implement connection context

Author: rmorshea

src/idom/__init__.py

@@ -17,7 +17,7 @@
 from .core.vdom import vdom
 from .server.utils import run
 from .utils import Ref, html_to_vdom
-from .widgets import hotswap, multiview
+from .widgets import hotswap
 
 
 __author__ = "idom-team"
@@ -34,7 +34,6 @@
     "html",
     "Layout",
     "log",
-    "multiview",
     "Ref",
     "run",
     "Stop",

src/idom/core/hooks.py

@@ -206,19 +206,19 @@ def effect() -> None:
 
 def create_context(
     default_value: _StateType, name: str | None = None
-) -> type[_Context[_StateType]]:
+) -> type[Context[_StateType]]:
     """Return a new context type for use in :func:`use_context`"""
 
-    class Context(_Context[_StateType]):
+    class _Context(Context[_StateType]):
         _default_value = default_value
 
     if name is not None:
-        Context.__name__ = name
+        _Context.__name__ = name
 
-    return Context
+    return _Context
 
 
-def use_context(context_type: type[_Context[_StateType]]) -> _StateType:
+def use_context(context_type: type[Context[_StateType]]) -> _StateType:
     """Get the current value for the given context type.
 
     See the full :ref:`Use Context` docs for more information.
@@ -228,7 +228,7 @@ def use_context(context_type: type[_Context[_StateType]]) -> _StateType:
     # that newly present current context. When we update it though, we don't need to
     # schedule a new render since we're already rending right now. Thus we can't do this
     # with use_state() since we'd incur an extra render when calling set_state.
-    context_ref: Ref[_Context[_StateType] | None] = use_ref(None)
+    context_ref: Ref[Context[_StateType] | None] = use_ref(None)
 
     if context_ref.current is None:
         provided_context = context_type._current.get()
@@ -244,7 +244,7 @@ def use_context(context_type: type[_Context[_StateType]]) -> _StateType:
 
     @use_effect
     def subscribe_to_context_change() -> Callable[[], None]:
-        def set_context(new: _Context[_StateType]) -> None:
+        def set_context(new: Context[_StateType]) -> None:
             # We don't need to check if `new is not context_ref.current` because we only
             # trigger this callback when the value of a context, and thus the context
             # itself changes. Therefore we can always schedule a render.
@@ -260,13 +260,13 @@ def set_context(new: _Context[_StateType]) -> None:
 _UNDEFINED: Any = object()
 
 
-class _Context(Generic[_StateType]):
+class Context(Generic[_StateType]):
 
     # This should be _StateType instead of Any, but it can't due to this limitation:
     # https://github.com/python/mypy/issues/5144
     _default_value: ClassVar[Any]
 
-    _current: ClassVar[ThreadLocal[_Context[Any] | None]]
+    _current: ClassVar[ThreadLocal[Context[Any] | None]]
 
     def __init_subclass__(cls) -> None:
         # every context type tracks which of its instances are currently in use
@@ -281,7 +281,7 @@ def __init__(
         self.children = children
         self.value: _StateType = self._default_value if value is _UNDEFINED else value
         self.key = key
-        self.subscribers: set[Callable[[_Context[_StateType]], None]] = set()
+        self.subscribers: set[Callable[[Context[_StateType]], None]] = set()
         self.type = self.__class__
 
     def render(self) -> VdomDict:
@@ -297,7 +297,7 @@ def reset_ctx() -> None:
 
         return vdom("", *self.children)
 
-    def should_render(self, new: _Context[_StateType]) -> bool:
+    def should_render(self, new: Context[_StateType]) -> bool:
         if self.value is not new.value:
             new.subscribers.update(self.subscribers)
             for set_context in self.subscribers:

src/idom/core/layout.py

@@ -193,6 +193,7 @@ def _render_component(
 
         if (
             old_state is not None
+            and hasattr(old_state.model, "current")
             and old_state.is_component_state
             and not _check_should_render(
                 old_state.life_cycle_state.component, component

src/idom/server/_conn.py

@@ -0,0 +1,9 @@
+from __future__ import annotations
+
+from typing import Any
+
+from idom.core.hooks import create_context
+from idom.types import Context
+
+
+Connection: type[Context[Any | None]] = create_context(None, name="Connection")

src/idom/server/default.py

@@ -28,6 +28,10 @@ async def serve_development_app(
     )
 
