1 import sys, os, time, md5, random
2 from mod_python import apache, util
3 import osrf.system, osrf.cache, osrf.json, osrf.conf, osrf.net, osrf.log
4 from osrf.const import OSRF_MESSAGE_TYPE_DISCONNECT, OSRF_MESSAGE_TYPE_CONNECT, \
5 OSRF_STATUS_CONTINUE, OSRF_STATUS_TIMEOUT, OSRF_MESSAGE_TYPE_STATUS
9 Proof of concept OpenSRF-HTTP multipart streaming gateway.
11 Example Apache mod_python config:
13 <Location /osrf-http-translator>
15 PythonPath "['/path/to/osrf-python'] + sys.path"
16 PythonHandler osrf.http_translator
17 PythonOption OSRF_CONFIG /path/to/opensrf_core.xml
18 PythonOption OSRF_CONFIG_CONTEXT config.gateway
19 PythonOption OSRF_CACHE_SERVERS 127.0.0.1:11211
25 OSRF_HTTP_HEADER_TO = 'X-OpenSRF-to'
26 OSRF_HTTP_HEADER_XID = 'X-OpenSRF-xid'
27 OSRF_HTTP_HEADER_FROM = 'X-OpenSRF-from'
28 OSRF_HTTP_HEADER_THREAD = 'X-OpenSRF-thread'
29 OSRF_HTTP_HEADER_TIMEOUT = 'X-OpenSRF-timeout'
30 OSRF_HTTP_HEADER_SERVICE = 'X-OpenSRF-service'
31 OSRF_HTTP_HEADER_MULTIPART = 'X-OpenSRF-multipart'
32 MULTIPART_CONTENT_TYPE = 'multipart/x-mixed-replace;boundary="%s"'
33 JSON_CONTENT_TYPE = 'text/plain'
39 # If DEBUG_WRITE = True, all data sent to the client is also written
40 # to stderr (apache error log)
45 sys.stderr.write("%s\n\n" % str(msg))
51 ''' At time of writing, mod_python doesn't support a child_init handler,
52 so this function is called once per process to initialize
53 the opensrf connection '''
55 global INIT_COMPLETE, ROUTER_NAME, OSRF_DOMAIN
59 # Apache complains with: UnboundLocalError: local variable 'osrf' referenced before assignment
60 # if the following import line is removed, even though its also at the top of the file...
63 ops = req.get_options()
64 conf = ops['OSRF_CONFIG']
65 ctxt = ops.get('OSRF_CONFIG_CONTEXT') or 'opensrf'
66 osrf.system.System.net_connect(config_file=conf, config_context=ctxt)
68 ROUTER_NAME = osrf.conf.get('router_name')
69 OSRF_DOMAIN = osrf.conf.get('domain')
72 servers = ops.get('OSRF_CACHE_SERVERS')
74 servers = servers.split(',')
76 # no cache servers configured, see if we can talk to the settings server
78 servers = osrf.set.get('cache.global.servers.server')
79 if not isinstance(servers, list):
82 osrf.cache.CacheClient.connect(servers)
86 ''' Create the translator and tell it to process the request. '''
88 translator = HTTPTranslator(req)
89 status = translator.process()
90 osrf.log.log_debug("translator call resulted in status %d" % int(status))
91 if translator.local_xid:
95 class HTTPTranslator(object):
96 def __init__(self, apreq):
102 for k,v in apreq.headers_in.iteritems():
103 osrf.log.log_internal('HEADER: %s = %s' % (k, v))
106 post = util.parse_qsl(apreq.read(int(apreq.headers_in['Content-length'])))
107 osrf.log.log_debug('post = ' + str(post))
108 self.body = [d for d in post if d[0] == 'osrf-msg'][0][1]
109 osrf.log.log_debug(self.body)
111 osrf.log.log_warn("error parsing osrf message: %s" % unicode(e))
116 self.complete = False
117 self.handle = osrf.net.get_network_handle()
118 self.handle.set_receive_callback(None)
120 self.recipient = apreq.headers_in.get(OSRF_HTTP_HEADER_TO)
121 self.service = apreq.headers_in.get(OSRF_HTTP_HEADER_SERVICE)
122 self.thread = apreq.headers_in.get(OSRF_HTTP_HEADER_THREAD) or \
123 "%s%s" % (os.getpid(), time.time())
124 self.timeout = apreq.headers_in.get(OSRF_HTTP_HEADER_TIMEOUT) or 1200
125 self.multipart = str(
126 apreq.headers_in.get(OSRF_HTTP_HEADER_MULTIPART)).lower() == 'true'
127 self.connect_only = False
128 self.disconnect_only = False
130 # generate a random multipart delimiter
132 mpart.update("%f%d%d" % (time.time(), os.getpid(), \
133 random.randint(100, 10000000)))
134 self.delim = mpart.hexdigest()
135 self.remote_host = self.apreq.get_remote_host(apache.REMOTE_NOLOOKUP)
136 self.cache = osrf.cache.CacheClient()
138 if OSRF_HTTP_HEADER_XID in apreq.headers_in:
139 osrf.log.log_debug('read XID from client %s' % apreq.headers_in.get(OSRF_HTTP_HEADER_XID))
140 osrf.log.set_xid(apreq.headers_in.get(OSRF_HTTP_HEADER_XID))
141 self.local_xid = False
144 osrf.log.log_debug('created new XID %s' % osrf.log.get_xid())
145 self.local_xid = True
150 if self.apreq.header_only:
153 return apache.HTTP_BAD_REQUEST
