chore(pre-deploy): warn about depends_on: service_completed_successfully to use pre-deploy hook instead

pkg/client/compose/project_test.go

@@ -239,6 +239,25 @@ networks:
 			warnCount:    1,
 			warnContains: []string{"networks"},
 		},
+		{
+			name: "unsupported depends_on service_completed_successfully",
+			composeYAML: `services:
+  migrate:
+    image: alpine
+    command: ["true"]
+  app:
+    image: nginx
+    depends_on:
+      migrate:
+        condition: service_completed_successfully
+`,
+			warnCount: 1,
+			warnContains: []string{
+				"service_completed_successfully",
+				"pre-deploy hook",
+				"https://uncloud.run/docs/guides/deployments/pre-deploy-hooks",
+			},
+		},
 		{
 			name: "multiple unsupported features",
 			composeYAML: `services:

pkg/client/compose/service.go

@@ -495,6 +495,21 @@ func validateServicesFeatures(project *types.Project) []error {
 				errs = append(errs, err(service.Name, "networks"))
 			}
 		}
+
+		// Err about depends_on conditions 'service_completed_successfully' that we do not support because services in
+		// Uncloud are long-running. Services that run to completion need a separate abstraction, e.g. a Job.
+		// Plus we don't want the lifecycle of a service to control the lifecycle of another one. It should be fully
+		// owned. Otherwise, it's hard to make the behaviour deterministic when each service could also be deployed and
+		// managed independently.
+		for depName, dep := range service.DependsOn {
+			if dep.Condition == types.ServiceConditionCompletedSuccessfully {
+				errs = append(errs, fmt.Errorf(
+					"service '%s': depends_on condition '%s' on service '%s' is not supported, "+
+						"use a pre-deploy hook instead: %s",
+					service.Name, types.ServiceConditionCompletedSuccessfully, depName,
+					"https://uncloud.run/docs/guides/deployments/pre-deploy-hooks"))
+			}
+		}
 	}
 
 	return errs

website/docs/8-compose-file-reference/1-support-matrix.md

@@ -11,7 +11,7 @@ If you rely on a specific Compose feature that is not supported by Uncloud, plea
 :::
 
 | Feature                          | Support Status     | Notes                                                                                                                                      |
-|----------------------------------|--------------------|----------------------------------------------------------------------------------------------------------------|
+|----------------------------------|--------------------|--------------------------------------------------------------------------------------------------------------------------------------------|
 | **Services**                     |                    |                                                                                                                                            |
 | `build`                          | ✅ Supported        | Build context and Dockerfile                                                                                                               |
 | `cap_add`                        | ✅ Supported        | Additional kernel [capabilities](https://man7.org/linux/man-pages/man7/capabilities.7.html)                                                |
@@ -19,7 +19,7 @@ If you rely on a specific Compose feature that is not supported by Uncloud, plea
 | `command`                        | ✅ Supported        | Override container command                                                                                                                 |
 | `configs`                        | ✅ Supported        | File-based and inline configs                                                                                                              |
 | `cpus`                           | ✅ Supported        | CPU limit                                                                                                                                  |
-| `depends_on`                     | ⚠️ Limited         | Services deployed in order but conditions not checked                                                          |
+| `depends_on`                     | ⚠️ Limited         | Deployed in dependency order. Use [pre-deploy hooks](../4-guides/1-deployments/5-pre-deploy-hooks.md) for `service_completed_successfully` |
 | `devices`                        | ✅ Supported        | Device mappings                                                                                                                            |
 | `dns`                            | ❌ Not supported    | Built-in service discovery                                                                                                                 |
 | `dns_search`                     | ❌ Not supported    | Built-in service discovery                                                                                                                 |