 
+def use_connection() -> Any:
+    return _default_implementation().use_connection()
+
+
 def _default_implementation() -> ServerImplementation[Any]:
     """Get the first available server implementation"""
     global _DEFAULT_IMPLEMENTATION

src/idom/server/fastapi.py

@@ -11,10 +11,16 @@
     _setup_options,
     _setup_single_view_dispatcher_route,
     serve_development_app,
+    use_connection,
 )
 
 
-__all__ = "configure", "serve_development_app", "create_development_app"
+__all__ = (
+    "configure",
+    "serve_development_app",
+    "create_development_app",
+    "use_connection",
+)
 
 
 def configure(

src/idom/server/flask.py

@@ -10,7 +10,16 @@
 from typing import Any, Callable, Dict, NamedTuple, Optional, Union, cast
 from urllib.parse import parse_qs as parse_query_string
 
-from flask import Blueprint, Flask, redirect, request, send_from_directory, url_for
+from flask import (
+    Blueprint,
+    Flask,
+    Request,
+    copy_current_request_context,
+    redirect,
+    request,
+    send_from_directory,
+    url_for,
+)
 from flask_cors import CORS
 from flask_sockets import Sockets
 from gevent import pywsgi
@@ -20,10 +29,12 @@
 
 import idom
 from idom.config import IDOM_WEB_MODULES_DIR
+from idom.core.hooks import use_context
 from idom.core.layout import LayoutEvent, LayoutUpdate
 from idom.core.serve import serve_json_patch
 from idom.core.types import ComponentType, RootComponentConstructor
 
+from ._conn import Connection
 from .utils import CLIENT_BUILD_DIR
 
 
@@ -94,6 +105,13 @@ def run_server():
             raise RuntimeError("Failed to shutdown server.")
 
 
+def use_connection() -> Request:
+    value = use_context(Connection)
+    if value is None:
+        raise RuntimeError("No established connection.")
+    return value
+
+
 class Options(TypedDict, total=False):
     """Render server config for :class:`FlaskRenderServer`"""
 
@@ -175,14 +193,7 @@ def recv() -> Optional[LayoutEvent]:
             else:
                 return None
 
-        dispatch_in_thread(constructor(**_get_query_params(ws)), send, recv)
-
-
-def _get_query_params(ws: WebSocket) -> Dict[str, Any]:
-    return {
-        k: v if len(v) > 1 else v[0]
-        for k, v in parse_query_string(ws.environ["QUERY_STRING"]).items()
-    }
+        dispatch_in_thread(constructor(), send, recv)
 
 
 def dispatch_in_thread(
@@ -193,6 +204,7 @@ def dispatch_in_thread(
     dispatch_thread_info_created = ThreadEvent()
     dispatch_thread_info_ref: idom.Ref[Optional[_DispatcherThreadInfo]] = idom.Ref(None)
 
+    @copy_current_request_context
     def run_dispatcher() -> None:
         loop = asyncio.new_event_loop()
         asyncio.set_event_loop(loop)
@@ -207,7 +219,9 @@ async def recv_coro() -> Any:
             return await async_recv_queue.get()
 
         async def main() -> None:
-            await serve_json_patch(idom.Layout(component), send_coro, recv_coro)
+            await serve_json_patch(
+                idom.Layout(Connection(component, value=request)), send_coro, recv_coro
+            )
 
         main_future = asyncio.ensure_future(main())
 

src/idom/server/sanic.py

@@ -22,6 +22,7 @@
 )
 from idom.core.types import RootComponentConstructor
 
+from ._conn import Connection
 from .utils import CLIENT_BUILD_DIR
 
 
@@ -63,6 +64,13 @@ async def serve_development_app(
         app.stop()
 
