Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/urllib3/util/request.py: 55%

1from __future__ import absolute_import 

2 

3from base64 import b64encode 

4 

5from ..exceptions import UnrewindableBodyError 

6from ..packages.six import b, integer_types 

7 

8# Pass as a value within ``headers`` to skip 

9# emitting some HTTP headers that are added automatically. 

10# The only headers that are supported are ``Accept-Encoding``, 

11# ``Host``, and ``User-Agent``. 

12SKIP_HEADER = "@@@SKIP_HEADER@@@" 

13SKIPPABLE_HEADERS = frozenset(["accept-encoding", "host", "user-agent"]) 

14 

15ACCEPT_ENCODING = "gzip,deflate" 

16try: 

17 try: 

18 import brotlicffi as _unused_module_brotli # noqa: F401 

19 except ImportError: 

20 import brotli as _unused_module_brotli # noqa: F401 

21except ImportError: 

22 pass 

23else: 

24 ACCEPT_ENCODING += ",br" 

25 

26_FAILEDTELL = object() 

27 

28 

29def make_headers( 

30 keep_alive=None, 

31 accept_encoding=None, 

32 user_agent=None, 

33 basic_auth=None, 

34 proxy_basic_auth=None, 

35 disable_cache=None, 

36): 

37 """ 

38 Shortcuts for generating request headers. 

39 

40 :param keep_alive: 

41 If ``True``, adds 'connection: keep-alive' header. 

42 

43 :param accept_encoding: 

44 Can be a boolean, list, or string. 

45 ``True`` translates to 'gzip,deflate'. 

46 List will get joined by comma. 

47 String will be used as provided. 

48 

49 :param user_agent: 

50 String representing the user-agent you want, such as 

51 "python-urllib3/0.6" 

52 

53 :param basic_auth: 

54 Colon-separated username:password string for 'authorization: basic ...' 

55 auth header. 

56 

57 :param proxy_basic_auth: 

58 Colon-separated username:password string for 'proxy-authorization: basic ...' 

59 auth header. 

60 

61 :param disable_cache: 

62 If ``True``, adds 'cache-control: no-cache' header. 

63 

64 Example:: 

65 

66 >>> make_headers(keep_alive=True, user_agent="Batman/1.0") 

67 {'connection': 'keep-alive', 'user-agent': 'Batman/1.0'} 

68 >>> make_headers(accept_encoding=True) 

69 {'accept-encoding': 'gzip,deflate'} 

70 """ 

71 headers = {} 

72 if accept_encoding: 

73 if isinstance(accept_encoding, str): 

74 pass 

75 elif isinstance(accept_encoding, list): 

76 accept_encoding = ",".join(accept_encoding) 

77 else: 

78 accept_encoding = ACCEPT_ENCODING 

79 headers["accept-encoding"] = accept_encoding 

80 

81 if user_agent: 

82 headers["user-agent"] = user_agent 

83 

84 if keep_alive: 

85 headers["connection"] = "keep-alive" 

86 

87 if basic_auth: 

88 headers["authorization"] = "Basic " + b64encode(b(basic_auth)).decode("utf-8") 

89 

90 if proxy_basic_auth: 

91 headers["proxy-authorization"] = "Basic " + b64encode( 

92 b(proxy_basic_auth) 

93 ).decode("utf-8") 

94 

95 if disable_cache: 

96 headers["cache-control"] = "no-cache" 

97 

98 return headers 

99 

100 

101def set_file_position(body, pos): 

102 """ 

103 If a position is provided, move file to that point. 

104 Otherwise, we'll attempt to record a position for future use. 

105 """ 

106 if pos is not None: 

107 rewind_body(body, pos) 

108 elif getattr(body, "tell", None) is not None: 

109 try: 

110 pos = body.tell() 

111 except (IOError, OSError): 

112 # This differentiates from None, allowing us to catch 

113 # a failed `tell()` later when trying to rewind the body. 

114 pos = _FAILEDTELL 

115 

116 return pos 

117 

118 

119def rewind_body(body, body_pos): 

120 """ 

121 Attempt to rewind body to a certain position. 

122 Primarily used for request redirects and retries. 

123 

124 :param body: 

125 File-like object that supports seek. 

126 

127 :param int pos: 

128 Position to seek to in file. 

129 """ 

130 body_seek = getattr(body, "seek", None) 

131 if body_seek is not None and isinstance(body_pos, integer_types): 

132 try: 

133 body_seek(body_pos) 

134 except (IOError, OSError): 

135 raise UnrewindableBodyError( 

136 "An error occurred when rewinding request body for redirect/retry." 

137 ) 

138 elif body_pos is _FAILEDTELL: 

139 raise UnrewindableBodyError( 

140 "Unable to record file position for rewinding " 

141 "request body during a redirect/retry." 

142 ) 

143 else: 

144 raise ValueError( 

145 "body_pos must be of type integer, instead it was %s." % type(body_pos) 

146 )