--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/python-win32-2.6.1/lib/wsgiref/validate.py Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,432 @@
+# (c) 2005 Ian Bicking and contributors; written for Paste (http://pythonpaste.org)
+# Licensed under the MIT license: http://www.opensource.org/licenses/mit-license.php
+# Also licenced under the Apache License, 2.0: http://opensource.org/licenses/apache2.0.php
+# Licensed to PSF under a Contributor Agreement
+"""
+Middleware to check for obedience to the WSGI specification.
+
+Some of the things this checks:
+
+* Signature of the application and start_response (including that
+ keyword arguments are not used).
+
+* Environment checks:
+
+ - Environment is a dictionary (and not a subclass).
+
+ - That all the required keys are in the environment: REQUEST_METHOD,
+ SERVER_NAME, SERVER_PORT, wsgi.version, wsgi.input, wsgi.errors,
+ wsgi.multithread, wsgi.multiprocess, wsgi.run_once
+
+ - That HTTP_CONTENT_TYPE and HTTP_CONTENT_LENGTH are not in the
+ environment (these headers should appear as CONTENT_LENGTH and
+ CONTENT_TYPE).
+
+ - Warns if QUERY_STRING is missing, as the cgi module acts
+ unpredictably in that case.
+
+ - That CGI-style variables (that don't contain a .) have
+ (non-unicode) string values
+
+ - That wsgi.version is a tuple
+
+ - That wsgi.url_scheme is 'http' or 'https' (@@: is this too
+ restrictive?)
+
+ - Warns if the REQUEST_METHOD is not known (@@: probably too
+ restrictive).
+
+ - That SCRIPT_NAME and PATH_INFO are empty or start with /
+
+ - That at least one of SCRIPT_NAME or PATH_INFO are set.
+
+ - That CONTENT_LENGTH is a positive integer.
+
+ - That SCRIPT_NAME is not '/' (it should be '', and PATH_INFO should
+ be '/').
+
+ - That wsgi.input has the methods read, readline, readlines, and
+ __iter__
+
+ - That wsgi.errors has the methods flush, write, writelines
+
+* The status is a string, contains a space, starts with an integer,
+ and that integer is in range (> 100).
+
+* That the headers is a list (not a subclass, not another kind of
+ sequence).
+
+* That the items of the headers are tuples of strings.
+
+* That there is no 'status' header (that is used in CGI, but not in
+ WSGI).
+
+* That the headers don't contain newlines or colons, end in _ or -, or
+ contain characters codes below 037.
+
+* That Content-Type is given if there is content (CGI often has a
+ default content type, but WSGI does not).
+
+* That no Content-Type is given when there is no content (@@: is this
+ too restrictive?)
+
+* That the exc_info argument to start_response is a tuple or None.
+
+* That all calls to the writer are with strings, and no other methods
+ on the writer are accessed.
+
+* That wsgi.input is used properly:
+
+ - .read() is called with zero or one argument
+
+ - That it returns a string
+
+ - That readline, readlines, and __iter__ return strings
+
+ - That .close() is not called
+
+ - No other methods are provided
+
+* That wsgi.errors is used properly:
+
+ - .write() and .writelines() is called with a string
+
+ - That .close() is not called, and no other methods are provided.
+
+* The response iterator:
+
+ - That it is not a string (it should be a list of a single string; a
+ string will work, but perform horribly).
+
+ - That .next() returns a string
+
+ - That the iterator is not iterated over until start_response has
+ been called (that can signal either a server or application
+ error).
+
+ - That .close() is called (doesn't raise exception, only prints to
+ sys.stderr, because we only know it isn't called when the object
+ is garbage collected).
+"""
+__all__ = ['validator']
+
+
+import re
+import sys
+from types import DictType, StringType, TupleType, ListType
+import warnings
+
+header_re = re.compile(r'^[a-zA-Z][a-zA-Z0-9\-_]*$')
+bad_header_value_re = re.compile(r'[\000-\037]')
+
+class WSGIWarning(Warning):
+ """
+ Raised in response to WSGI-spec-related warnings
+ """
+
+def assert_(cond, *args):
+ if not cond:
+ raise AssertionError(*args)
+
+def validator(application):
+
+ """
+ When applied between a WSGI server and a WSGI application, this
+ middleware will check for WSGI compliancy on a number of levels.
+ This middleware does not modify the request or response in any
+ way, but will throw an AssertionError if anything seems off
+ (except for a failure to close the application iterator, which
+ will be printed to stderr -- there's no way to throw an exception
+ at that point).
