zulip/zerver/lib/rest.py

94 lines
3.8 KiB
Python

from __future__ import absolute_import
from django.views.decorators.csrf import csrf_exempt, csrf_protect
from zerver.decorator import authenticated_json_view, authenticated_rest_api_view, \
process_as_post, JsonableError
from zerver.lib.response import json_method_not_allowed, json_unauthorized, json_unhandled_exception
from django.http import HttpResponse, HttpResponseRedirect
from django.conf import settings
import logging
METHODS = ('GET', 'HEAD', 'POST', 'PUT', 'DELETE', 'PATCH')
@csrf_exempt
def rest_dispatch(request, globals_list, **kwargs):
"""Dispatch to a REST API endpoint.
This calls the function named in kwargs[request.method], if that request
method is supported, and after wrapping that function to:
* protect against CSRF (if the user is already authenticated through
a Django session)
* authenticate via an API key (otherwise)
* coerce PUT/PATCH/DELETE into having POST-like semantics for
retrieving variables
Any keyword args that are *not* HTTP methods are passed through to the
target function.
Note that we search views.py globals for the function to call, so never
make a urls.py pattern put user input into a variable called GET, POST,
etc.
"""
supported_methods = {}
# duplicate kwargs so we can mutate the original as we go
for arg in list(kwargs):
if arg in METHODS:
supported_methods[arg] = kwargs[arg]
del kwargs[arg]
if request.method == 'OPTIONS':
response = HttpResponse(status=204) # No content
response['Allow'] = ', '.join(supported_methods.keys())
response['Content-Length'] = "0"
return response
# Override requested method if magic method=??? parameter exists
method_to_use = request.method
if request.POST and 'method' in request.POST:
method_to_use = request.POST['method']
if method_to_use in supported_methods.keys():
target_function = globals_list[supported_methods[method_to_use]]
# Set request._query for update_activity_user(), which is called
# by some of the later wrappers.
request._query = target_function.__name__
# We want to support authentication by both cookies (web client)
# and API keys (API clients). In the former case, we want to
# do a check to ensure that CSRF etc is honored, but in the latter
# we can skip all of that.
#
# Security implications of this portion of the code are minimal,
# as we should worst-case fail closed if we miscategorise a request.
if not request.path.startswith("/api") and request.user.is_authenticated():
# Authenticated via sessions framework, only CSRF check needed
target_function = csrf_protect(authenticated_json_view(target_function))
elif request.META.get('HTTP_AUTHORIZATION', None):
# Wrap function with decorator to authenticate the user before
# proceeding
target_function = authenticated_rest_api_view(target_function)
else:
if 'text/html' in request.META.get('HTTP_ACCEPT', ''):
# If this looks like a request from a top-level page in a
# browser, send the user to the login page
return HttpResponseRedirect('%s/?next=%s' % (settings.HOME_NOT_LOGGED_IN, request.path))
else:
return json_unauthorized("Not logged in: API authentication or user session required")
if request.method not in ["GET", "POST"]:
# process_as_post needs to be the outer decorator, because
# otherwise we might access and thus cache a value for
# request.REQUEST.
target_function = process_as_post(target_function)
return target_function(request, **kwargs)
return json_method_not_allowed(supported_methods.keys())