synapse-product/synapse/http/server.py
2014-08-31 14:54:58 +01:00

374 lines
13 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2014 matrix.org
#
# 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
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from syutil.jsonutil import (
encode_canonical_json, encode_pretty_printed_json
)
from synapse.api.errors import (
cs_exception, SynapseError, CodeMessageException, Codes, cs_error
)
from synapse.util.stringutils import random_string
from twisted.internet import defer, reactor
from twisted.protocols.basic import FileSender
from twisted.web import server, resource
from twisted.web.server import NOT_DONE_YET
from twisted.web.util import redirectTo
import base64
import collections
import json
import logging
import os
import re
logger = logging.getLogger(__name__)
class HttpServer(object):
""" Interface for registering callbacks on a HTTP server
"""
def register_path(self, method, path_pattern, callback):
""" Register a callback that get's fired if we receive a http request
with the given method for a path that matches the given regex.
If the regex contains groups these get's passed to the calback via
an unpacked tuple.
Args:
method (str): The method to listen to.
path_pattern (str): The regex used to match requests.
callback (function): The function to fire if we receive a matched
request. The first argument will be the request object and
subsequent arguments will be any matched groups from the regex.
This should return a tuple of (code, response).
"""
pass
class JsonResource(HttpServer, resource.Resource):
""" This implements the HttpServer interface and provides JSON support for
Resources.
Register callbacks via register_path()
"""
isLeaf = True
_PathEntry = collections.namedtuple("_PathEntry", ["pattern", "callback"])
def __init__(self):
resource.Resource.__init__(self)
self.path_regexs = {}
def register_path(self, method, path_pattern, callback):
self.path_regexs.setdefault(method, []).append(
self._PathEntry(path_pattern, callback)
)
def start_listening(self, port):
""" Registers the http server with the twisted reactor.
Args:
port (int): The port to listen on.
"""
reactor.listenTCP(port, server.Site(self))
# Gets called by twisted
def render(self, request):
""" This get's called by twisted every time someone sends us a request.
"""
self._async_render(request)
return server.NOT_DONE_YET
@defer.inlineCallbacks
def _async_render(self, request):
""" This get's called by twisted every time someone sends us a request.
This checks if anyone has registered a callback for that method and
path.
"""
try:
# Just say yes to OPTIONS.
if request.method == "OPTIONS":
self._send_response(request, 200, {})
return
# Loop through all the registered callbacks to check if the method
# and path regex match
for path_entry in self.path_regexs.get(request.method, []):
m = path_entry.pattern.match(request.path)
if m:
# We found a match! Trigger callback and then return the
# returned response. We pass both the request and any
# matched groups from the regex to the callback.
code, response = yield path_entry.callback(
request,
*m.groups()
)
self._send_response(request, code, response)
return
# Huh. No one wanted to handle that? Fiiiiiine. Send 400.
self._send_response(
request,
400,
{"error": "Unrecognized request"}
)
except CodeMessageException as e:
if isinstance(e, SynapseError):
logger.error("%s SynapseError: %s - %s", request, e.code,
e.msg)
else:
logger.exception(e)
self._send_response(
request,
e.code,
cs_exception(e)
)
except Exception as e:
logger.exception(e)
self._send_response(
request,
500,
{"error": "Internal server error"}
)
def _send_response(self, request, code, response_json_object):
# could alternatively use request.notifyFinish() and flip a flag when
# the Deferred fires, but since the flag is RIGHT THERE it seems like
# a waste.
if request._disconnected:
logger.warn(
"Not sending response to request %s, already disconnected.",
request)
return
if not self._request_user_agent_is_curl(request):
json_bytes = encode_canonical_json(response_json_object)
else:
json_bytes = encode_pretty_printed_json(response_json_object)
# TODO: Only enable CORS for the requests that need it.
respond_with_json_bytes(request, code, json_bytes, send_cors=True)
@staticmethod
def _request_user_agent_is_curl(request):
user_agents = request.requestHeaders.getRawHeaders(
"User-Agent", default=[]
)
for user_agent in user_agents:
if "curl" in user_agent:
return True
return False
class RootRedirect(resource.Resource):
"""Redirects the root '/' path to another path."""
def __init__(self, path):
resource.Resource.__init__(self)
self.url = path
def render_GET(self, request):
return redirectTo(self.url, request)
def getChild(self, name, request):
if len(name) == 0:
return self # select ourselves as the child to render
return resource.Resource.getChild(self, name, request)
class ContentRepoResource(resource.Resource):
"""Provides file uploading and downloading.
Uploads are POSTed to wherever this Resource is linked to. This resource
returns a "content token" which can be used to GET this content again. The
token is typically a path, but it may not be. Tokens can expire, be one-time
uses, etc.