+ """
+
+ def lint_app(*args, **kw):
+ assert_(len(args) == 2, "Two arguments required")
+ assert_(not kw, "No keyword arguments allowed")
+ environ, start_response = args
+
+ check_environ(environ)
+
+ # We use this to check if the application returns without
+ # calling start_response:
+ start_response_started = []
+
+ def start_response_wrapper(*args, **kw):
+ assert_(len(args) == 2 or len(args) == 3, (
+ "Invalid number of arguments: %s" % (args,)))
+ assert_(not kw, "No keyword arguments allowed")
+ status = args[0]
+ headers = args[1]
+ if len(args) == 3:
+ exc_info = args[2]
+ else:
+ exc_info = None
+
+ check_status(status)
+ check_headers(headers)
+ check_content_type(status, headers)
+ check_exc_info(exc_info)
+
+ start_response_started.append(None)
+ return WriteWrapper(start_response(*args))
+
+ environ['wsgi.input'] = InputWrapper(environ['wsgi.input'])
+ environ['wsgi.errors'] = ErrorWrapper(environ['wsgi.errors'])
+
+ iterator = application(environ, start_response_wrapper)
+ assert_(iterator is not None and iterator != False,
+ "The application must return an iterator, if only an empty list")
+
+ check_iterator(iterator)
+
+ return IteratorWrapper(iterator, start_response_started)
+
+ return lint_app
+
+class InputWrapper:
+
+ def __init__(self, wsgi_input):
+ self.input = wsgi_input
+
+ def read(self, *args):
+ assert_(len(args) <= 1)
+ v = self.input.read(*args)
+ assert_(type(v) is type(""))
+ return v
+
+ def readline(self):
+ v = self.input.readline()
+ assert_(type(v) is type(""))
+ return v
+
+ def readlines(self, *args):
+ assert_(len(args) <= 1)
+ lines = self.input.readlines(*args)
+ assert_(type(lines) is type([]))
+ for line in lines:
+ assert_(type(line) is type(""))
+ return lines
+
+ def __iter__(self):
+ while 1:
+ line = self.readline()
+ if not line:
+ return
+ yield line
+
+ def close(self):
+ assert_(0, "input.close() must not be called")
+
+class ErrorWrapper:
+
+ def __init__(self, wsgi_errors):
+ self.errors = wsgi_errors
+
+ def write(self, s):
+ assert_(type(s) is type(""))
+ self.errors.write(s)
+
+ def flush(self):
+ self.errors.flush()
+
+ def writelines(self, seq):
+ for line in seq:
+ self.write(line)
+
+ def close(self):
+ assert_(0, "errors.close() must not be called")
+
+class WriteWrapper:
+
+ def __init__(self, wsgi_writer):
+ self.writer = wsgi_writer
+
+ def __call__(self, s):
+ assert_(type(s) is type(""))
+ self.writer(s)
+
+class PartialIteratorWrapper:
+
+ def __init__(self, wsgi_iterator):
+ self.iterator = wsgi_iterator
+
+ def __iter__(self):
+ # We want to make sure __iter__ is called
+ return IteratorWrapper(self.iterator, None)
+
+class IteratorWrapper:
+
+ def __init__(self, wsgi_iterator, check_start_response):
+ self.original_iterator = wsgi_iterator
+ self.iterator = iter(wsgi_iterator)
+ self.closed = False
+ self.check_start_response = check_start_response
+
+ def __iter__(self):
+ return self
+
+ def next(self):
+ assert_(not self.closed,
+ "Iterator read after closed")
+ v = self.iterator.next()
+ if self.check_start_response is not None:
+ assert_(self.check_start_response,
+ "The application returns and we started iterating over its body, but start_response has not yet been called")
+ self.check_start_response = None
+ return v
+
+ def close(self):
+ self.closed = True
+ if hasattr(self.original_iterator, 'close'):
+ self.original_iterator.close()
+
+ def __del__(self):
+ if not self.closed:
+ sys.stderr.write(
+ "Iterator garbage collected without being closed")
+ assert_(self.closed,
+ "Iterator garbage collected without being closed")
+
+def check_environ(environ):
+ assert_(type(environ) is DictType,
+ "Environment is not of the right type: %r (environment: %r)"
+ % (type(environ), environ))
+
+ for key in ['REQUEST_METHOD', 'SERVER_NAME', 'SERVER_PORT',
+ 'wsgi.version', 'wsgi.input', 'wsgi.errors',
+ 'wsgi.multithread', 'wsgi.multiprocess',
+ 'wsgi.run_once']:
+ assert_(key in environ,
+ "Environment missing required key: %r" % (key,))
+
+ for key in ['HTTP_CONTENT_TYPE', 'HTTP_CONTENT_LENGTH']:
+ assert_(key not in environ,
+ "Environment should not have the key: %s "
+ "(use %s instead)" % (key, key[5:]))
+
+ if 'QUERY_STRING' not in environ:
+ warnings.warn(
+ 'QUERY_STRING is not in the WSGI environment; the cgi '
+ 'module will use sys.argv when this variable is missing, '
+ 'so application errors are more likely',
+ WSGIWarning)
+
+ for key in environ.keys():
+ if '.' in key:
+ # Extension, we don't care about its type
+ continue
+ assert_(type(environ[key]) is StringType,
