Support read charmcraft.yaml

Try read unified charmcraft.yaml first, that may included metadata,
actions, and config. Ignore metadata.yaml, actions.yaml, config.yaml if
they are exists in charmcraft.yaml

ops/charm.py

@@ -1118,18 +1118,22 @@ def __init__(self, raw: Optional[Dict[str, Any]] = None,
     @classmethod
     def from_yaml(
             cls, metadata: Union[str, TextIO],
-            actions: Optional[Union[str, TextIO]] = None) -> 'CharmMeta':
+            actions: Optional[Union[str, TextIO, Dict[str, Any]]] = None) -> 'CharmMeta':
         """Instantiate a :class:`CharmMeta` from a YAML description of ``metadata.yaml``.
 
         Args:
             metadata: A YAML description of charm metadata (name, relations, etc.)
                 This can be a simple string, or a file-like object (passed to ``yaml.safe_load``).
-            actions: YAML description of Actions for this charm (e.g., actions.yaml)
+            actions: YAML description of Actions for this charm (e.g., actions.yaml),
+                or a mapped dictionary of actions that could come from charmcraft.yaml.
         """
         meta = yaml.safe_load(metadata)
         raw_actions = {}
         if actions is not None:
-            raw_actions = cast(Optional[Dict[str, Any]], yaml.safe_load(actions))
+            if isinstance(actions, dict):
+                raw_actions = actions
+            else:
+                raw_actions = cast(Optional[Dict[str, Any]], yaml.safe_load(actions))
             if raw_actions is None:
                 raw_actions = {}
         return cls(meta, raw_actions)

ops/main.py

@@ -32,6 +32,7 @@
 import ops.framework
 import ops.model
 import ops.storage
+from ops._private import yaml
 from ops.charm import CharmMeta
 from ops.jujuversion import JujuVersion
 from ops.log import setup_root_logging
@@ -374,6 +375,8 @@ def main(charm_class: Type[ops.charm.CharmBase],
             are running on a new enough Juju default to controller-side storage,
             otherwise local storage is used.
     """
+    metadata: Optional[str] = None
+    actions_metadata: Optional[Union[str, Dict[str, Any]]] = None
     charm_dir = _get_charm_dir()
 
     model_backend = ops.model._ModelBackend()
@@ -384,12 +387,28 @@ def main(charm_class: Type[ops.charm.CharmBase],
     dispatcher = _Dispatcher(charm_dir)
     dispatcher.run_any_legacy_hook()
 
-    metadata = (charm_dir / 'metadata.yaml').read_text()
-    actions_meta = charm_dir / 'actions.yaml'
-    if actions_meta.exists():
-        actions_metadata = actions_meta.read_text()
-    else:
-        actions_metadata = None
+    # Check charmcraft.yaml first and see if it has the metadata data in it.
+    charmcraft_meta = charm_dir / "charmcraft.yaml"
+    if charmcraft_meta.exists():
+        charmcraft_yaml = charmcraft_meta.read_text()
+        charmcraft_metadata: dict[str, Any] = yaml.safe_load(charmcraft_yaml)
+        if any(
+            meta_key in charmcraft_metadata for meta_key in ("name", "summary", "description")
+        ):
+            # Unrelated keys in the charmcraft.yaml file will be ignored.
+            metadata = charmcraft_yaml
+
+        # This could be None if the charmcraft.yaml not include the actions key.
+        # Should fall back to the actions.yaml file.
+        actions_metadata = charmcraft_metadata.get("actions")
+
+    if not metadata:
+        metadata = (charm_dir / "metadata.yaml").read_text()
+
+    if not actions_metadata:
+        actions_meta = charm_dir / "actions.yaml"
+        if actions_meta.exists():
+            actions_metadata = actions_meta.read_text()
 
     meta = CharmMeta.from_yaml(metadata, actions_metadata)
     model = ops.model.Model(meta, model_backend)

ops/testing.py

@@ -394,9 +394,30 @@ def _create_meta(self, charm_metadata: Optional[YAMLStringOrFile],
         """Create a CharmMeta object.
 
