asgi/wsgi mounting implemented

pyserve/__init__.py

@@ -2,10 +2,31 @@
 PyServe - HTTP web server written on Python
 """
 
-__version__ = "0.7.0"
+__version__ = "0.8.0"
 __author__ = "Ilya Glazunov"
 
 from .server import PyServeServer
 from .config import Config
+from .asgi_mount import (
+    ASGIAppLoader,
+    ASGIMountManager,
+    MountedApp,
+    create_fastapi_app,
+    create_flask_app,
+    create_django_app,
+    create_starlette_app,
+)
 
-__all__ = ["PyServeServer", "Config", "__version__"]
+__all__ = [
+    "PyServeServer",
+    "Config",
+    "__version__",
+    # ASGI mounting
+    "ASGIAppLoader",
+    "ASGIMountManager",
+    "MountedApp",
+    "create_fastapi_app",
+    "create_flask_app",
+    "create_django_app",
+    "create_starlette_app",
+]

pyserve/asgi_mount.py

@@ -0,0 +1,311 @@
+"""
+ASGI Application Mount Module
+
+This module provides functionality to mount external ASGI/WSGI applications
+(FastAPI, Flask, Django, etc.) at specified paths within PyServe.
+"""
+
+import importlib
+import sys
+from pathlib import Path
+from typing import Dict, Any, Optional, Callable, cast
+from starlette.types import ASGIApp, Receive, Scope, Send
+
+from .logging_utils import get_logger
+
+logger = get_logger(__name__)
+
+
+class ASGIAppLoader:
+    def __init__(self):
+        self._apps: Dict[str, ASGIApp] = {}
+        self._wsgi_adapters: Dict[str, ASGIApp] = {}
+
+    def load_app(
+        self,
+        app_path: str,
+        app_type: str = "asgi",
+        module_path: Optional[str] = None,
+        factory: bool = False,
+        factory_args: Optional[Dict[str, Any]] = None,
+    ) -> Optional[ASGIApp]:
+        try:
+            if module_path:
+                module_dir = Path(module_path).resolve()
+                if str(module_dir) not in sys.path:
+                    sys.path.insert(0, str(module_dir))
+                    logger.debug(f"Added {module_dir} to sys.path")
+
+            if ":" in app_path:
+                module_name, attr_name = app_path.rsplit(":", 1)
+            else:
+                module_name = app_path
+                attr_name = "app"
+
+            module = importlib.import_module(module_name)
+
+            app_or_factory = getattr(module, attr_name)
+
+            if factory:
+                factory_args = factory_args or {}
+                app = app_or_factory(**factory_args)
+                logger.info(f"Created app from factory: {app_path}")
+            else:
+                app = app_or_factory
+                logger.info(f"Loaded app: {app_path}")
+
+            if app_type == "wsgi":
+                app = self._wrap_wsgi(app)
+                logger.info(f"Wrapped WSGI app: {app_path}")
+
+            self._apps[app_path] = app
+            return app
+
+        except ImportError as e:
+            logger.error(f"Failed to import application {app_path}: {e}")
+            return None
+        except AttributeError as e:
+            logger.error(f"Failed to get attribute from {app_path}: {e}")
+            return None
+        except Exception as e:
+            logger.error(f"Failed to load application {app_path}: {e}")
+            return None
+
+    def _wrap_wsgi(self, wsgi_app: Callable) -> ASGIApp:
+        try:
+            from a2wsgi import WSGIMiddleware
+            return cast(ASGIApp, WSGIMiddleware(wsgi_app))
+        except ImportError:
+            logger.warning("a2wsgi not installed, trying asgiref")
+            try:
+                from asgiref.wsgi import WsgiToAsgi
+                return cast(ASGIApp, WsgiToAsgi(wsgi_app))
+            except ImportError:
+                logger.error(
+                    "Neither a2wsgi nor asgiref installed. "
+                    "Install with: pip install a2wsgi or pip install asgiref"
+                )
+                raise ImportError(
+                    "WSGI adapter not available. Install a2wsgi or asgiref."
+                )
+
+    def get_app(self, app_path: str) -> Optional[ASGIApp]:
+        return self._apps.get(app_path)
+
+    def reload_app(self, app_path: str, **kwargs: Any) -> Optional[ASGIApp]:
+        if app_path in self._apps:
+            del self._apps[app_path]
+
+        if ":" in app_path:
+            module_name, _ = app_path.rsplit(":", 1)
+        else:
+            module_name = app_path
+
+        if module_name in sys.modules:
+            importlib.reload(sys.modules[module_name])
+
+        return self.load_app(app_path, **kwargs)
+
+
+class MountedApp:
+    def __init__(
+        self,
+        path: str,
+        app: ASGIApp,
+        name: str = "",
+        strip_path: bool = True,
+    ):
+        self.path = path.rstrip("/")
+        self.app = app
+        self.name = name or path
+        self.strip_path = strip_path
+
+    def matches(self, request_path: str) -> bool:
+        if self.path == "":
+            return True
+        return request_path == self.path or request_path.startswith(f"{self.path}/")
+
+    def get_modified_path(self, original_path: str) -> str:
+        if not self.strip_path:
+            return original_path
+
+        if self.path == "":
