Fix backend fixture

Author: Archmonger

src/reactpy/testing/backend.py

@@ -2,13 +2,16 @@
 
 import asyncio
 import logging
-from contextlib import AsyncExitStack, suppress
+from collections.abc import Coroutine
+from contextlib import AsyncExitStack
+from threading import Thread
 from types import TracebackType
 from typing import Any, Callable
 from urllib.parse import urlencode, urlunparse
 
-from reactpy.asgi import default as default_server
-from reactpy.asgi.utils import find_available_port
+import uvicorn
+
+from reactpy.asgi.standalone import ReactPy
 from reactpy.config import REACTPY_TESTS_DEFAULT_TIMEOUT
 from reactpy.core.component import component
 from reactpy.core.hooks import use_callback, use_effect, use_state
@@ -17,7 +20,8 @@
     capture_reactpy_logs,
     list_logged_exceptions,
 )
-from reactpy.types import BackendType, ComponentConstructor
+from reactpy.testing.utils import find_available_port
+from reactpy.types import ComponentConstructor
 from reactpy.utils import Ref
 
 
@@ -39,11 +43,9 @@ class BackendFixture:
 
     def __init__(
         self,
+        app: Callable[..., Coroutine] | None = None,
         host: str = "127.0.0.1",
         port: int | None = None,
-        app: Any | None = None,
-        implementation: BackendType[Any] | None = None,
-        options: Any | None = None,
         timeout: float | None = None,
     ) -> None:
         self.host = host
@@ -52,14 +54,12 @@ def __init__(
         self.timeout = (
             REACTPY_TESTS_DEFAULT_TIMEOUT.current if timeout is None else timeout
         )
-
-        if app is not None and implementation is None:
-            msg = "If an application instance its corresponding server implementation must be provided too."
-            raise ValueError(msg)
-
-        self._app = app
-        self.implementation = implementation or default_server
-        self._options = options
+        self._app = app or ReactPy(self._root_component)
+        self.webserver = uvicorn.Server(
+            uvicorn.Config(
+                app=self._app, host=self.host, port=self.port, loop="asyncio"
+            )
+        )
 
     @property
     def log_records(self) -> list[logging.LogRecord]:
@@ -109,30 +109,7 @@ def list_logged_exceptions(
     async def __aenter__(self) -> BackendFixture:
         self._exit_stack = AsyncExitStack()
         self._records = self._exit_stack.enter_context(capture_reactpy_logs())
-
-        app = self._app or self.implementation.create_development_app()
-        self.implementation.configure(app, self._root_component, self._options)
-
-        started = asyncio.Event()
-        server_future = asyncio.create_task(
-            self.implementation.serve_development_app(
-                app, self.host, self.port, started
-            )
-        )
-
-        async def stop_server() -> None:
-            server_future.cancel()
-            with suppress(asyncio.CancelledError):
-                await asyncio.wait_for(server_future, timeout=self.timeout)
-
-        self._exit_stack.push_async_callback(stop_server)
-
-        try:
-            await asyncio.wait_for(started.wait(), timeout=self.timeout)
-        except Exception:  # nocov
-            # see if we can await the future for a more helpful error
-            await asyncio.wait_for(server_future, timeout=self.timeout)
-            raise
+        Thread(target=self.webserver.run, daemon=True).start()
 
         return self
 
@@ -151,6 +128,8 @@ async def __aexit__(
             msg = "Unexpected logged exception"
             raise LogAssertionError(msg) from logged_errors[0]
 
+        await asyncio.wait_for(self.webserver.shutdown(), timeout=5)
+
 
 _MountFunc = Callable[["Callable[[], Any] | None"], None]
 

src/reactpy/testing/display.py

@@ -26,7 +26,6 @@ def __init__(
         self,
         backend: BackendFixture | None = None,
         driver: Browser | BrowserContext | Page | None = None,
-        url_prefix: str = "",
     ) -> None:
         if backend is not None:
             self.backend = backend
@@ -35,7 +34,6 @@ def __init__(
                 self.page = driver
             else:
                 self._browser = driver
-        self.url_prefix = url_prefix
 
     async def show(
         self,
@@ -45,14 +43,8 @@ async def show(
         await self.goto("/")
         await self.root_element()  # check that root element is attached
 
-    async def goto(
-        self, path: str, query: Any | None = None, add_url_prefix: bool = True
-    ) -> None:
-        await self.page.goto(
-            self.backend.url(
-                f"{self.url_prefix}{path}" if add_url_prefix else path, query
-            )
-        )
+    async def goto(self, path: str, query: Any | None = None) -> None:
+        await self.page.goto(self.backend.url(path, query))
 
     async def root_element(self) -> ElementHandle:
         element = await self.page.wait_for_selector("#app", state="attached")

src/reactpy/testing/utils.py

@@ -0,0 +1,25 @@
+from __future__ import annotations
+
+import socket
+import sys
+from contextlib import closing
+
+
+def find_available_port(host: str, port_min: int = 8000, port_max: int = 9000) -> int:
+    """Get a port that's available for the given host and port range"""
+    for port in range(port_min, port_max):
+        with closing(socket.socket()) as sock:
+            try:
+                if sys.platform in ("linux", "darwin"):
+                    # Fixes bug on Unix-like systems where every time you restart the
+                    # server you'll get a different port on Linux. This cannot be set
+                    # on Windows otherwise address will always be reused.
+                    # Ref: https://stackoverflow.com/a/19247688/3159288
+                    sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+                sock.bind((host, port))
+            except OSError:
+                pass
+            else:
+                return port
+    msg = f"Host {host!r} has no available port in range {port_max}-{port_max}"
+    raise RuntimeError(msg)