import asyncio from concurrent.futures import Executor, ProcessPoolExecutor from functools import partial import logging from aiohttp import web import black import click # This is used internally by tests to shut down the server prematurely _stop_signal = asyncio.Event() VERSION_HEADER = "X-Protocol-Version" LINE_LENGTH_HEADER = "X-Line-Length" PYTHON_VARIANT_HEADER = "X-Python-Variant" SKIP_STRING_NORMALIZATION_HEADER = "X-Skip-String-Normalization" SKIP_NUMERIC_UNDERSCORE_NORMALIZATION_HEADER = "X-Skip-Numeric-Underscore-Normalization" FAST_OR_SAFE_HEADER = "X-Fast-Or-Safe" @click.command(context_settings={"help_option_names": ["-h", "--help"]}) @click.option( "--bind-host", type=str, help="Address to bind the server to.", default="localhost" ) @click.option("--bind-port", type=int, help="Port to listen on", default=45484) @click.version_option(version=black.__version__) def main(bind_host: str, bind_port: int) -> None: logging.basicConfig(level=logging.INFO) app = make_app() ver = black.__version__ black.out(f"blackd version {ver} listening on {bind_host} port {bind_port}") web.run_app(app, host=bind_host, port=bind_port, handle_signals=True, print=None) def make_app() -> web.Application: app = web.Application() executor = ProcessPoolExecutor() app.add_routes([web.post("/", partial(handle, executor=executor))]) return app async def handle(request: web.Request, executor: Executor) -> web.Response: try: if request.headers.get(VERSION_HEADER, "1") != "1": return web.Response( status=501, text="This server only supports protocol version 1" ) try: line_length = int( request.headers.get(LINE_LENGTH_HEADER, black.DEFAULT_LINE_LENGTH) ) except ValueError: return web.Response(status=400, text="Invalid line length header value") py36 = False pyi = False if PYTHON_VARIANT_HEADER in request.headers: value = request.headers[PYTHON_VARIANT_HEADER] if value == "pyi": pyi = True else: try: major, *rest = value.split(".") if int(major) == 3 and len(rest) > 0: if int(rest[0]) >= 6: py36 = True except ValueError: return web.Response( status=400, text=f"Invalid value for {PYTHON_VARIANT_HEADER}" ) skip_string_normalization = bool( request.headers.get(SKIP_STRING_NORMALIZATION_HEADER, False) ) skip_numeric_underscore_normalization = bool( request.headers.get(SKIP_NUMERIC_UNDERSCORE_NORMALIZATION_HEADER, False) ) fast = False if request.headers.get(FAST_OR_SAFE_HEADER, "safe") == "fast": fast = True mode = black.FileMode.from_configuration( py36=py36, pyi=pyi, skip_string_normalization=skip_string_normalization, skip_numeric_underscore_normalization=skip_numeric_underscore_normalization, ) req_bytes = await request.content.read() charset = request.charset if request.charset is not None else "utf8" req_str = req_bytes.decode(charset) loop = asyncio.get_event_loop() formatted_str = await loop.run_in_executor( executor, partial( black.format_file_contents, req_str, line_length=line_length, fast=fast, mode=mode, ), ) return web.Response( content_type=request.content_type, charset=charset, text=formatted_str ) except black.NothingChanged: return web.Response(status=204) except black.InvalidInput as e: return web.Response(status=400, text=str(e)) except Exception as e: logging.exception("Exception during handling a request") return web.Response(status=500, text=str(e)) def patched_main() -> None: black.patch_click() main() if __name__ == "__main__": patched_main()