+            return original_path
+
+        new_path = original_path[len(self.path):]
+        return new_path if new_path else "/"
+
+
+class ASGIMountManager:
+    def __init__(self):
+        self._mounts: list[MountedApp] = []
+        self._loader = ASGIAppLoader()
+
+    def mount(
+        self,
+        path: str,
+        app: Optional[ASGIApp] = None,
+        app_path: Optional[str] = None,
+        app_type: str = "asgi",
+        module_path: Optional[str] = None,
+        factory: bool = False,
+        factory_args: Optional[Dict[str, Any]] = None,
+        name: str = "",
+        strip_path: bool = True,
+    ) -> bool:
+        if app is None and app_path is None:
+            logger.error("Either 'app' or 'app_path' must be provided")
+            return False
+
+        if app is None:
+            app = self._loader.load_app(
+                app_path=app_path,  # type: ignore
+                app_type=app_type,
+                module_path=module_path,
+                factory=factory,
+                factory_args=factory_args,
+            )
+            if app is None:
+                return False
+
+        mounted = MountedApp(
+            path=path,
+            app=app,
+            name=name or app_path or "unnamed",
+            strip_path=strip_path,
+        )
+
+        self._mounts.append(mounted)
+        self._mounts.sort(key=lambda m: len(m.path), reverse=True)
+
+        logger.info(f"Mounted application '{mounted.name}' at path '{path}'")
+        return True
+
+    def unmount(self, path: str) -> bool:
+        for i, mount in enumerate(self._mounts):
+            if mount.path == path.rstrip("/"):
+                del self._mounts[i]
+                logger.info(f"Unmounted application at path '{path}'")
+                return True
+        return False
+
+    def get_mount(self, request_path: str) -> Optional[MountedApp]:
+        for mount in self._mounts:
+            if mount.matches(request_path):
+                return mount
+        return None
+
+    async def handle_request(
+        self,
+        scope: Scope,
+        receive: Receive,
+        send: Send,
+    ) -> bool:
+        if scope["type"] != "http":
+            return False
+
+        path = scope.get("path", "/")
+        mount = self.get_mount(path)
+
+        if mount is None:
+            return False
+
+        modified_scope = dict(scope)
+        if mount.strip_path:
+            modified_scope["path"] = mount.get_modified_path(path)
+            modified_scope["root_path"] = scope.get("root_path", "") + mount.path
+
+        logger.debug(
+            f"Routing request to mounted app '{mount.name}': "
+            f"{path} -> {modified_scope['path']}"
+        )
+
+        try:
+            await mount.app(modified_scope, receive, send)
+            return True
+        except Exception as e:
+            logger.error(f"Error in mounted app '{mount.name}': {e}")
+            raise
+
+    @property
+    def mounts(self) -> list[MountedApp]:
+        return self._mounts.copy()
+
+    def list_mounts(self) -> list[Dict[str, Any]]:
+        return [
+            {
+                "path": mount.path,
+                "name": mount.name,
+                "strip_path": mount.strip_path,
+            }
+            for mount in self._mounts
+        ]
+
+
+def create_fastapi_app(
+    app_path: str,
+    module_path: Optional[str] = None,
+    factory: bool = False,
+    factory_args: Optional[Dict[str, Any]] = None,
+) -> Optional[ASGIApp]:
+    loader = ASGIAppLoader()
+    return loader.load_app(
+        app_path=app_path,
+        app_type="asgi",
+        module_path=module_path,
+        factory=factory,
+        factory_args=factory_args,
+    )
+
+
+def create_flask_app(
+    app_path: str,
+    module_path: Optional[str] = None,
+    factory: bool = False,
+    factory_args: Optional[Dict[str, Any]] = None,
+) -> Optional[ASGIApp]:
+    loader = ASGIAppLoader()
+    return loader.load_app(
+        app_path=app_path,
+        app_type="wsgi",
+        module_path=module_path,
+        factory=factory,
+        factory_args=factory_args,
+    )
+
+
+def create_django_app(
+    settings_module: str,
+    module_path: Optional[str] = None,
+) -> Optional[ASGIApp]:
+    import os
+
+    if module_path:
+        module_dir = Path(module_path).resolve()
+        if str(module_dir) not in sys.path:
+            sys.path.insert(0, str(module_dir))
+
+    os.environ.setdefault("DJANGO_SETTINGS_MODULE", settings_module)
+
+    try:
+        from django.core.asgi import get_asgi_application
+        return get_asgi_application()
+    except ImportError as e:
+        logger.error(f"Failed to load Django application: {e}")
+        return None
+
+
+def create_starlette_app(
+    app_path: str,
+    module_path: Optional[str] = None,
+    factory: bool = False,
+    factory_args: Optional[Dict[str, Any]] = None,
+) -> Optional[ASGIApp]:
+    loader = ASGIAppLoader()
+    return loader.load_app(
+        app_path=app_path,
+        app_type="asgi",
+        module_path=module_path,
+        factory=factory,
+        factory_args=factory_args,
+    )

