--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/urllib3/contrib/emscripten/response.py	Sun May 05 23:32:17 2024 -0400
@@ -0,0 +1,276 @@
+from __future__ import annotations
+
+import json as _json
+import logging
+import typing
+from contextlib import contextmanager
+from dataclasses import dataclass
+from http.client import HTTPException as HTTPException
+from io import BytesIO, IOBase
+
+from ...exceptions import InvalidHeader, TimeoutError
+from ...response import BaseHTTPResponse
+from ...util.retry import Retry
+from .request import EmscriptenRequest
+
+if typing.TYPE_CHECKING:
+    from ..._base_connection import BaseHTTPConnection, BaseHTTPSConnection
+
+log = logging.getLogger(__name__)
+
+
+@dataclass
+class EmscriptenResponse:
+    status_code: int
+    headers: dict[str, str]
+    body: IOBase | bytes
+    request: EmscriptenRequest
+
+
+class EmscriptenHttpResponseWrapper(BaseHTTPResponse):
+    def __init__(
+        self,
+        internal_response: EmscriptenResponse,
+        url: str | None = None,
+        connection: BaseHTTPConnection | BaseHTTPSConnection | None = None,
+    ):
+        self._pool = None  # set by pool class
+        self._body = None
+        self._response = internal_response
+        self._url = url
+        self._connection = connection
+        self._closed = False
+        super().__init__(
+            headers=internal_response.headers,
+            status=internal_response.status_code,
+            request_url=url,
+            version=0,
+            reason="",
+            decode_content=True,
+        )
+        self.length_remaining = self._init_length(self._response.request.method)
+        self.length_is_certain = False
+
+    @property
+    def url(self) -> str | None:
+        return self._url
+
+    @url.setter
+    def url(self, url: str | None) -> None:
+        self._url = url
+
+    @property
+    def connection(self) -> BaseHTTPConnection | BaseHTTPSConnection | None:
+        return self._connection
+
+    @property
+    def retries(self) -> Retry | None:
+        return self._retries
+
+    @retries.setter
+    def retries(self, retries: Retry | None) -> None:
+        # Override the request_url if retries has a redirect location.
+        self._retries = retries
+
+    def stream(
+        self, amt: int | None = 2**16, decode_content: bool | None = None
+    ) -> typing.Generator[bytes, None, None]:
+        """
+        A generator wrapper for the read() method. A call will block until
+        ``amt`` bytes have been read from the connection or until the
+        connection is closed.
+
+        :param amt:
+            How much of the content to read. The generator will return up to
+            much data per iteration, but may return less. This is particularly
+            likely when using compressed data. However, the empty string will
+            never be returned.
+
+        :param decode_content:
+            If True, will attempt to decode the body based on the
+            'content-encoding' header.
+        """
+        while True:
+            data = self.read(amt=amt, decode_content=decode_content)
+
+            if data:
+                yield data
+            else:
+                break
+
+    def _init_length(self, request_method: str | None) -> int | None:
+        length: int | None
+        content_length: str | None = self.headers.get("content-length")
+
+        if content_length is not None:
+            try:
+                # RFC 7230 section 3.3.2 specifies multiple content lengths can
+                # be sent in a single Content-Length header
+                # (e.g. Content-Length: 42, 42). This line ensures the values
+                # are all valid ints and that as long as the `set` length is 1,
+                # all values are the same. Otherwise, the header is invalid.
