fix: compose error on "dev --mount=learning:..."

When mounting a directory in a dev-only container, such as the
"learning" mfe, docker-compose is failing because it is attempting to
run "docker-compose stop" in the local context -- which knows nothing
about the learning container.

To resolve this, we store tmp volumes either in the local or dev
docker-compose.yml, and load either one depending on the context.

CHANGELOG.md

@@ -4,6 +4,7 @@ Note: Breaking changes between versions are indicated by "💥".
 
 ## Unreleased
 
+- [Fix] "The Compose file is invalid" error on mounting dev-only folders.
 - [Fix] CMS settings in development.
 
 ## v13.2.0 (2022-04-24)

tutor/commands/compose.py

@@ -19,6 +19,7 @@ class ComposeJobRunner(jobs.BaseComposeJobRunner):
         self.project_name = ""
         self.docker_compose_files: t.List[str] = []
         self.docker_compose_job_files: t.List[str] = []
+        self.docker_compose_tmp_path = ""
 
     def docker_compose(self, *command: str) -> int:
         """

tutor/commands/dev.py

@@ -18,10 +18,11 @@ class DevJobRunner(compose.ComposeJobRunner):
         """
         super().__init__(root, config)
         self.project_name = get_typed(self.config, "DEV_PROJECT_NAME", str)
+        self.docker_compose_tmp_path = tutor_env.pathjoin(self.root, "dev", "docker-compose.tmp.yml")
         self.docker_compose_files += [
             tutor_env.pathjoin(self.root, "local", "docker-compose.yml"),
             tutor_env.pathjoin(self.root, "dev", "docker-compose.yml"),
-            tutor_env.pathjoin(self.root, "local", "docker-compose.tmp.yml"),
+            self.docker_compose_tmp_path,
             tutor_env.pathjoin(self.root, "local", "docker-compose.override.yml"),
             tutor_env.pathjoin(self.root, "dev", "docker-compose.override.yml"),
         ]

tutor/commands/local.py

@@ -20,10 +20,11 @@ class LocalJobRunner(compose.ComposeJobRunner):
         """
         super().__init__(root, config)
         self.project_name = get_typed(self.config, "LOCAL_PROJECT_NAME", str)
+        self.docker_compose_tmp_path = tutor_env.pathjoin(self.root, "dev", "docker-compose.tmp.yml")
         self.docker_compose_files += [
             tutor_env.pathjoin(self.root, "local", "docker-compose.yml"),
             tutor_env.pathjoin(self.root, "local", "docker-compose.prod.yml"),
-            tutor_env.pathjoin(self.root, "local", "docker-compose.tmp.yml"),
+            self.docker_compose_tmp_path,
             tutor_env.pathjoin(self.root, "local", "docker-compose.override.yml"),
         ]
         self.docker_compose_job_files += [