In this case, the token is a path to the file and contains 3 interesting
sections:
- User ID base64d (for namespacing content to each user)
- random 24 char string
- Content type base64d (so we can return it when clients GET it)
"""
isLeaf = True
def __init__(self, hs, directory, auth):
resource.Resource.__init__(self)
self.hs = hs
self.directory = directory
self.auth = auth
if not os.path.isdir(self.directory):
os.mkdir(self.directory)
logger.info("ContentRepoResource : Created %s directory.",
self.directory)
@defer.inlineCallbacks
def map_request_to_name(self, request):
# auth the user
auth_user = yield self.auth.get_user_by_req(request)
# namespace all file uploads on the user
prefix = base64.urlsafe_b64encode(
auth_user.to_string()
).replace('=', '')
# use a random string for the main portion
main_part = random_string(24)
# suffix with a file extension if we can make one. This is nice to
# provide a hint to clients on the file information. We will also reuse
# this info to spit back the content type to the client.
suffix = ""
if request.requestHeaders.hasHeader("Content-Type"):
content_type = request.requestHeaders.getRawHeaders(
"Content-Type")[0]
suffix = "." + base64.urlsafe_b64encode(content_type)
if (content_type.split("/")[0].lower() in
["image", "video", "audio"]):
file_ext = content_type.split("/")[-1]
# be a little paranoid and only allow a-z
file_ext = re.sub("[^a-z]", "", file_ext)
suffix += "." + file_ext
file_name = prefix + main_part + suffix
file_path = os.path.join(self.directory, file_name)
logger.info("User %s is uploading a file to path %s",
auth_user.to_string(),
file_path)
# keep trying to make a non-clashing file, with a sensible max attempts
attempts = 0
while os.path.exists(file_path):
main_part = random_string(24)
file_name = prefix + main_part + suffix
file_path = os.path.join(self.directory, file_name)
attempts += 1
if attempts > 25: # really? Really?
raise SynapseError(500, "Unable to create file.")
defer.returnValue(file_path)
def render_GET(self, request):
# no auth here on purpose, to allow anyone to view, even across home
# servers.
# TODO: A little crude here, we could do this better.
filename = request.path.split('/')[-1]
# be paranoid
filename = re.sub("[^0-9A-z.-_]", "", filename)
file_path = self.directory + "/" + filename
logger.debug("Searching for %s", file_path)
if os.path.isfile(file_path):
# filename has the content type
base64_contentype = filename.split(".")[1]
content_type = base64.urlsafe_b64decode(base64_contentype)
logger.info("Sending file %s", file_path)
f = open(file_path, 'rb')
request.setHeader('Content-Type', content_type)
d = FileSender().beginFileTransfer(f, request)
# after the file has been sent, clean up and finish the request
def cbFinished(ignored):
f.close()
request.finish()
d.addCallback(cbFinished)
else:
respond_with_json_bytes(
request,
404,
json.dumps(cs_error("Not found", code=Codes.NOT_FOUND)),
send_cors=True)
return server.NOT_DONE_YET
def render_POST(self, request):
self._async_render(request)
return server.NOT_DONE_YET
def render_OPTIONS(self, request):
respond_with_json_bytes(request, 200, {}, send_cors=True)
return server.NOT_DONE_YET
@defer.inlineCallbacks
def _async_render(self, request):
try:
fname = yield self.map_request_to_name(request)
# TODO I have a suspcious feeling this is just going to block
with open(fname, "wb") as f:
f.write(request.content.read())
# FIXME (erikj): These should use constants.
file_name = os.path.basename(fname)
url = "http://%s/_matrix/content/%s" % (
self.hs.domain_with_port, file_name
)
respond_with_json_bytes(request, 200,
json.dumps({"content_token": url}),
send_cors=True)
except CodeMessageException as e:
logger.exception(e)
respond_with_json_bytes(request, e.code,
json.dumps(cs_exception(e)))
except Exception as e:
logger.error("Failed to store file: %s" % e)
respond_with_json_bytes(
request,
500,
json.dumps({"error": "Internal server error"}),
send_cors=True)
def respond_with_json_bytes(request, code, json_bytes, send_cors=False):
"""Sends encoded JSON in response to the given request.
Args:
request (twisted.web.http.Request): The http request to respond to.
code (int): The HTTP response code.
json_bytes (bytes): The json bytes to use as the response body.
send_cors (bool): Whether to send Cross-Origin Resource Sharing headers
http://www.w3.org/TR/cors/
Returns:
twisted.web.server.NOT_DONE_YET"""
request.setResponseCode(code)
request.setHeader(b"Content-Type", b"application/json")
if send_cors:
request.setHeader("Access-Control-Allow-Origin", "*")
request.setHeader("Access-Control-Allow-Methods",
"GET, POST, PUT, DELETE, OPTIONS")
request.setHeader("Access-Control-Allow-Headers",
"Origin, X-Requested-With, Content-Type, Accept")
request.write(json_bytes)
request.finish()
return NOT_DONE_YET