+                lengths = {int(val) for val in content_length.split(",")}
+                if len(lengths) > 1:
+                    raise InvalidHeader(
+                        "Content-Length contained multiple "
+                        "unmatching values (%s)" % content_length
+                    )
+                length = lengths.pop()
+            except ValueError:
+                length = None
+            else:
+                if length < 0:
+                    length = None
+
+        else:  # if content_length is None
+            length = None
+
+        # Check for responses that shouldn't include a body
+        if (
+            self.status in (204, 304)
+            or 100 <= self.status < 200
+            or request_method == "HEAD"
+        ):
+            length = 0
+
+        return length
+
+    def read(
+        self,
+        amt: int | None = None,
+        decode_content: bool | None = None,  # ignored because browser decodes always
+        cache_content: bool = False,
+    ) -> bytes:
+        if (
+            self._closed
+            or self._response is None
+            or (isinstance(self._response.body, IOBase) and self._response.body.closed)
+        ):
+            return b""
+
+        with self._error_catcher():
+            # body has been preloaded as a string by XmlHttpRequest
+            if not isinstance(self._response.body, IOBase):
+                self.length_remaining = len(self._response.body)
+                self.length_is_certain = True
+                # wrap body in IOStream
+                self._response.body = BytesIO(self._response.body)
+            if amt is not None:
+                # don't cache partial content
+                cache_content = False
+                data = self._response.body.read(amt)
+                if self.length_remaining is not None:
+                    self.length_remaining = max(self.length_remaining - len(data), 0)
+                if (self.length_is_certain and self.length_remaining == 0) or len(
+                    data
+                ) < amt:
+                    # definitely finished reading, close response stream
+                    self._response.body.close()
+                return typing.cast(bytes, data)
+            else:  # read all we can (and cache it)
+                data = self._response.body.read()
+                if cache_content:
+                    self._body = data
+                if self.length_remaining is not None:
+                    self.length_remaining = max(self.length_remaining - len(data), 0)
+                if len(data) == 0 or (
+                    self.length_is_certain and self.length_remaining == 0
+                ):
+                    # definitely finished reading, close response stream
+                    self._response.body.close()
+                return typing.cast(bytes, data)
+
+    def read_chunked(
+        self,
+        amt: int | None = None,
+        decode_content: bool | None = None,
+    ) -> typing.Generator[bytes, None, None]:
+        # chunked is handled by browser
+        while True:
+            bytes = self.read(amt, decode_content)
+            if not bytes:
+                break
+            yield bytes
+
+    def release_conn(self) -> None:
+        if not self._pool or not self._connection:
+            return None
+
+        self._pool._put_conn(self._connection)
+        self._connection = None
+
+    def drain_conn(self) -> None:
+        self.close()
+
+    @property
+    def data(self) -> bytes:
+        if self._body:
+            return self._body
+        else:
+            return self.read(cache_content=True)
+
+    def json(self) -> typing.Any:
+        """
+        Parses the body of the HTTP response as JSON.
+
+        To use a custom JSON decoder pass the result of :attr:`HTTPResponse.data` to the decoder.
+
+        This method can raise either `UnicodeDecodeError` or `json.JSONDecodeError`.
+
+        Read more :ref:`here <json>`.
+        """
+        data = self.data.decode("utf-8")
+        return _json.loads(data)
+
+    def close(self) -> None:
+        if not self._closed:
+            if isinstance(self._response.body, IOBase):
+                self._response.body.close()
+            if self._connection:
+                self._connection.close()
+                self._connection = None
+            self._closed = True
+
+    @contextmanager
+    def _error_catcher(self) -> typing.Generator[None, None, None]:
+        """
+        Catch Emscripten specific exceptions thrown by fetch.py,
+        instead re-raising urllib3 variants, so that low-level exceptions
+        are not leaked in the high-level api.
+
+        On exit, release the connection back to the pool.
+        """
+        from .fetch import _RequestError, _TimeoutError  # avoid circular import
+
+        clean_exit = False
+
+        try:
+            yield
+            # If no exception is thrown, we should avoid cleaning up
+            # unnecessarily.
+            clean_exit = True
+        except _TimeoutError as e:
+            raise TimeoutError(str(e))
+        except _RequestError as e:
+            raise HTTPException(str(e))
+        finally:
+            # If we didn't terminate cleanly, we need to throw away our
+            # connection.
+            if not clean_exit:
+                # The response may not be closed but we're not going to use it
+                # anymore so close it now
+                if (
+                    isinstance(self._response.body, IOBase)
+                    and not self._response.body.closed
+                ):
+                    self._response.body.close()
+                # release the connection back to the pool
+                self.release_conn()
+            else:
+                # If we have read everything from the response stream,
+                # return the connection back to the pool.
+                if (
+                    isinstance(self._response.body, IOBase)
+                    and self._response.body.closed
+                ):
+                    self.release_conn()