pyserve/extensions.py

@@ -138,6 +138,74 @@ class MonitoringExtension(Extension):
         }
 
 
+class ASGIExtension(Extension):
+    def __init__(self, config: Dict[str, Any]):
+        super().__init__(config)
+        from .asgi_mount import ASGIMountManager, create_django_app
+
+        self.mount_manager = ASGIMountManager()
+        self._load_mounts(config.get("mounts", []))
+
+    def _load_mounts(self, mounts: List[Dict[str, Any]]) -> None:
+        from .asgi_mount import create_django_app
+
+        for mount_config in mounts:
+            path = mount_config.get("path", "/")
+
+            if "django_settings" in mount_config:
+                app = create_django_app(
+                    settings_module=mount_config["django_settings"],
+                    module_path=mount_config.get("module_path"),
+                )
+                if app:
+                    self.mount_manager.mount(
+                        path=path,
+                        app=app,
+                        name=mount_config.get("name", f"django:{mount_config['django_settings']}"),
+                        strip_path=mount_config.get("strip_path", True),
+                    )
+                continue
+
+            self.mount_manager.mount(
+                path=path,
+                app_path=mount_config.get("app_path"),
+                app_type=mount_config.get("app_type", "asgi"),
+                module_path=mount_config.get("module_path"),
+                factory=mount_config.get("factory", False),
+                factory_args=mount_config.get("factory_args"),
+                name=mount_config.get("name", ""),
+                strip_path=mount_config.get("strip_path", True),
+            )
+
+    async def process_request(self, request: Request) -> Optional[Response]:
+        path = request.url.path
+        mount = self.mount_manager.get_mount(path)
+
+        if mount is not None:
+            # Store mount info in request state for middleware to use
+            request.state.asgi_mount = mount
+            # Return a special marker response that middleware will intercept
+            return None  # Will be handled by get_asgi_handler
+
+        return None
+
+    async def process_response(self, request: Request, response: Response) -> Response:
+        return response
+
+    def get_asgi_handler(self, request: Request) -> Optional[Any]:
+        path = request.url.path
+        return self.mount_manager.get_mount(path)
+
+    def get_metrics(self) -> Dict[str, Any]:
+        return {
+            "asgi_mounts": self.mount_manager.list_mounts(),
+            "asgi_mount_count": len(self.mount_manager.mounts),
+        }
+
+    def cleanup(self) -> None:
+        logger.info("Cleaning up ASGI mounts")
+
+
 class ExtensionManager:
     def __init__(self) -> None:
         self.extensions: List[Extension] = []
@@ -145,7 +213,8 @@ class ExtensionManager:
             "routing": RoutingExtension,
             "security": SecurityExtension,
             "caching": CachingExtension,
-            "monitoring": MonitoringExtension
+            "monitoring": MonitoringExtension,
+            "asgi": ASGIExtension,
         }
 