154 if not self.set_to_addr():
155 return apache.HTTP_BAD_REQUEST
156 if not self.parse_request():
157 return apache.HTTP_BAD_REQUEST
159 while self.handle.recv(0):
160 pass # drop stale messages
163 net_msg = osrf.net.NetworkMessage(
164 recipient=self.recipient, thread=self.thread, body=self.body)
165 self.handle.send(net_msg)
167 if self.disconnect_only:
168 osrf.log.log_debug("exiting early on DISCONNECT")
172 while not self.complete:
176 net_msg = self.handle.recv(self.timeout)
177 except osrf.net.XMPPNoRecipient:
178 return apache.HTTP_NOT_FOUND
181 return apache.GATEWAY_TIME_OUT
183 if not self.check_status(net_msg):
187 self.init_headers(net_msg)
191 self.respond_chunk(net_msg)
192 if self.connect_only:
195 self.messages.append(net_msg.body)
197 # condense the sets of arrays into a single array of messages
198 if self.complete or self.connect_only:
199 json = self.messages.pop(0)
200 while len(self.messages) > 0:
201 msg = self.messages.pop(0)
202 json = "%s,%s" % (json[0:len(json)-1], msg[1:])
204 self.write("%s" % json)
209 def parse_request(self):
211 If this is solely a DISCONNECT message, we set self.disconnect_only
213 @return True if the body parses correctly, False otherwise
215 osrf_msgs = osrf.json.to_object(self.body)
219 if len(osrf_msgs) == 1:
220 if osrf_msgs[0].type() == OSRF_MESSAGE_TYPE_CONNECT:
221 self.connect_only = True
222 elif osrf_msgs[0].type() == OSRF_MESSAGE_TYPE_DISCONNECT:
223 self.disconnect_only = True
228 def set_to_addr(self):
229 ''' Determines the TO address. Returns false if
230 the address is missing or ambiguous.
231 Also returns false if an explicit TO is specified and the
232 thread/IP/TO combination is not found in the session cache
236 osrf.log.log_warn("specifying both SERVICE and TO is not allowed")
238 self.recipient = "%s@%s/%s" % \
239 (ROUTER_NAME, OSRF_DOMAIN, self.service)
240 osrf.log.log_debug("set service to %s" % self.recipient)
244 # If the client specifies a specific TO address, verify it's
245 # the same address that was cached with the previous request.
246 obj = self.cache.get(self.thread)
247 if obj and obj['ip'] == self.remote_host and \
248 obj['jid'] == self.recipient:
250 osrf.log.log_warn("client [%s] attempted to send directly "
251 "[%s] without a session" % (self.remote_host, self.recipient))
255 def init_headers(self, net_msg):
256 osrf.log.log_debug("initializing request headers")
257 self.apreq.headers_out[OSRF_HTTP_HEADER_FROM] = net_msg.sender
258 self.apreq.headers_out[OSRF_HTTP_HEADER_THREAD] = self.thread
260 self.apreq.content_type = MULTIPART_CONTENT_TYPE % self.delim
261 self.write("--%s\n" % self.delim)
263 self.apreq.content_type = JSON_CONTENT_TYPE
264 self.cache.put(self.thread, \
265 {'ip':self.remote_host, 'jid': net_msg.sender}, CACHE_TIME)
267 osrf.log.log_debug("caching session [%s] for host [%s] and server "
268 " drone [%s]" % (self.thread, self.remote_host, net_msg.sender))
272 def check_status(self, net_msg):
273 ''' Checks the status of the server response.
274 If we received a timeout message, we drop it.
275 if it's any other non-continue status, we mark this session as
276 complete and carry on.
277 @return False if there is no data to return to the caller
278 (dropped message, eg. timeout), True otherwise '''
280 osrf.log.log_debug('checking status...')
281 osrf_msgs = osrf.json.to_object(net_msg.body)
282 last_msg = osrf_msgs.pop()
284 if last_msg.type() == OSRF_MESSAGE_TYPE_STATUS:
285 code = int(last_msg.payload().statusCode())
286 osrf.log.log_debug("got a status message with code %d" % code)
288 if code == OSRF_STATUS_TIMEOUT:
289 osrf.log.log_debug("removing cached session [%s] and "
290 "dropping TIMEOUT message" % net_msg.thread)
291 self.cache.delete(net_msg.thread)
294 if code != OSRF_STATUS_CONTINUE:
300 def respond_chunk(self, resp):
301 ''' Writes a single multipart-delimited chunk of data '''
303 self.write("Content-type: %s\n\n" % JSON_CONTENT_TYPE)
304 self.write("%s\n\n" % resp.body)
306 self.write("--%s--\n" % self.delim)
308 self.write("--%s\n" % self.delim)
311 def write(self, msg):
312 ''' Writes data to the client stream. '''
315 sys.stderr.write(msg)
317 self.apreq.write(msg)