join('');
+                throw new this.serverless.classes
+                  .Error(errorMessage);
+              }
+
+              EventPattern = JSON.stringify(event.cloudwatchEvent.event);
+              State = 'ENABLED';
+              if (event.cloudwatchEvent.enabled === false) {
+                State = 'DISABLED';
+              }
+              Input = event.cloudwatchEvent.input;
+              InputPath = event.cloudwatchEvent.inputPath;
+              Description = event.cloudwatchEvent.description;
+              Name = event.cloudwatchEvent.name;
+
+              if (Input && InputPath) {
+                const errorMessage = [
+                  'You can\'t set both input & inputPath properties at the',
+                  'same time for cloudwatch events.',
+                  'Please check the AWS docs for more info',
+                ].join('');
+                throw new this.serverless.classes.Error(errorMessage);
+              }
+
+              if (Input && typeof Input === 'object') {
+                Input = JSON.stringify(Input);
+              }
+              if (Input && typeof Input === 'string') {
+                // escape quotes to favor JSON.parse
+                Input = Input.replace(/\"/g, '\\"'); // eslint-disable-line
+              }
+            } else {
+              const errorMessage = [
+                `CloudWatch event of stateMachine "${stateMachineName}" is not an object`,
+                ' Please check the docs for more info.',
+              ].join('');
+              throw new this.serverless.classes
+                .Error(errorMessage);
+            }
+
+            const stateMachineLogicalId = this
+              .getStateMachineLogicalId(stateMachineName, stateMachineObj);
+            const cloudWatchLogicalId = this
+              .getCloudWatchEventLogicalId(stateMachineName, cloudWatchEventNumberInFunction);
+            const cloudWatchIamRoleLogicalId = this
+              .getCloudWatchEventToStepFunctionsIamRoleLogicalId(stateMachineName);
+            const cloudWatchId = this.getCloudWatchEventId(stateMachineName);
+            const policyName = this.getCloudWatchEventPolicyName(stateMachineName);
+
+            const cloudWatchEventRuleTemplate = `
+              {
+                "Type": "AWS::Events::Rule",
+                "Properties": {
+                  "EventPattern": ${EventPattern.replace(/\\n|\\r/g, '')},
+                  "State": "${State}",
+                  ${Description ? `"Description": "${Description}",` : ''}
+                  ${Name ? `"Name": "${Name}",` : ''}
+                  "Targets": [{
+                    ${Input ? `"Input": "${Input.replace(/\\n|\\r/g, '')}",` : ''}
+                    ${InputPath ? `"InputPath": "${InputPath.replace(/\r?\n/g, '')}",` : ''}
+                    "Arn": { "Ref": "${stateMachineLogicalId}" },
+                    "Id": "${cloudWatchId}",
+                    "RoleArn": {
+                      "Fn::GetAtt": [
+                        "${cloudWatchIamRoleLogicalId}",
+                        "Arn"
+                      ]
+                    }
+                  }]
+                }
+              }
+            `;
+
+            const iamRoleTemplate = `
+            {
+              "Type": "AWS::IAM::Role",
+              "Properties": {
+                "AssumeRolePolicyDocument": {
+                  "Version": "2012-10-17",
+                  "Statement": [
+                    {
+                      "Effect": "Allow",
+                      "Principal": {
+                        "Service": "events.amazonaws.com"
+                      },
+                      "Action": "sts:AssumeRole"
+                    }
+                  ]
+                },
+                "Policies": [
+                  {
+                    "PolicyName": "${policyName}",
+                    "PolicyDocument": {
+                      "Version": "2012-10-17",
+                      "Statement": [
+                        {
+                          "Effect": "Allow",
+                          "Action": [
+                            "states:StartExecution"
+                          ],
+                          "Resource": {
+                            "Ref": "${stateMachineLogicalId}"
+                          }
+                        }
+                      ]
+                    }
+                  }
+                ]
+              }
+            }
+            `;
+
+            const newCloudWatchEventRuleObject = {
+              [cloudWatchLogicalId]: JSON.parse(cloudWatchEventRuleTemplate),
+            };
+
+            const newPermissionObject = {
+              [cloudWatchIamRoleLogicalId]: JSON.parse(iamRoleTemplate),
+            };
+
+            _.merge(this.serverless.service.provider.compiledCloudFormationTemplate.Resources,
+              newCloudWatchEventRuleObject, newPermissionObject);
+          }
+        });
+      }
+    });
+    return BbPromise.resolve();
+  },
+};