Add register_middleware hook

fps/app.py

@@ -271,6 +271,57 @@ def _load_routers(app: FastAPI) -> None:
         logger.info("No plugin API router to load")
 
 
+def _load_middlewares(app: FastAPI) -> None:
+
+    pm = _get_pluggin_manager(HookType.MIDDLEWARE)
+
+    grouped_middlewares = _grouped_hookimpls_results(pm.hook.middleware)
+
+    if grouped_middlewares:
+
+        pkg_names = {get_pkg_name(p, strip_fps=False) for p in grouped_middlewares}
+        logger.info(f"Loading middlewares from plugin package(s) {pkg_names}")
+
+        for p, middlewares in grouped_middlewares.items():
+            p_name = Config.plugin_name(p)
+            plugin_config = Config.from_name(p_name)
+
+            disabled = (
+                plugin_config
+                and not plugin_config.enabled
+                or p_name in Config(FPSConfig).disabled_plugins
+                or (
+                    Config(FPSConfig).enabled_plugins
+                    and p_name not in Config(FPSConfig).enabled_plugins
+                )
+            )
+            if not middlewares or disabled:
+                disabled_msg = " (disabled)" if disabled else ""
+                logger.info(
+                    f"No middleware registered for plugin '{p_name}'{disabled_msg}"
+                )
+                continue
+
+            for plugin_middleware, plugin_kwargs in middlewares:
+                if plugin_middleware in [
+                    middleware.cls for middleware in app.user_middleware
+                ]:
+                    logger.error(
+                        f"Redefinition of middleware '{plugin_middleware}' is not allowed."
+                    )
+                    exit(1)
+                app.add_middleware(
+                    plugin_middleware,
+                    **plugin_kwargs,
+                )
+
+            logger.info(
+                f"{len(middlewares)} middleware(s) added from plugin '{p_name}'"
+            )
+    else:
+        logger.info("No plugin middleware to load")
+
+
 def create_app():
 
     logging.getLogger("fps")
@@ -283,6 +334,7 @@ def create_app():
 
     _load_routers(app)
     _load_exceptions_handlers(app)
+    _load_middlewares(app)
 
     Config.check_not_used_sections()
 

fps/hooks.py

@@ -12,6 +12,7 @@ class HookType(Enum):
     ROUTER = "fps_router"
     CONFIG = "fps_config"
     EXCEPTION = "fps_exception"
+    MIDDLEWARE = "fps_middleware"
 
 
 @pluggy.HookspecMarker(HookType.ROUTER.value)
@@ -75,3 +76,17 @@ def plugin_name_callback() -> str:
     return pluggy.HookimplMarker(HookType.CONFIG.value)(
         function=plugin_name_callback, specname="plugin_name"
     )
+
+
+@pluggy.HookspecMarker(HookType.MIDDLEWARE.value)
+def middleware() -> Tuple[type, Dict[str, Any]]:
+    pass
+
+
+def register_middleware(m: type, **kwargs: Dict[str, Any]):
+    def middleware_callback() -> Tuple[type, Dict[str, Any]]:
+        return m, kwargs
+
+    return pluggy.HookimplMarker(HookType.MIDDLEWARE.value)(
+        function=middleware_callback, specname="middleware"
+    )