Source code for falcon.testing.helpers

# Copyright 2013 by Rackspace Hosting, Inc.
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# See the License for the specific language governing permissions and
# limitations under the License.

"""Testing utilities.

This module contains various testing utilities that can be accessed
directly from the `testing` package::

    from falcon import testing

    wsgi_environ = testing.create_environ()


import cgi
import contextlib
import io
import random
import sys

import six

from falcon.util import http_now, uri

# Constants

# NOTE(kgriffs): Alias for backwards-compatibility with Falcon 0.2
httpnow = http_now

# get_encoding_from_headers() is Copyright 2016 Kenneth Reitz, and is
# used here under the terms of the Apache License, Version 2.0.
def get_encoding_from_headers(headers):
    """Returns encoding from given HTTP Header Dict.

        headers(dict): Dictionary from which to extract encoding. Header
            names must either be lowercase or the dict must support
            case-insensitive lookups.

    content_type = headers.get('content-type')

    if not content_type:
        return None

    content_type, params = cgi.parse_header(content_type)

    if 'charset' in params:
        return params['charset'].strip("'\"")

    if 'text' in content_type:
        return 'ISO-8859-1'

    return None

[docs]def rand_string(min, max): """Returns a randomly-generated string, of a random length. Args: min (int): Minimum string length to return, inclusive max (int): Maximum string length to return, inclusive """ int_gen = random.randint string_length = int_gen(min, max) return ''.join([chr(int_gen(ord(' '), ord('~'))) for __ in range(string_length)])
[docs]def create_environ(path='/', query_string='', protocol='HTTP/1.1', scheme='http', host=DEFAULT_HOST, port=None, headers=None, app='', body='', method='GET', wsgierrors=None, file_wrapper=None): """Creates a mock PEP-3333 environ ``dict`` for simulating WSGI requests. Keyword Args: path (str): The path for the request (default '/') query_string (str): The query string to simulate, without a leading '?' (default '') protocol (str): The HTTP protocol to simulate (default 'HTTP/1.1'). If set to 'HTTP/1.0', the Host header will not be added to the environment. scheme (str): URL scheme, either 'http' or 'https' (default 'http') host(str): Hostname for the request (default '') port (str): The TCP port to simulate. Defaults to the standard port used by the given scheme (i.e., 80 for 'http' and 443 for 'https'). headers (dict): Headers as a ``dict`` or an iterable yielding (*key*, *value*) ``tuple``'s app (str): Value for the ``SCRIPT_NAME`` environ variable, described in PEP-333: 'The initial portion of the request URL's "path" that corresponds to the application object, so that the application knows its virtual "location". This may be an empty string, if the application corresponds to the "root" of the server.' (default '') body (str): The body of the request (default ''). Accepts both byte strings and Unicode strings. Unicode strings are encoded as UTF-8 in the request. method (str): The HTTP method to use (default 'GET') wsgierrors (io): The stream to use as *wsgierrors* (default ``sys.stderr``) file_wrapper: Callable that returns an iterable, to be used as the value for *wsgi.file_wrapper* in the environ. """ if query_string and query_string.startswith('?'): raise ValueError("query_string should not start with '?'") body = io.BytesIO(body.encode('utf-8') if isinstance(body, six.text_type) else body) # NOTE(kgriffs): wsgiref, gunicorn, and uWSGI all unescape # the paths before setting PATH_INFO path = uri.decode(path) if six.PY3: # NOTE(kgriffs): The decoded path may contain UTF-8 characters. # But according to the WSGI spec, no strings can contain chars # outside ISO-8859-1. Therefore, to reconcile the URI # encoding standard that allows UTF-8 with the WSGI spec # that does not, WSGI servers tunnel the string via # ISO-8859-1. falcon.testing.create_environ() mimics this # behavior, e.g.: # # tunnelled_path = path.encode('utf-8').decode('iso-8859-1') # # falcon.Request does the following to reverse the process: # # path = tunnelled_path.encode('iso-8859-1').decode('utf-8', 'replace') # path = path.encode('utf-8').decode('iso-8859-1') if six.PY2 and isinstance(path, six.text_type): path = path.encode('utf-8') scheme = scheme.lower() if port is None: port = '80' if scheme == 'http' else '443' else: port = str(port) # NOTE(kgriffs): Judging by the algorithm given in PEP-3333 for # reconstructing the URL, SCRIPT_NAME is expected to contain a # preceding slash character. if app and not app.startswith('/'): app = '/' + app env = { 'SERVER_PROTOCOL': protocol, 'SERVER_SOFTWARE': 'gunicorn/0.17.0', 'SCRIPT_NAME': app, 'REQUEST_METHOD': method, 'PATH_INFO': path, 'QUERY_STRING': query_string, 'HTTP_USER_AGENT': 'curl/7.24.0 (x86_64-apple-darwin12.0)', 'REMOTE_PORT': '65133', 'RAW_URI': '/', 'REMOTE_ADDR': '', 'SERVER_NAME': host, 'SERVER_PORT': port, 'wsgi.version': (1, 0), 'wsgi.url_scheme': scheme, 'wsgi.input': body, 'wsgi.errors': wsgierrors or sys.stderr, 'wsgi.multithread': False, 'wsgi.multiprocess': True, 'wsgi.run_once': False } if file_wrapper is not None: env['wsgi.file_wrapper'] = file_wrapper if protocol != 'HTTP/1.0': host_header = host if scheme == 'https': if port != '443': host_header += ':' + port else: if port != '80': host_header += ':' + port env['HTTP_HOST'] = host_header content_length =, 2) if content_length != 0: env['CONTENT_LENGTH'] = str(content_length) if headers is not None: _add_headers_to_environ(env, headers) return env
[docs]@contextlib.contextmanager def redirected(stdout=sys.stdout, stderr=sys.stderr): """ A context manager to temporarily redirect stdout or stderr e.g.: with redirected(stderr=os.devnull): ... """ old_stdout, old_stderr = sys.stdout, sys.stderr sys.stdout, sys.stderr = stdout, stderr try: yield finally: sys.stderr, sys.stdout = old_stderr, old_stdout
# --------------------------------------------------------------------- # Private # --------------------------------------------------------------------- def _add_headers_to_environ(env, headers): if not isinstance(headers, dict): # Try to convert headers = dict(headers) for name, value in headers.items(): name = name.upper().replace('-', '_') if value is None: value = '' else: value = value.strip() if name == 'CONTENT_TYPE': env[name] = value elif name == 'CONTENT_LENGTH': env[name] = value else: env['HTTP_' + name] = value