     def register_extension_type(self, name: str, extension_class: Type[Extension]) -> None:

pyserve/server.py

@@ -10,7 +10,7 @@ from pathlib import Path
 from typing import Optional, Dict, Any
 
 from .config import Config
-from .extensions import ExtensionManager
+from .extensions import ExtensionManager, ASGIExtension
 from .logging_utils import get_logger
 from . import __version__
 
@@ -30,6 +30,11 @@ class PyServeMiddleware:
 
         start_time = time.time()
         request = Request(scope, receive)
+
+        asgi_handled = await self._try_asgi_mount(scope, receive, send, request, start_time)
+        if asgi_handled:
+            return
+
         response = await self.extension_manager.process_request(request)
 
         if response is None:
@@ -39,6 +44,68 @@ class PyServeMiddleware:
         response = await self.extension_manager.process_response(request, response)
         response.headers["Server"] = f"pyserve/{__version__}"
 
+        self._log_access(request, response, start_time)
+
+        await response(scope, receive, send)
+
+    async def _try_asgi_mount(
+        self,
+        scope: Scope,
+        receive: Receive,
+        send: Send,
+        request: Request,
+        start_time: float
+    ) -> bool:
+        for extension in self.extension_manager.extensions:
+            if isinstance(extension, ASGIExtension):
+                mount = extension.get_asgi_handler(request)
+                if mount is not None:
+                    modified_scope = dict(scope)
+                    if mount.strip_path:
+                        modified_scope["path"] = mount.get_modified_path(request.url.path)
+                        modified_scope["root_path"] = scope.get("root_path", "") + mount.path
+
+                    logger.debug(
+                        f"Routing to ASGI mount '{mount.name}': "
+                        f"{request.url.path} -> {modified_scope['path']}"
+                    )
+
+                    try:
+                        response_started = False
+                        status_code = 0
+
+                        async def send_wrapper(message: Dict[str, Any]) -> None:
+                            nonlocal response_started, status_code
+                            if message["type"] == "http.response.start":
+                                response_started = True
+                                status_code = message.get("status", 0)
+                            await send(message)
+
+                        await mount.app(modified_scope, receive, send_wrapper)
+
+                        process_time = round((time.time() - start_time) * 1000, 2)
+                        self.access_logger.info(
+                            "ASGI request",
+                            client_ip=request.client.host if request.client else "unknown",
+                            method=request.method,
+                            path=str(request.url.path),
+                            mount=mount.name,
+                            status_code=status_code,
+                            process_time_ms=process_time,
+                            user_agent=request.headers.get("user-agent", "")
+                        )
+                        return True
+                    except Exception as e:
+                        logger.error(f"Error in ASGI mount '{mount.name}': {e}")
+                        error_response = PlainTextResponse(
+                            "500 Internal Server Error",
+                            status_code=500
+                        )
+                        await error_response(scope, receive, send)
+                        return True
+        return False
+
+    def _log_access(self, request: Request, response: Response, start_time: float) -> None:
         client_ip = request.client.host if request.client else "unknown"
         method = request.method
         path = str(request.url.path)
@@ -58,8 +125,6 @@ class PyServeMiddleware:
             user_agent=request.headers.get("user-agent", "")
         )
 
-        await response(scope, receive, send)
-
 
 class PyServeServer:
     def __init__(self, config: Config):