Issue #13464: Add a readinto() method to http.client.HTTPResponse.

Patch by Jon Kuhn.
This commit is contained in:
Antoine Pitrou 2011-12-06 22:33:57 +01:00
parent 0f6492250c
commit 38d9643d5e
5 changed files with 215 additions and 48 deletions

View File

@ -502,6 +502,12 @@ statement.
Reads and returns the response body, or up to the next *amt* bytes.
.. method:: HTTPResponse.readinto(b)
Reads up to the next len(b) bytes of the response body into the buffer *b*.
Returns the number of bytes read.
.. versionadded:: 3.3
.. method:: HTTPResponse.getheader(name, default=None)

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@ -485,11 +485,17 @@ class HTTPResponse(io.RawIOBase):
self.close()
return b""
if self.chunked:
return self._read_chunked(amt)
if amt is not None:
# Amount is given, so call base class version
# (which is implemented in terms of self.readinto)
return super(HTTPResponse, self).read(amt)
else:
# Amount is not given (unbounded read) so we must check self.length
# and self.chunked
if self.chunked:
return self._readall_chunked()
if amt is None:
# unbounded read
if self.length is None:
s = self.fp.read()
else:
@ -498,61 +504,49 @@ class HTTPResponse(io.RawIOBase):
self.close() # we read everything
return s
def readinto(self, b):
if self.fp is None:
return 0
if self._method == "HEAD":
self.close()
return 0
if self.chunked:
return self._readinto_chunked(b)
if self.length is not None:
if amt > self.length:
if len(b) > self.length:
# clip the read to the "end of response"
amt = self.length
b = memoryview(b)[0:self.length]
# we do not use _safe_read() here because this may be a .will_close
# connection, and the user is reading more bytes than will be provided
# (for example, reading in 1k chunks)
s = self.fp.read(amt)
n = self.fp.readinto(b)
if self.length is not None:
self.length -= len(s)
self.length -= n
if not self.length:
self.close()
return s
return n
def _read_chunked(self, amt):
assert self.chunked != _UNKNOWN
chunk_left = self.chunk_left
value = []
while True:
if chunk_left is None:
line = self.fp.readline(_MAXLINE + 1)
if len(line) > _MAXLINE:
raise LineTooLong("chunk size")
i = line.find(b";")
if i >= 0:
line = line[:i] # strip chunk-extensions
try:
chunk_left = int(line, 16)
except ValueError:
# close the connection as protocol synchronisation is
# probably lost
self.close()
raise IncompleteRead(b''.join(value))
if chunk_left == 0:
break
if amt is None:
value.append(self._safe_read(chunk_left))
elif amt < chunk_left:
value.append(self._safe_read(amt))
self.chunk_left = chunk_left - amt
return b''.join(value)
elif amt == chunk_left:
value.append(self._safe_read(amt))
self._safe_read(2) # toss the CRLF at the end of the chunk
self.chunk_left = None
return b''.join(value)
else:
value.append(self._safe_read(chunk_left))
amt -= chunk_left
# we read the whole chunk, get another
self._safe_read(2) # toss the CRLF at the end of the chunk
chunk_left = None
def _read_next_chunk_size(self):
# Read the next chunk size from the file
line = self.fp.readline(_MAXLINE + 1)
if len(line) > _MAXLINE:
raise LineTooLong("chunk size")
i = line.find(b";")
if i >= 0:
line = line[:i] # strip chunk-extensions
try:
return int(line, 16)
except ValueError:
# close the connection as protocol synchronisation is
# probably lost
self.close()
raise
def _read_and_discard_trailer(self):
# read and discard trailer up to the CRLF terminator
### note: we shouldn't have any trailers!
while True:
@ -566,11 +560,72 @@ class HTTPResponse(io.RawIOBase):
if line == b"\r\n":
break
def _readall_chunked(self):
assert self.chunked != _UNKNOWN
chunk_left = self.chunk_left
value = []
while True:
if chunk_left is None:
try:
chunk_left = self._read_next_chunk_size()
if chunk_left == 0:
break
except ValueError:
raise IncompleteRead(b''.join(value))
value.append(self._safe_read(chunk_left))
# we read the whole chunk, get another
self._safe_read(2) # toss the CRLF at the end of the chunk
chunk_left = None
self._read_and_discard_trailer()
# we read everything; close the "file"
self.close()
return b''.join(value)
def _readinto_chunked(self, b):
assert self.chunked != _UNKNOWN
chunk_left = self.chunk_left
total_bytes = 0
mvb = memoryview(b)
while True:
if chunk_left is None:
try:
chunk_left = self._read_next_chunk_size()
if chunk_left == 0:
break
except ValueError:
raise IncompleteRead(bytes(b[0:total_bytes]))
if len(mvb) < chunk_left:
n = self._safe_readinto(mvb)
self.chunk_left = chunk_left - n
return n
elif len(mvb) == chunk_left:
n = self._safe_readinto(mvb)
self._safe_read(2) # toss the CRLF at the end of the chunk
self.chunk_left = None
return n
else:
temp_mvb = mvb[0:chunk_left]
n = self._safe_readinto(temp_mvb)
mvb = mvb[n:]
total_bytes += n
# we read the whole chunk, get another
self._safe_read(2) # toss the CRLF at the end of the chunk
chunk_left = None
self._read_and_discard_trailer()
# we read everything; close the "file"
self.close()
return total_bytes
def _safe_read(self, amt):
"""Read the number of bytes requested, compensating for partial reads.
@ -594,6 +649,22 @@ class HTTPResponse(io.RawIOBase):
amt -= len(chunk)
return b"".join(s)
def _safe_readinto(self, b):
"""Same as _safe_read, but for reading into a buffer."""
total_bytes = 0
mvb = memoryview(b)
while total_bytes < len(b):
if MAXAMOUNT < len(mvb):
temp_mvb = mvb[0:MAXAMOUNT]
n = self.fp.readinto(temp_mvb)
else:
n = self.fp.readinto(mvb)
if not n:
raise IncompleteRead(bytes(mvb[0:total_bytes]), len(b))
mvb = mvb[n:]
total_bytes += n
return total_bytes
def fileno(self):
return self.fp.fileno()

