fix: use propagateTags service value

action.yml

@@ -74,7 +74,7 @@ inputs:
     description: "Determines whether to turn on Amazon ECS managed tags 'aws:ecs:serviceName' and 'aws:ecs:clusterName' for the tasks in the service."
     required: false
   propagate-tags:
-    description: "Determines to propagate the tags from the 'SERVICE' to the task. Will default to 'NONE'."
+    description: "Determines to propagate the tags from the 'SERVICE' to the task. Will default to service propagateTags value ('NONE' if not set at service creation)."
     required: false
 outputs:
   task-definition-arn:

index.js

@@ -403,7 +403,24 @@ async function run() {
     if (enableECSManagedTagsInput !== '') {
       enableECSManagedTags = enableECSManagedTagsInput.toLowerCase() === 'true';
     }
-    const propagateTags = core.getInput('propagate-tags', { required: false }) || 'NONE';
+
+    // get the current propagateTags of the service
+    // set it to NONE if api answer null (old services?)
+    let currentPropagateTags = 'NONE';
+    try {
+      describeServicesResponse = await ecs.describeServices({
+        services: [service],
+        cluster: cluster
+      })
+      if (describeServicesResponse.services[0].propagateTags != null) {
+        currentPropagateTags = describeServicesResponse.services[0].propagateTags;
+      }
+    } catch (error) {
+      core.setFailed("Failed to get current 'propagateTags' of the service: " + error.message);
+      throw(error);
+    }
+    core.debug(`Current service 'propagateTags' value: ${currentPropagateTags}`);
+    const propagateTags = core.getInput('propagate-tags', { required: false }) || currentPropagateTags;
 
     // Register the task definition
     core.debug('Registering the task definition');