# Copyright (C) 2012 W. Trevor King <wking@tremily.us>
#
# This file is part of Bugs Everywhere.
#
# Bugs Everywhere is free software: you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the Free
# Software Foundation, either version 2 of the License, or (at your option) any
# later version.
#
# Bugs Everywhere is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
# FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
# more details.
#
# You should have received a copy of the GNU General Public License along with
# Bugs Everywhere. If not, see <http://www.gnu.org/licenses/>.
# For urllib2 information, see
# urllib2, from urllib2 - The Missing Manual
# http://www.voidspace.org.uk/python/articles/urllib2.shtml
#
# A dictionary of response codes is available in
# httplib.responses
# but it is slow to load.
import urllib.request, urllib.parse, urllib.error
import urllib.request, urllib.error, urllib.parse
from libbe import TESTING
if TESTING:
import unittest
HTTP_OK = 200
HTTP_FOUND = 302
HTTP_TEMP_REDIRECT = 307
HTTP_USER_ERROR = 418
"""Status returned to indicate exceptions on the server side.
A BE-specific extension to the HTTP/1.1 protocol (See `RFC 2616`_).
.. _RFC 2616: http://www.w3.org/Protocols/rfc2616/rfc2616-sec6.html#sec6.1.1
"""
HTTP_VALID = [HTTP_OK, HTTP_FOUND, HTTP_TEMP_REDIRECT, HTTP_USER_ERROR]
USER_AGENT = 'BE-agent'
class HTTPError (Exception):
def __init__(self, error=None, url=None, msg=None):
Exception.__init__(self, msg)
self.url = url
self.error = error
self.msg = msg
def __str__(self):
if self.msg is None:
if self.error is None:
return 'Unknown HTTP error: {}'.format(self.url)
return str(self.error)
return self.msg
def get_post_url(url, get=True, data=None, data_dict=None, headers=[],
agent=None):
"""Execute a GET or POST transaction.
Parameters
----------
url : str
The base URL (query portion added internally, if necessary).
get : bool
Use GET if True, otherwise use POST.
data : str
Raw data to send by POST (requires POST).
data_dict : dict
Data to send, either by URL query (if GET) or by POST (if POST).
Cannot be given in combination with `data`.
headers : list
Extra HTTP headers to add to the request.
agent : str
User agent string overriding the BE default.
"""
if agent is None:
agent = USER_AGENT
if data is None:
if data_dict is None:
data_dict = {}
if get is True:
if data_dict != {}:
# encode get parameters in the url
param_string = urllib.parse.urlencode(data_dict)
url = '{}?{}'.format(url, param_string)
else:
data = urllib.parse.urlencode(data_dict)
else:
assert get is False, (data, get)
assert data_dict is None, (data, data_dict)
headers = dict(headers)
headers['User-Agent'] = agent
req = urllib.request.Request(url, data=data, headers=headers)
try:
response = urllib.request.urlopen(req)
except urllib.error.HTTPError as e:
if e.code == HTTP_USER_ERROR:
lines = ['The server reported a user error (HTTPError)']
else:
lines = ['The server reported an error (HTTPError)']
lines.append('URL: {}'.format(url))
if hasattr(e, 'reason'):
lines.append('Reason: {}'.format(e.reason))
lines.append('Error code: {}'.format(e.code))
msg = '\n'.join(lines)
raise HTTPError(error=e, url=url, msg=msg)
except urllib.error.URLError as e:
msg = ('We failed to connect to the server (URLError).\nURL: {}\n'
'Reason: {}').format(url, e.reason)
raise HTTPError(error=e, url=url, msg=msg)
page = response.read()
final_url = response.geturl()
info = response.info()
response.close()
return (page, final_url, info)
if TESTING:
class GetPostUrlTestCase (unittest.TestCase):
"""Test cases for get_post_url()"""
def test_get(self):
url = 'http://bugseverywhere.org/'
page,final_url,info = get_post_url(url=url)
self.assertTrue(final_url == url,
'Redirect?\n Expected: "{}"\n Got: "{}"'.format(
url, final_url))
def test_get_redirect(self):
url = 'http://physics.drexel.edu/~wking/code/be/redirect'
expected = 'http://physics.drexel.edu/~wking/'
page,final_url,info = get_post_url(url=url)
self.assertTrue(final_url == expected,
'Redirect?\n Expected: "{}"\n Got: "{}"'.format(
expected, final_url))