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@ -158,6 +158,23 @@ class BasicTest(TestCase):
self.assertEqual(resp.read(2), b'xt')
self.assertTrue(resp.isclosed())
def test_partial_readintos(self):
# if we have a lenght, the system knows when to close itself
# same behaviour than when we read the whole thing with read()
body = "HTTP/1.1 200 Ok\r\nContent-Length: 4\r\n\r\nText"
sock = FakeSocket(body)
resp = client.HTTPResponse(sock)
resp.begin()
b = bytearray(2)
n = resp.readinto(b)
self.assertEqual(n, 2)
self.assertEqual(bytes(b), b'Te')
self.assertFalse(resp.isclosed())
n = resp.readinto(b)
self.assertEqual(n, 2)
self.assertEqual(bytes(b), b'xt')
self.assertTrue(resp.isclosed())
def test_host_port(self):
# Check invalid host_port
@ -206,6 +223,21 @@ class BasicTest(TestCase):
if resp.read():
self.fail("Did not expect response from HEAD request")
def test_readinto_head(self):
# Test that the library doesn't attempt to read any data
# from a HEAD request. (Tickles SF bug #622042.)
sock = FakeSocket(
'HTTP/1.1 200 OK\r\n'
'Content-Length: 14432\r\n'
'\r\n',
NoEOFStringIO)
resp = client.HTTPResponse(sock, method="HEAD")
resp.begin()
b = bytearray(5)
if resp.readinto(b) != 0:
self.fail("Did not expect response from HEAD request")
self.assertEqual(bytes(b), b'\x00'*5)
def test_send_file(self):
expected = (b'GET /foo HTTP/1.1\r\nHost: example.com\r\n'
b'Accept-Encoding: identity\r\nContent-Length:')
@ -285,6 +317,40 @@ class BasicTest(TestCase):
finally:
resp.close()
def test_readinto_chunked(self):
chunked_start = (
'HTTP/1.1 200 OK\r\n'
'Transfer-Encoding: chunked\r\n\r\n'
'a\r\n'
'hello worl\r\n'
'1\r\n'
'd\r\n'
)
sock = FakeSocket(chunked_start + '0\r\n')
resp = client.HTTPResponse(sock, method="GET")
resp.begin()
b = bytearray(16)
n = resp.readinto(b)
self.assertEqual(b[:11], b'hello world')
self.assertEqual(n, 11)
resp.close()
for x in ('', 'foo\r\n'):
sock = FakeSocket(chunked_start + x)
resp = client.HTTPResponse(sock, method="GET")
resp.begin()
try:
b = bytearray(16)
n = resp.readinto(b)
except client.IncompleteRead as i:
self.assertEqual(i.partial, b'hello world')
self.assertEqual(repr(i),'IncompleteRead(11 bytes read)')
self.assertEqual(str(i),'IncompleteRead(11 bytes read)')
else:
self.fail('IncompleteRead expected')
finally:
resp.close()
def test_chunked_head(self):
chunked_start = (
'HTTP/1.1 200 OK\r\n'
@ -302,6 +368,26 @@ class BasicTest(TestCase):
self.assertEqual(resp.reason, 'OK')
self.assertTrue(resp.isclosed())
def test_readinto_chunked_head(self):
chunked_start = (
'HTTP/1.1 200 OK\r\n'
'Transfer-Encoding: chunked\r\n\r\n'
'a\r\n'
'hello world\r\n'
'1\r\n'
'd\r\n'
)
sock = FakeSocket(chunked_start + '0\r\n')
resp = client.HTTPResponse(sock, method="HEAD")
resp.begin()
b = bytearray(5)
n = resp.readinto(b)
self.assertEqual(n, 0)
self.assertEqual(bytes(b), b'\x00'*5)
self.assertEqual(resp.status, 200)
self.assertEqual(resp.reason, 'OK')
self.assertTrue(resp.isclosed())
def test_negative_content_length(self):
sock = FakeSocket(
'HTTP/1.1 200 OK\r\nContent-Length: -1\r\n\r\nHello\r\n')

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@ -547,6 +547,7 @@ Hannu Krosing
Andrej Krpic
Ivan Krstić
Andrew Kuchling
Jon Kuhn
Vladimir Kushnir
Ross Lagerwall
Cameron Laird

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@ -406,6 +406,9 @@ Core and Builtins
Library
-------
- Issue #13464: Add a readinto() method to http.client.HTTPResponse. Patch
by Jon Kuhn.
- tarfile.py: Correctly detect bzip2 compressed streams with blocksizes
other than 900k.