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"""A patch to make async httpx work using JavaScript fetch."""
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from contextlib import contextmanager
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from httpx._client import AsyncClient, BoundAsyncStream, logger
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from httpx._models import Headers, Request, Response
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from httpx._transports.default import AsyncResponseStream
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from httpx._types import AsyncByteStream
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from httpx._utils import Timer
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from js import Headers as js_Headers
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from js import fetch
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from pyodide.ffi import create_proxy
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@contextmanager
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def acquire_buffer(content):
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    """Acquire a Uint8Array view of a bytes object"""
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    if not content:
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        yield None
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        return
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    body_px = create_proxy(content)
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    body_buf = body_px.getBuffer("u8")
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    try:
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        yield body_buf.data
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    finally:
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        body_px.destroy()
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        body_buf.release()
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async def js_readable_stream_iter(js_readable_stream):
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    """Readable streams are supposed to be async iterators some day but they
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    aren't yet. In the meantime, this is an adaptor that produces an async
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    iterator from a readable stream.
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    """
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    reader = js_readable_stream.getReader()
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    while True:
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        res = await reader.read()
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        if res.done:
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            return
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        b = res.value.to_bytes()
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        print("js_readable_stream_iter", b)
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        yield b
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async def _send_single_request(self, request: Request) -> Response:
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    """
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    Sends a single request, without handling any redirections.
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    This is the function we're patching here...
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    """
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    timer = Timer()
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    await timer.async_start()
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    if not isinstance(request.stream, AsyncByteStream):
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        raise TypeError(
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            "Attempted to send an sync request with an AsyncClient instance."
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        )
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    # BEGIN MODIFIED PART
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    js_headers = js_Headers.new(request.headers.multi_items())
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    with acquire_buffer(request.content) as body:
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        js_resp = await fetch(
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            str(request.url), method=request.method, headers=js_headers, body=body
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        )
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    py_headers = Headers(js_resp.headers)
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    # Unset content-encoding b/c Javascript fetch already handled unpacking. If
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    # we leave it we will get errors when httpx tries to unpack a second time.
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    py_headers.pop("content-encoding", None)
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    response = Response(
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        status_code=js_resp.status,
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        headers=py_headers,
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        stream=AsyncResponseStream(js_readable_stream_iter(js_resp.body)),
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    )
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    # END MODIFIED PART
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    assert isinstance(response.stream, AsyncByteStream)
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    response.request = request
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    response.stream = BoundAsyncStream(response.stream, response=response, timer=timer)
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    self.cookies.extract_cookies(response)
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    response.default_encoding = self._default_encoding
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    logger.info(
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        'HTTP Request: %s %s "%s %d %s"',
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        request.method,
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        request.url,
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        response.http_version,
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        response.status_code,
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        response.reason_phrase,
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    )
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    return response
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AsyncClient._send_single_request = _send_single_request