fix(remote-build): minor edge cases found with snapcraft

craft_application/remote/git.py

@@ -253,7 +253,10 @@ def push_url(  # pylint: disable=too-many-branches
         # temporarily call git directly due to libgit2 bug that unable to push
         # large repos using https. See https://github.com/libgit2/libgit2/issues/6385
         # and https://github.com/snapcore/snapcraft/issues/4478
-        cmd: list[str] = ["git", "push", remote_url, refspec, "--progress"]
+        # Force push in case this repository already exists. The repository is always
+        # going to exist solely for remote builds, so the only potential issue here is a
+        # race condition with multiple remote builds on the same machine.
+        cmd: list[str] = ["git", "push", "--force", remote_url, refspec, "--progress"]
         if push_tags:
             cmd.append("--tags")
 

craft_application/services/remotebuild.py

@@ -258,7 +258,9 @@ def _ensure_repository(
         work_tree = WorkTree(self._app.name, self._name, project_dir)
         work_tree.init_repo()
         try:
-            lp_repository = self.lp.new_repository(self._name, self._lp_project.name)
+            lp_repository = self.lp.new_repository(
+                self._name, project=self._lp_project.name
+            )
         except launchpadlib.errors.HTTPError:
             lp_repository = self.lp.get_repository(
                 name=self._name, project=self._lp_project.name
@@ -289,21 +291,30 @@ def _ensure_recipe(
         repository: launchpad.models.GitRepository,
         **kwargs: Any,  # noqa: ANN401
     ) -> launchpad.models.Recipe:
-        """Create a new recipe."""
-        # There are 3 different ways this can fail in expected ways, all of them HTTPErrors:
-        #
-        # 1. Recipe doesn't exist (or you don't have access to see it)
-        # 2. You don't have access to delete the recipe
-        # 3. There is an ongoing build with the recipep
-        #
-        # In case 1, we don't care and are about to make the new recipe anyway.
-        # In the other cases, the errors from `new()` end up being more useful.
-        with contextlib.suppress(launchpadlib.errors.HTTPError):
+        """Get a recipe or create it if it doesn't exist."""
+
+        with contextlib.suppress(ValueError):  # Recipe doesn't exist
             recipe = self._get_recipe()
             recipe.delete()
 
+        return self._new_recipe(name, repository, **kwargs)
+
+    def _new_recipe(
+        self,
+        name: str,
+        repository: launchpad.models.GitRepository,
+        **kwargs: Any,  # noqa: ANN401
+    ) -> launchpad.models.Recipe:
+        """Create a new recipe for the given repository"""
+        repository.lp_refresh()  # Prevents a race condition on new repositories.
+        git_ref = parse.urlparse(str(repository.git_https_url)).path + "/+ref/main"
         return self.RecipeClass.new(
-            self.lp, name, self.lp.username, git_ref=repository.git_https_url, **kwargs
+            self.lp,
+            name,
+            self.lp.username,
+            git_ref=git_ref,
+            project=self._lp_project.name,
+            **kwargs,
         )
 
     def _get_recipe(self) -> launchpad.models.Recipe:

tests/unit/services/test_remotebuild.py

@@ -186,6 +186,23 @@ def test_ensure_repository_already_exists(
     assert expiry > datetime.datetime.now(tz=tz)
 
 
+def test_create_new_recipe(monkeypatch, tmp_path, remote_build_service, mock_lp_project):
+    """Test that _new_recipe works correctly."""
+    remote_build_service._lp_project = mock_lp_project
+    remote_build_service.RecipeClass = mock.Mock()
+    repo = mock.Mock(git_https_url="https://localhost/~me/some-project/+git/my-repo")
+
+    remote_build_service._new_recipe("test-recipe", repo)
+
+    remote_build_service.RecipeClass.new.assert_called_once_with(
+        remote_build_service.lp,
+        "test-recipe",
+        "craft_test_user",
+        git_ref="/~me/some-project/+git/my-repo/+ref/main",
+        project="craft_test_user-craft-remote-build",
+    )
+
+
 def test_not_setup(remote_build_service):
     with pytest.raises(RuntimeError):
         all(remote_build_service.monitor_builds())