 
+def use_connection() -> request.Request:
+    value = use_connection(Connection)
+    if value is None:
+        raise RuntimeError("No established connection.")
+    return value
+
+
 class Options(TypedDict, total=False):
     """Options for :class:`SanicRenderServer`"""
 
@@ -122,7 +130,11 @@ async def model_stream(
     ) -> None:
         send, recv = _make_send_recv_callbacks(socket)
         component_params = {k: request.args.get(k) for k in request.args}
-        await serve_json_patch(Layout(constructor(**component_params)), send, recv)
+        await serve_json_patch(
+            Layout(Connection(constructor(**component_params), value=request)),
+            send,
+            recv,
+        )
 
 
 def _make_send_recv_callbacks(

src/idom/server/starlette.py

@@ -17,6 +17,7 @@
 from uvicorn.server import Server as UvicornServer
 
 from idom.config import IDOM_WEB_MODULES_DIR
+from idom.core.hooks import use_context
 from idom.core.layout import Layout, LayoutEvent
 from idom.core.serve import (
     RecvCoroutine,
@@ -27,6 +28,7 @@
 from idom.core.types import RootComponentConstructor
 
 from ._asgi import serve_development_asgi
+from ._conn import Connection
 from .utils import CLIENT_BUILD_DIR
 
 
@@ -67,6 +69,13 @@ async def serve_development_app(
     await serve_development_asgi(app, host, port, started)
 
 
+def use_connection() -> WebSocket:
+    value = use_context(Connection)
+    if value is None:
+        raise RuntimeError("No established connection.")
+    return value
+
+
 class Options(TypedDict, total=False):
     """Optionsuration options for :class:`StarletteRenderServer`"""
 
@@ -145,7 +154,9 @@ async def model_stream(socket: WebSocket) -> None:
         send, recv = _make_send_recv_callbacks(socket)
         try:
             await serve_json_patch(
-                Layout(constructor(**dict(socket.query_params))), send, recv
+                Layout(Connection(constructor(), value=socket)),
+                send,
+                recv,
             )
         except WebSocketDisconnect as error:
             logger.info(f"WebSocket disconnect: {error.code}")

src/idom/server/tornado.py

@@ -8,16 +8,19 @@
 from urllib.parse import urljoin
 
 from tornado.httpserver import HTTPServer
+from tornado.httputil import HTTPServerRequest
 from tornado.platform.asyncio import AsyncIOMainLoop
 from tornado.web import Application, RedirectHandler, RequestHandler, StaticFileHandler
 from tornado.websocket import WebSocketHandler
 from typing_extensions import TypedDict
 
 from idom.config import IDOM_WEB_MODULES_DIR
+from idom.core.hooks import use_context
 from idom.core.layout import Layout, LayoutEvent
 from idom.core.serve import VdomJsonPatch, serve_json_patch
 from idom.core.types import ComponentConstructor
 
+from ._conn import Connection
 from .utils import CLIENT_BUILD_DIR
 
 
@@ -69,6 +72,13 @@ async def serve_development_app(
         await server.close_all_connections()
 
 
+def use_connection() -> HTTPServerRequest:
+    value = use_context(Connection)
+    if value is None:
+        raise RuntimeError("No established connection.")
+    return value
+
+
 class Options(TypedDict, total=False):
     """Render server options for :class:`TornadoRenderServer` subclasses"""
 
@@ -160,7 +170,7 @@ async def recv() -> LayoutEvent:
         self._message_queue = message_queue
         self._dispatch_future = asyncio.ensure_future(
             serve_json_patch(
-                Layout(self._component_constructor(**query_params)),
+                Layout(Connection(self._component_constructor(), value=self.request)),
                 send,
                 recv,
             )