1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
|
"""
Utility functions for decoding response bodies.
"""
from __future__ import absolute_import
from io import BytesIO
import gzip
import zlib
from .utils import always_byte_args
ENCODINGS = {b"identity", b"gzip", b"deflate"}
@always_byte_args("ascii", "ignore")
def decode(e, content):
encoding_map = {
b"identity": identity,
b"gzip": decode_gzip,
b"deflate": decode_deflate,
}
if e not in encoding_map:
return None
return encoding_map[e](content)
@always_byte_args("ascii", "ignore")
def encode(e, content):
encoding_map = {
b"identity": identity,
b"gzip": encode_gzip,
b"deflate": encode_deflate,
}
if e not in encoding_map:
return None
return encoding_map[e](content)
def identity(content):
"""
Returns content unchanged. Identity is the default value of
Accept-Encoding headers.
"""
return content
def decode_gzip(content):
gfile = gzip.GzipFile(fileobj=BytesIO(content))
try:
return gfile.read()
except (IOError, EOFError):
return None
def encode_gzip(content):
s = BytesIO()
gf = gzip.GzipFile(fileobj=s, mode='wb')
gf.write(content)
gf.close()
return s.getvalue()
def decode_deflate(content):
"""
Returns decompressed data for DEFLATE. Some servers may respond with
compressed data without a zlib header or checksum. An undocumented
feature of zlib permits the lenient decompression of data missing both
values.
http://bugs.python.org/issue5784
"""
try:
try:
return zlib.decompress(content)
except zlib.error:
return zlib.decompress(content, -15)
except zlib.error:
return None
def encode_deflate(content):
"""
Returns compressed content, always including zlib header and checksum.
"""
return zlib.compress(content)
__all__ = ["ENCODINGS", "encode", "decode"]
|
