WIP: Adding plugin support

Plugins/asset_blend.py

@@ -0,0 +1,11 @@
+import pathlib
+
+
+category = "asset"
+supported_types = {
+    ".blend": "blend",
+}
+
+
+def loader(path: pathlib.Path):
+    pass

__init__.py

@@ -37,6 +37,8 @@
 from bpy.utils import previews
 from bpy.props import EnumProperty, StringProperty, BoolVectorProperty
 
+from . import plugin
+
 bl_info = {
     "name": "YAAM",
     "version": (0, 1),
@@ -1517,6 +1519,9 @@ def register():
     for cls in classes:
         bpy.utils.register_class(cls)
 
+    # TODO: Use this to handle all plugin needs.
+    plugin_manager = plugin.PluginManager.register()
+
     bpy.types.Scene.assets_dir = StringProperty(
         name="Asset Folder",
         subtype='DIR_PATH',

plugin.py

@@ -0,0 +1,81 @@
+import importlib.util
+import os
+import pathlib
+from enum import Enum
+from typing import Callable, List, Mapping
+
+TypeMap = Mapping[str, str]
+Loader = Callable[[pathlib.Path], None]
+
+
+class Category(Enum):
+    ASSET = "asset"
+    TEXTURE = "texture"
+
+
+class Plugin(object):
+    def __init__(self, category: Category, supported_type_map: TypeMap,
+                 loader: Loader):
+        self.__category = category
+        self.__supported_type_map = supported_type_map
+        self.__loader = loader
+
+    def category(self) -> Category:
+        return self.__category
+
+    def can_run(self, file_path: pathlib.Path) -> bool:
+        return file_path.suffix.lower() in self.__supported_type_map
+
+    def run(self, file_path: pathlib.Path):
+        self.__loader(file_path)
+
+
+class PluginManager(object):
+    def __init__(self):
+        self.__plugins: List[Plugin] = []
+        self.__search_paths: List[pathlib.Path] = []
+
+    def add_search_path(self, search_path: pathlib.Path):
+        self.__search_paths.append(search_path)
+
+    def register_plugins(self):
+        category_map = {
+            "asset": Category.ASSET,
+            "texture": Category.TEXTURE,
+        }
+
+        for search_path in self.__search_paths:
+            for module_path in search_path.glob("*.py"):
+                name = module_path.stem
+                spec = importlib.util.spec_from_file_location(name, module_path)
+                plugin = importlib.util.module_from_spec(spec)
+                spec.loader.exec_module(plugin)
+
+                if not hasattr(plugin, "loader"):
+                    continue
+                if not hasattr(plugin, "category"):
+                    continue
+                if not hasattr(plugin, "supported_types"):
+                    continue
+
+                if plugin.category not in category_map:
+                    raise RuntimeError("'{}' is not a valid category".format(plugin.category))
+
+                self.__plugins.append(Plugin(category_map[plugin.category], plugin.supported_types, plugin.loader))
+
+    @classmethod
+    def register(cls):
+        manager = cls()
+
+        # Internal plugin path
+        internal_plugin_path = pathlib.Path(__file__).parent / "Plugins"
+        manager.add_search_path(internal_plugin_path)
+
+        # Environment variable pugin path
+        search_paths = os.environ.get("YAAM_PLUGIN_PATHS", "")
+
+        if search_paths:
+            for search_path in search_paths.split(os.pathsep):
+                manager.add_search_path(pathlib.Path(search_path))
+
+        manager.register_plugins()