Support ARN being passed in as well as a file

README.md

@@ -104,6 +104,18 @@ The task definition file can be updated prior to deployment with the new contain
         wait-for-service-stability: true
 ```
 
+If you're using CloudFormation tools such as AWS CDK, Serverless Framework, or others to construct your task definition, you can directly pass the ARN of the task definition. For example:
+
+```yaml
+    - name: Deploy Amazon ECS task definition
+      uses: aws-actions/amazon-ecs-deploy-task-definition@v2
+      with:
+        task-definition-arn: arn:aws:ecs:<region>:<aws_account_id>:task-definition/<task_definition_name>:<revision_number>
+        service: my-service
+        cluster: my-cluster
+        wait-for-service-stability: true
+```
+
 ### Tags
 
 To turn on [Amazon ECS-managed tags](https://docs.aws.amazon.com/AmazonECS/latest/developerguide/ecs-using-tags.html#managed-tags) `aws:ecs:serviceName` and `aws:ecs:clusterName` for the tasks in the service or the standalone tasks by setting `enable-ecs-managed-tags`:

action.yml

@@ -5,8 +5,11 @@ branding:
   color: 'orange'
 inputs:
   task-definition:
-    description: 'The path to the ECS task definition file to register.'
-    required: true
+    description: 'The path to the ECS task definition file to register. Either this or task-definition-arn must be provided.'
+    required: false
+  task-definition-arn:
+    description: 'The ARN of an existing ECS task definition to deploy. Either this or task-definition must be provided.'
+    required: false
   desired-count:
     description: 'The number of instantiations of the task to place and keep running in your service.'
     required: false

dist/index.js

@@ -391,7 +391,8 @@ async function run() {
     });
 
     // Get inputs
-    const taskDefinitionFile = core.getInput('task-definition', { required: true });
+    const taskDefinitionArn = core.getInput('task-definition-arn', { required: false });
+    const taskDefinitionFile = core.getInput('task-definition', { required: false });
     const service = core.getInput('service', { required: false });
     const cluster = core.getInput('cluster', { required: false });
     const waitForService = core.getInput('wait-for-service-stability', { required: false });
@@ -411,23 +412,39 @@ async function run() {
     }
     const propagateTags = core.getInput('propagate-tags', { required: false }) || 'NONE';
 
-    // Register the task definition
-    core.debug('Registering the task definition');
-    const taskDefPath = path.isAbsolute(taskDefinitionFile) ?
+    let taskDefArn = null;
+
+    // Prioritize task-definition-arn if provided
+    if (taskDefinitionArn) {
+      taskDefArn = taskDefinitionArn;
+    } else if (taskDefinitionFile) {
+      // Fall back to task-definition file if provided
+      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);
-    } 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);
+        path.join(process.env.GITHUB_WORKSPACE, taskDefinitionFile);
+      const fileContents = fs.readFileSync(taskDefPath, 'utf8');
+      const taskDefContents = maintainValidObjects(removeIgnoredAttributes(cleanNullKeys(yaml.parse(fileContents))));
+      try {
+        const registerResponse = await ecs.registerTaskDefinition(taskDefContents);
+        taskDefArn = registerResponse.taskDefinition.taskDefinitionArn;
+      } 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);
+      }
+    } else {
+      // Error if neither is provided
+      core.setFailed('Either task-definition or task-definition-arn must be provided');
+      throw new Error('Either task-definition or task-definition-arn must be provided');
     }
-    const taskDefArn = registerResponse.taskDefinition.taskDefinitionArn;
+
+    if (!taskDefArn) {
+      core.setFailed('Task definition ARN is not defined');
+      throw new Error('Task definition ARN is not defined');
+    }
+
     core.setOutput('task-definition-arn', taskDefArn);
 
     // Run the task outside of the service

index.js

@@ -385,7 +385,8 @@ async function run() {
     });
 
     // Get inputs
-    const taskDefinitionFile = core.getInput('task-definition', { required: true });
+    const taskDefinitionArn = core.getInput('task-definition-arn', { required: false });
+    const taskDefinitionFile = core.getInput('task-definition', { required: false });
     const service = core.getInput('service', { required: false });
     const cluster = core.getInput('cluster', { required: false });
     const waitForService = core.getInput('wait-for-service-stability', { required: false });
@@ -405,23 +406,39 @@ async function run() {
     }
     const propagateTags = core.getInput('propagate-tags', { required: false }) || 'NONE';
 
-    // Register the task definition
-    core.debug('Registering the task definition');
-    const taskDefPath = path.isAbsolute(taskDefinitionFile) ?
+    let taskDefArn = null;
+
+    // Prioritize task-definition-arn if provided
+    if (taskDefinitionArn) {
+      taskDefArn = taskDefinitionArn;
+    } else if (taskDefinitionFile) {
+      // Fall back to task-definition file if provided
+      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);
-    } 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);
+        path.join(process.env.GITHUB_WORKSPACE, taskDefinitionFile);
+      const fileContents = fs.readFileSync(taskDefPath, 'utf8');
+      const taskDefContents = maintainValidObjects(removeIgnoredAttributes(cleanNullKeys(yaml.parse(fileContents))));
+      try {
+        const registerResponse = await ecs.registerTaskDefinition(taskDefContents);
+        taskDefArn = registerResponse.taskDefinition.taskDefinitionArn;
+      } 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);
+      }
+    } else {
+      // Error if neither is provided
+      core.setFailed('Either task-definition or task-definition-arn must be provided');
+      throw new Error('Either task-definition or task-definition-arn must be provided');
+    }
+
+    if (!taskDefArn) {
+      core.setFailed('Task definition ARN is not defined');
+      throw new Error('Task definition ARN is not defined');
     }
-    const taskDefArn = registerResponse.taskDefinition.taskDefinitionArn;
+
     core.setOutput('task-definition-arn', taskDefArn);
 
     // Run the task outside of the service