Support for using existing or Terraform-managed task definitions

README.md

@@ -56,6 +56,18 @@ If you do not wish to store your task definition as a file in your git repositor
         aws ecs describe-task-definition --task-definition my-task-definition-family --query taskDefinition > task-definition.json
 ```
 
+If you don't want to create new revisions of your task definition, you can define the task definition family and revision as inputs for the action. By default, the action will use the latest revision of the task definition family if the revision is not specified.
+
+```yaml
+    - name: Deploy to Amazon ECS
+      uses: aws-actions/amazon-ecs-deploy-task-definition@v1
+      with:
+        task-definition: my-task-definition-family
+        service: my-service
+        cluster: my-cluster
+        wait-for-service-stability: true
+```
+
 ### Task definition container image values
 
 It is highly recommended that each time your GitHub Actions workflow runs and builds a new container image for deployment, a new container image ID is generated.  For example, use the commit ID as the new image's tag, instead of updating the 'latest' tag with the new image.  Using a unique container image ID for each deployment allows rolling back to a previous container image.

action.yml

@@ -5,7 +5,7 @@ branding:
   color: 'orange'
 inputs:
   task-definition:
-    description: 'The path to the ECS task definition file to register'
+    description: 'The path to the ECS task definition file to register or the name of the task definition family to use. If the task definition family is given, the action will use the latest ACTIVE revision of the task definition.'
     required: true
   desired-count:
     description: 'The number of instantiations of the task to place and keep running in your service.'

index.js

@@ -276,23 +276,50 @@ async function run() {
     const desiredCount = parseInt((core.getInput('desired-count', {required: false})));
 
 
-    // Register the task definition
-    core.debug('Registering the task definition');
     const taskDefPath = path.isAbsolute(taskDefinitionFile) ?
-      taskDefinitionFile :
-      path.join(process.env.GITHUB_WORKSPACE, taskDefinitionFile);
-    const fileContents = fs.readFileSync(taskDefPath, 'utf8');
-    const taskDefContents = maintainValidObjects(removeIgnoredAttributes(cleanNullKeys(yaml.parse(fileContents))));
-    let registerResponse;
-    try {
-      registerResponse = await ecs.registerTaskDefinition(taskDefContents).promise();
-    } catch (error) {
-      core.setFailed("Failed to register task definition in ECS: " + error.message);
-      core.debug("Task definition contents:");
-      core.debug(JSON.stringify(taskDefContents, undefined, 4));
-      throw(error);
+        taskDefinitionFile :
+        path.join(process.env.GITHUB_WORKSPACE, taskDefinitionFile);
+
+    const isExistingTaskDef = fs.existsSync(taskDefPath);
+
+    let taskDefArn;
+
+    if (!isExistingTaskDef) {
+      core.debug(`Searching for task definition ${taskDefinitionFile} in ECS`);
+      try {
+        const describeResponse = await ecs.describeTaskDefinition({
+          taskDefinition: taskDefinitionFile
+        }).promise();
+        const taskDef = describeResponse.taskDefinition;
+
+        if (!taskDef) {
+          throw new Error(`Task definition ${taskDefinitionFile} not found in ECS`);
+        }
+
+        core.debug(`Found task definition ${taskDef.taskDefinitionArn}`);
+        taskDefArn = taskDef.taskDefinitionArn;
+      } catch (error) {
+        core.setFailed("Failed to describe task definition in ECS: " + error.message);
+        throw(error);
+      }
     }
-    const taskDefArn = registerResponse.taskDefinition.taskDefinitionArn;
+
+    if (isExistingTaskDef) {
+      core.debug('Registering the task definition');
+      const fileContents = fs.readFileSync(taskDefPath, 'utf8');
+      const taskDefContents = maintainValidObjects(removeIgnoredAttributes(cleanNullKeys(yaml.parse(fileContents))));
+      let registerResponse;
+      try {
+        registerResponse = await ecs.registerTaskDefinition(taskDefContents).promise();
+      } catch (error) {
+        core.setFailed("Failed to register task definition in ECS: " + error.message);
+        core.debug("Task definition contents:");
+        core.debug(JSON.stringify(taskDefContents, undefined, 4));
+        throw(error);
+      }
