requests: Add readinto to BodyStream for mip compatibility.

BodyStream now implements readinto() so mip can stream downloads via
response.raw without allocating intermediate buffers.

Signed-off-by: Pablo Ventura <pablogventura@gmail.com>

Author: pablogventura

python-ecosys/requests/requests/__init__.py

@@ -17,6 +17,18 @@ def read(self, n=-1):
             raise ValueError("Connection closed before Content-Length satisfied")
         return data
 
+    def readinto(self, buf):
+        if self._remaining == 0:
+            return 0
+        n = len(buf)
+        if n > self._remaining:
+            n = self._remaining
+        got = self._sock.readinto(memoryview(buf)[:n])
+        self._remaining -= got
+        if not got:
+            raise ValueError("Connection closed before Content-Length satisfied")
+        return got
+
     def close(self):
         self._sock.close()
 

python-ecosys/requests/test_requests.py

@@ -19,6 +19,12 @@ def readline(self):
     def read(self, size=-1):
         return self._read_buffer.read(size)
 
+    def readinto(self, buf):
+        data = self._read_buffer.read(len(buf))
+        n = len(data)
+        buf[:n] = data
+        return n
+
     def close(self):
         pass
 
@@ -227,6 +233,22 @@ def test_raw_incremental_content_length():
     install_mock_socket()
 
 
+def test_raw_readinto_content_length():
+    socket.socket = lambda *a, **k: Socket(
+        read_data=b"HTTP/1.1 200 OK\r\nContent-Length: 10\r\n\r\nabcdefghij"
+    )
+    response = requests.request("GET", "http://example.com")
+    buf = bytearray(3)
+    result = b""
+    while True:
+        n = response.raw.readinto(buf)
+        if n == 0:
+            break
+        result += buf if n == 3 else buf[:n]
+    assert result == b"abcdefghij"
+    install_mock_socket()
+
+
 TESTS = (
     test_simple_get,
     test_get_auth,
@@ -241,6 +263,7 @@ def test_raw_incremental_content_length():
     test_chunked_response_raises,
     test_raw_open_before_content,
     test_raw_incremental_content_length,
+    test_raw_readinto_content_length,
 )