1 """Miscellaneous WSGI-related Utilities""" 2 3 import posixpath 4 5 __all__ = [ 6 'FileWrapper', 'guess_scheme', 'application_uri', 'request_uri', 7 'shift_path_info', 'setup_testing_defaults', 8 ] 9 10 11 class FileWrapper: 12 """Wrapper to convert file-like objects to iterables""" 13 14 def __init__(self, filelike, blksize=8192): 15 self.filelike = filelike 16 self.blksize = blksize 17 if hasattr(filelike,'close'): 18 self.close = filelike.close 19 20 def __getitem__(self,key): 21 data = self.filelike.read(self.blksize) 22 if data: 23 return data 24 raise IndexError 25 26 def __iter__(self): 27 return self 28 29 def next(self): 30 data = self.filelike.read(self.blksize) 31 if data: 32 return data 33 raise StopIteration 34 35 def guess_scheme(environ): 36 """Return a guess for whether 'wsgi.url_scheme' should be 'http' or 'https' 37 """ 38 if environ.get("HTTPS") in ('yes','on','1'): 39 return 'https' 40 else: 41 return 'http' 42 43 def application_uri(environ): 44 """Return the application's base URI (no PATH_INFO or QUERY_STRING)""" 45 url = environ['wsgi.url_scheme']+'://' 46 from urllib import quote 47 48 if environ.get('HTTP_HOST'): 49 url += environ['HTTP_HOST'] 50 else: 51 url += environ['SERVER_NAME'] 52 53 if environ['wsgi.url_scheme'] == 'https': 54 if environ['SERVER_PORT'] != '443': 55 url += ':' + environ['SERVER_PORT'] 56 else: 57 if environ['SERVER_PORT'] != '80': 58 url += ':' + environ['SERVER_PORT'] 59 60 url += quote(environ.get('SCRIPT_NAME') or '/') 61 return url 62 63 def request_uri(environ, include_query=1): 64 """Return the full request URI, optionally including the query string""" 65 url = application_uri(environ) 66 from urllib import quote 67 path_info = quote(environ.get('PATH_INFO',''),safe='/;=,') 68 if not environ.get('SCRIPT_NAME'): 69 url += path_info[1:] 70 else: 71 url += path_info 72 if include_query and environ.get('QUERY_STRING'): 73 url += '?' + environ['QUERY_STRING'] 74 return url 75 76 def shift_path_info(environ): 77 """Shift a name from PATH_INFO to SCRIPT_NAME, returning it 78 79 If there are no remaining path segments in PATH_INFO, return None. 80 Note: 'environ' is modified in-place; use a copy if you need to keep 81 the original PATH_INFO or SCRIPT_NAME. 82 83 Note: when PATH_INFO is just a '/', this returns '' and appends a trailing 84 '/' to SCRIPT_NAME, even though empty path segments are normally ignored, 85 and SCRIPT_NAME doesn't normally end in a '/'. This is intentional 86 behavior, to ensure that an application can tell the difference between 87 '/x' and '/x/' when traversing to objects. 88 """ 89 path_info = environ.get('PATH_INFO','') 90 if not path_info: 91 return None 92 93 path_parts = path_info.split('/') 94 path_parts[1:-1] = [p for p in path_parts[1:-1] if p and p != '.'] 95 name = path_parts[1] 96 del path_parts[1] 97 98 script_name = environ.get('SCRIPT_NAME','') 99 script_name = posixpath.normpath(script_name+'/'+name) 100 if script_name.endswith('/'): 101 script_name = script_name[:-1] 102 if not name and not script_name.endswith('/'): 103 script_name += '/' 104 105 environ['SCRIPT_NAME'] = script_name 106 environ['PATH_INFO'] = '/'.join(path_parts) 107 108 # Special case: '/.' on PATH_INFO doesn't get stripped, 109 # because we don't strip the last element of PATH_INFO 110 # if there's only one path part left. Instead of fixing this 111 # above, we fix it here so that PATH_INFO gets normalized to 112 # an empty string in the environ. 113 if name=='.': 114 name = None 115 return name 116 117 def setup_testing_defaults(environ): 118 """Update 'environ' with trivial defaults for testing purposes 119 120 This adds various parameters required for WSGI, including HTTP_HOST, 121 SERVER_NAME, SERVER_PORT, REQUEST_METHOD, SCRIPT_NAME, PATH_INFO, 122 and all of the wsgi.* variables. It only supplies default values, 123 and does not replace any existing settings for these variables. 124 125 This routine is intended to make it easier for unit tests of WSGI 126 servers and applications to set up dummy environments. It should *not* 127 be used by actual WSGI servers or applications, since the data is fake! 128 """ 129 130 environ.setdefault('SERVER_NAME','127.0.0.1') 131 environ.setdefault('SERVER_PROTOCOL','HTTP/1.0') 132 133 environ.setdefault('HTTP_HOST',environ['SERVER_NAME']) 134 environ.setdefault('REQUEST_METHOD','GET') 135 136 if 'SCRIPT_NAME' not in environ and 'PATH_INFO' not in environ: 137 environ.setdefault('SCRIPT_NAME','') 138 environ.setdefault('PATH_INFO','/') 139 140 environ.setdefault('wsgi.version', (1,0)) 141 environ.setdefault('wsgi.run_once', 0) 142 environ.setdefault('wsgi.multithread', 0) 143 environ.setdefault('wsgi.multiprocess', 0) 144 145 from StringIO import StringIO 146 environ.setdefault('wsgi.input', StringIO("")) 147 environ.setdefault('wsgi.errors', StringIO()) 148 environ.setdefault('wsgi.url_scheme',guess_scheme(environ)) 149 150 if environ['wsgi.url_scheme']=='http': 151 environ.setdefault('SERVER_PORT', '80') 152 elif environ['wsgi.url_scheme']=='https': 153 environ.setdefault('SERVER_PORT', '443') 154 155 156 157 _hoppish = { 158 'connection':1, 'keep-alive':1, 'proxy-authenticate':1, 159 'proxy-authorization':1, 'te':1, 'trailers':1, 'transfer-encoding':1, 160 'upgrade':1 161 }.__contains__ 162 163 def is_hop_by_hop(header_name): 164 """Return true if 'header_name' is an HTTP/1.1 "Hop-by-Hop" header""" 165 return _hoppish(header_name.lower()) 166