         Handle the cases where a user doesn't supply explicit metadata snippets.
+        Will try to load metadata/config from charm_dir/charmcraft.yaml first, then
+        charm_dir/metadata.yaml and/or charm_dir/actions.yaml if charmcraft.yaml
+        not include metadata and/or actions.
         """
         filename = inspect.getfile(self._charm_cls)
         charm_dir = pathlib.Path(filename).parents[1]
+        charmcraft_yaml: Optional[str] = None
+        charmcraft_metadata: Optional[dict[str, Any]] = None
+
+        # Check charmcraft.yaml and load it if it exists
+        charmcraft_meta = charm_dir / "charmcraft.yaml"
+        if charmcraft_meta.exists():
+            self._charm_dir = charm_dir
+            charmcraft_yaml = charmcraft_meta.read_text()
+            charmcraft_metadata = yaml.safe_load(charmcraft_yaml)
+
+        # Add metadata from charmcraft.yaml if no metadata is provided
+        # Should fall back to metadata.yaml if both are not provided
+        if charm_metadata is None and charmcraft_metadata:
+            if any(
+                meta_key in charmcraft_metadata for meta_key in ("name", "summary", "description")
+            ):
+                # Unrelated keys in the charmcraft.yaml file will be ignored.
+                charm_metadata = charmcraft_yaml
 
         if charm_metadata is None:
             metadata_path = charm_dir / 'metadata.yaml'
@@ -409,6 +430,11 @@ def _create_meta(self, charm_metadata: Optional[YAMLStringOrFile],
         elif isinstance(charm_metadata, str):
             charm_metadata = dedent(charm_metadata)
 
+        # Add actions from charmcraft.yaml if no actions are provided
+        # Should fall back to actions.yaml if both are not provided
+        if action_metadata is None and charmcraft_metadata:
+            action_metadata = charmcraft_metadata.get("actions")
+
         if action_metadata is None:
             actions_path = charm_dir / 'actions.yaml'
             if actions_path.is_file():
@@ -422,12 +448,23 @@ def _create_meta(self, charm_metadata: Optional[YAMLStringOrFile],
     def _get_config(self, charm_config: Optional['YAMLStringOrFile']):
         """If the user passed a config to Harness, use it.
 
-        Otherwise, attempt to load one from charm_dir/config.yaml.
+        Otherwise, attempt to load one from charm_dir/charmcraft.yaml, then
+        charm_dir/config.yaml if config is not provided in charmcraft.yaml.
         """
         filename = inspect.getfile(self._charm_cls)
         charm_dir = pathlib.Path(filename).parents[1]
-
-        if charm_config is None:
+        config: Optional[dict[str, Any]] = None
+
+        # Check charmcraft.yaml first if no config is provided
+        charmcraft_meta = charm_dir / "charmcraft.yaml"
+        if charm_config is None and charmcraft_meta.exists():
+            self._charm_dir = charm_dir
+            charmcraft_yaml = charmcraft_meta.read_text()
+            charmcraft_metadata: dict[str, Any] = yaml.safe_load(charmcraft_yaml)
+            config = charmcraft_metadata.get("config")
+
+        # Add config from charmcraft.yaml if no config is provided
+        if config is None and charm_config is None:
             config_path = charm_dir / 'config.yaml'
             if config_path.is_file():
                 charm_config = config_path.read_text()
@@ -438,8 +475,10 @@ def _get_config(self, charm_config: Optional['YAMLStringOrFile']):
         elif isinstance(charm_config, str):
             charm_config = dedent(charm_config)
 
-        assert isinstance(charm_config, str)  # type guard
-        config = yaml.safe_load(charm_config)
+        # If we have a config dict already, ignore the charm_config
+        if not config:
+            assert isinstance(charm_config, str)  # type guard
+            config = yaml.safe_load(charm_config)
 
         if not isinstance(config, dict):
             raise TypeError(config)