+ "Environmental variable %s is not a string: %r (value: %r)"
+ % (key, type(environ[key]), environ[key]))
+
+ assert_(type(environ['wsgi.version']) is TupleType,
+ "wsgi.version should be a tuple (%r)" % (environ['wsgi.version'],))
+ assert_(environ['wsgi.url_scheme'] in ('http', 'https'),
+ "wsgi.url_scheme unknown: %r" % environ['wsgi.url_scheme'])
+
+ check_input(environ['wsgi.input'])
+ check_errors(environ['wsgi.errors'])
+
+ # @@: these need filling out:
+ if environ['REQUEST_METHOD'] not in (
+ 'GET', 'HEAD', 'POST', 'OPTIONS','PUT','DELETE','TRACE'):
+ warnings.warn(
+ "Unknown REQUEST_METHOD: %r" % environ['REQUEST_METHOD'],
+ WSGIWarning)
+
+ assert_(not environ.get('SCRIPT_NAME')
+ or environ['SCRIPT_NAME'].startswith('/'),
+ "SCRIPT_NAME doesn't start with /: %r" % environ['SCRIPT_NAME'])
+ assert_(not environ.get('PATH_INFO')
+ or environ['PATH_INFO'].startswith('/'),
+ "PATH_INFO doesn't start with /: %r" % environ['PATH_INFO'])
+ if environ.get('CONTENT_LENGTH'):
+ assert_(int(environ['CONTENT_LENGTH']) >= 0,
+ "Invalid CONTENT_LENGTH: %r" % environ['CONTENT_LENGTH'])
+
+ if not environ.get('SCRIPT_NAME'):
+ assert_(environ.has_key('PATH_INFO'),
+ "One of SCRIPT_NAME or PATH_INFO are required (PATH_INFO "
+ "should at least be '/' if SCRIPT_NAME is empty)")
+ assert_(environ.get('SCRIPT_NAME') != '/',
+ "SCRIPT_NAME cannot be '/'; it should instead be '', and "
+ "PATH_INFO should be '/'")
+
+def check_input(wsgi_input):
+ for attr in ['read', 'readline', 'readlines', '__iter__']:
+ assert_(hasattr(wsgi_input, attr),
+ "wsgi.input (%r) doesn't have the attribute %s"
+ % (wsgi_input, attr))
+
+def check_errors(wsgi_errors):
+ for attr in ['flush', 'write', 'writelines']:
+ assert_(hasattr(wsgi_errors, attr),
+ "wsgi.errors (%r) doesn't have the attribute %s"
+ % (wsgi_errors, attr))
+
+def check_status(status):
+ assert_(type(status) is StringType,
+ "Status must be a string (not %r)" % status)
+ # Implicitly check that we can turn it into an integer:
+ status_code = status.split(None, 1)[0]
+ assert_(len(status_code) == 3,
+ "Status codes must be three characters: %r" % status_code)
+ status_int = int(status_code)
+ assert_(status_int >= 100, "Status code is invalid: %r" % status_int)
+ if len(status) < 4 or status[3] != ' ':
+ warnings.warn(
+ "The status string (%r) should be a three-digit integer "
+ "followed by a single space and a status explanation"
+ % status, WSGIWarning)
+
+def check_headers(headers):
+ assert_(type(headers) is ListType,
+ "Headers (%r) must be of type list: %r"
+ % (headers, type(headers)))
+ header_names = {}
+ for item in headers:
+ assert_(type(item) is TupleType,
+ "Individual headers (%r) must be of type tuple: %r"
+ % (item, type(item)))
+ assert_(len(item) == 2)
+ name, value = item
+ assert_(name.lower() != 'status',
+ "The Status header cannot be used; it conflicts with CGI "
+ "script, and HTTP status is not given through headers "
+ "(value: %r)." % value)
+ header_names[name.lower()] = None
+ assert_('\n' not in name and ':' not in name,
+ "Header names may not contain ':' or '\\n': %r" % name)
+ assert_(header_re.search(name), "Bad header name: %r" % name)
+ assert_(not name.endswith('-') and not name.endswith('_'),
+ "Names may not end in '-' or '_': %r" % name)
+ if bad_header_value_re.search(value):
+ assert_(0, "Bad header value: %r (bad char: %r)"
+ % (value, bad_header_value_re.search(value).group(0)))
+
+def check_content_type(status, headers):
+ code = int(status.split(None, 1)[0])
+ # @@: need one more person to verify this interpretation of RFC 2616
+ # http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html
+ NO_MESSAGE_BODY = (204, 304)
+ for name, value in headers:
+ if name.lower() == 'content-type':
+ if code not in NO_MESSAGE_BODY:
+ return
+ assert_(0, ("Content-Type header found in a %s response, "
+ "which must not return content.") % code)
+ if code not in NO_MESSAGE_BODY:
+ assert_(0, "No Content-Type header found in headers (%s)" % headers)
+
+def check_exc_info(exc_info):
+ assert_(exc_info is None or type(exc_info) is type(()),
+ "exc_info (%r) is not a tuple: %r" % (exc_info, type(exc_info)))
+ # More exc_info checks?
+
+def check_iterator(iterator):
+ # Technically a string is legal, which is why it's a really bad
+ # idea, because it may cause the response to be returned
+ # character-by-character
+ assert_(not isinstance(iterator, str),
+ "You should not return a string as your application iterator, "
+ "instead return a single-item list containing that string.")