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| author | Marc Abramowitz <marc@marc-abramowitz.com> | 2016-03-07 18:52:36 -0800 |
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| committer | Marc Abramowitz <marc@marc-abramowitz.com> | 2016-03-07 18:52:36 -0800 |
| commit | cc83e06efff71b81ca5a3ac6df65775971181295 (patch) | |
| tree | d52fa3f1a93730f263c2c5ac8266de8e5fb12abf /paste/auth/form.py | |
| download | paste-git-tox_coverage.tar.gz | |
tox.ini: Measure test coveragetox_coverage
Diffstat (limited to 'paste/auth/form.py')
| -rw-r--r-- | paste/auth/form.py | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/paste/auth/form.py b/paste/auth/form.py new file mode 100644 index 0000000..9be82a2 --- /dev/null +++ b/paste/auth/form.py @@ -0,0 +1,149 @@ +# (c) 2005 Clark C. Evans +# This module is part of the Python Paste Project and is released under +# the MIT License: http://www.opensource.org/licenses/mit-license.php +# This code was written with funding by http://prometheusresearch.com +""" +Authentication via HTML Form + +This is a very simple HTML form login screen that asks for the username +and password. This middleware component requires that an authorization +function taking the name and passsword and that it be placed in your +application stack. This class does not include any session management +code or way to save the user's authorization; however, it is easy enough +to put ``paste.auth.cookie`` in your application stack. + +>>> from paste.wsgilib import dump_environ +>>> from paste.httpserver import serve +>>> from paste.auth.cookie import AuthCookieHandler +>>> from paste.auth.form import AuthFormHandler +>>> def authfunc(environ, username, password): +... return username == password +>>> serve(AuthCookieHandler( +... AuthFormHandler(dump_environ, authfunc))) +serving on... + +""" +from paste.request import construct_url, parse_formvars + +TEMPLATE = """\ +<html> + <head><title>Please Login!</title></head> + <body> + <h1>Please Login</h1> + <form action="%s" method="post"> + <dl> + <dt>Username:</dt> + <dd><input type="text" name="username"></dd> + <dt>Password:</dt> + <dd><input type="password" name="password"></dd> + </dl> + <input type="submit" name="authform" /> + <hr /> + </form> + </body> +</html> +""" + +class AuthFormHandler(object): + """ + HTML-based login middleware + + This causes a HTML form to be returned if ``REMOTE_USER`` is + not found in the ``environ``. If the form is returned, the + ``username`` and ``password`` combination are given to a + user-supplied authentication function, ``authfunc``. If this + is successful, then application processing continues. + + Parameters: + + ``application`` + + The application object is called only upon successful + authentication, and can assume ``environ['REMOTE_USER']`` + is set. If the ``REMOTE_USER`` is already set, this + middleware is simply pass-through. + + ``authfunc`` + + This is a mandatory user-defined function which takes a + ``environ``, ``username`` and ``password`` for its first + three arguments. It should return ``True`` if the user is + authenticated. + + ``template`` + + This is an optional (a default is provided) HTML + fragment that takes exactly one ``%s`` substution + argument; which *must* be used for the form's ``action`` + to ensure that this middleware component does not alter + the current path. The HTML form must use ``POST`` and + have two input names: ``username`` and ``password``. + + Since the authentication form is submitted (via ``POST``) + neither the ``PATH_INFO`` nor the ``QUERY_STRING`` are accessed, + and hence the current path remains _unaltered_ through the + entire authentication process. If authentication succeeds, the + ``REQUEST_METHOD`` is converted from a ``POST`` to a ``GET``, + so that a redirect is unnecessary (unlike most form auth + implementations) + """ + + def __init__(self, application, authfunc, template=None): + self.application = application + self.authfunc = authfunc + self.template = template or TEMPLATE + + def __call__(self, environ, start_response): + username = environ.get('REMOTE_USER','') + if username: + return self.application(environ, start_response) + + if 'POST' == environ['REQUEST_METHOD']: + formvars = parse_formvars(environ, include_get_vars=False) + username = formvars.get('username') + password = formvars.get('password') + if username and password: + if self.authfunc(environ, username, password): + environ['AUTH_TYPE'] = 'form' + environ['REMOTE_USER'] = username + environ['REQUEST_METHOD'] = 'GET' + environ['CONTENT_LENGTH'] = '' + environ['CONTENT_TYPE'] = '' + del environ['paste.parsed_formvars'] + return self.application(environ, start_response) + + content = self.template % construct_url(environ) + start_response("200 OK", [('Content-Type', 'text/html'), + ('Content-Length', str(len(content)))]) + return [content] + +middleware = AuthFormHandler + +__all__ = ['AuthFormHandler'] + +def make_form(app, global_conf, realm, authfunc, **kw): + """ + Grant access via form authentication + + Config looks like this:: + + [filter:grant] + use = egg:Paste#auth_form + realm=myrealm + authfunc=somepackage.somemodule:somefunction + + """ + from paste.util.import_string import eval_import + import types + authfunc = eval_import(authfunc) + assert isinstance(authfunc, types.FunctionType), "authfunc must resolve to a function" + template = kw.get('template') + if template is not None: + template = eval_import(template) + assert isinstance(template, str), "template must resolve to a string" + + return AuthFormHandler(app, authfunc, template) + +if "__main__" == __name__: + import doctest + doctest.testmod(optionflags=doctest.ELLIPSIS) |