+      taskDefArn = registerResponse.taskDefinition.taskDefinitionArn;
+    }
+
     core.setOutput('task-definition-arn', taskDefArn);
 
     // Update the service with the new task definition

index.test.js

@@ -7,12 +7,14 @@ jest.mock('@actions/core');
 jest.mock('fs', () => ({
     promises: { access: jest.fn() },
     readFileSync: jest.fn(),
+    existsSync: jest.fn().mockReturnValue(true)
 }));
 
 const mockEcsRegisterTaskDef = jest.fn();
 const mockEcsUpdateService = jest.fn();
 const mockEcsDescribeServices = jest.fn();
 const mockEcsWaiter = jest.fn();
+const mockEcsDescribeTaskDef = jest.fn();
 const mockCodeDeployCreateDeployment = jest.fn();
 const mockCodeDeployGetDeploymentGroup = jest.fn();
 const mockCodeDeployWaiter = jest.fn();
@@ -27,7 +29,8 @@ jest.mock('aws-sdk', () => {
             registerTaskDefinition: mockEcsRegisterTaskDef,
             updateService: mockEcsUpdateService,
             describeServices: mockEcsDescribeServices,
-            waitFor: mockEcsWaiter
+            waitFor: mockEcsWaiter,
+            describeTaskDefinition: mockEcsDescribeTaskDef
         })),
         CodeDeploy: jest.fn(() => ({
             createDeployment: mockCodeDeployCreateDeployment,
@@ -86,6 +89,14 @@ describe('Deploy to ECS', () => {
             };
         });
 
+        mockEcsDescribeTaskDef.mockImplementation(() => {
+            return {
+                promise() {
+                    return Promise.resolve({ taskDefinition: { taskDefinitionArn: 'task:def:arn' } });
+                }
+            };
+        })
+
         mockEcsUpdateService.mockImplementation(() => {
             return {
                 promise() {
@@ -151,6 +162,65 @@ describe('Deploy to ECS', () => {
         });
     });
 
+    test("try to get existing task definition ARN when user provides family instead of file", async () => {
+      fs.existsSync.mockReturnValueOnce(false);
+
+      core.getInput = jest
+        .fn()
+        .mockReturnValueOnce('task-def-family')
+        .mockReturnValueOnce('service-456')
+        .mockReturnValueOnce('cluster-789'); 
+
+      await run();
+
+      expect(core.setFailed).toHaveBeenCalledTimes(0);
+      expect(mockEcsDescribeTaskDef).toHaveBeenNthCalledWith(1, {
+        taskDefinition: "task-def-family"
+      });
+      expect(mockEcsRegisterTaskDef).not.toHaveBeenCalled();
+      expect(core.setOutput).toHaveBeenNthCalledWith(1, 'task-definition-arn', 'task:def:arn');
+      expect(mockEcsDescribeServices).toHaveBeenNthCalledWith(1, {
+        cluster: 'cluster-789',
+        services: ['service-456']
+      });
+      expect(mockEcsUpdateService).toHaveBeenNthCalledWith(1, {
+        cluster: 'cluster-789',
+        service: 'service-456',
+        taskDefinition: 'task:def:arn',
+        forceNewDeployment: false
+      });
+      expect(mockEcsWaiter).toHaveBeenCalledTimes(0);
+      expect(core.info).toBeCalledWith("Deployment started. Watch this deployment's progress in the Amazon ECS console: https://console.aws.amazon.com/ecs/home?region=fake-region#/clusters/cluster-789/services/service-456/events");
+    });
+
+    test("should be able to throw an error when the task definition family is not found", async () => {
+      fs.existsSync.mockReturnValueOnce(false);
+
+      core.getInput = jest
+        .fn()
+        .mockReturnValueOnce('task-def-family')
+        .mockReturnValueOnce('service-456')
+        .mockReturnValueOnce('cluster-789'); 
+
+      mockEcsDescribeTaskDef.mockImplementation(() => {
+        return {
+          promise() {
+            return Promise.resolve({ taskDefinition: null });
+          }
+        };
+      });
+
+      await run()
+
+      expect(mockEcsDescribeTaskDef).toHaveBeenNthCalledWith(1, {
+        taskDefinition: "task-def-family"
+      });
+      expect(core.setFailed).toHaveBeenCalledTimes(2);
+      expect(mockEcsRegisterTaskDef).not.toHaveBeenCalled();
+      expect(core.setOutput).not.toHaveBeenNthCalledWith(1, 'task-definition-arn', 'task:def:arn');
+      expect(core.info).not.toBeCalledWith("Deployment started. Watch this deployment's progress in the Amazon ECS console: https://console.aws.amazon.com/ecs/home?region=fake-region#/clusters/cluster-789/services/service-456/events");
+    });
+
     test('registers the task definition contents and updates the service', async () => {
         await run();
         expect(core.setFailed).toHaveBeenCalledTimes(0);