ctrl2cgi: properly limit number of requests

Manual acquire()/release() of semaphore does not limit number of
concurrent requests when combined with explicit yield. Fix this by using
semaphore.run() and removing inilineCallbacks decorator.

Change-Id: I47b8b9f5b726ca0905bb7c023d63b325c7f7d85f
Related: SYS#4399

scripts/ctrl2cgi.py

@@ -22,7 +22,7 @@
  */
 """
 
-__version__ = "0.0.5" # bump this on every non-trivial change
+__version__ = "0.0.6" # bump this on every non-trivial change
 
 import argparse, os, logging, logging.handlers
 import hashlib
@@ -60,6 +60,12 @@ def gen_hash(params, skey):
     #print('HASH: \nparams="%r"\ninput="%s" \nres="%s"' %(params, input, res))
     return res
 
+def make_async_req(dst, par, f_write, f_log):
+    d = post(dst, par)
+    d.addCallback(collect, partial(handle_reply, f_write, f_log)) # treq's collect helper is handy to get all reply content at once
+    d.addErrback(lambda e: f_log.critical("HTTP POST error %s while trying to register BSC %s on %s" % (e, par['bsc_id'], dst))) # handle HTTP errors
+    return d
+
 class Trap(CTRL):
     """
     TRAP handler (agnostic to factory's client object)
@@ -93,7 +99,6 @@ class Trap(CTRL):
         self.factory.log.info("Connected to CTRL@%s:%d" % (self.factory.addr_ctrl, self.factory.port_ctrl))
         super(CTRL, self).connectionMade()
 
-    @defer.inlineCallbacks
     def handle_locationstate(self, net, bsc, bts, trx, data):
         """
         Handle location-state TRAP: parse trap content, build CGI Request and use treq's routines to post it while setting up async handlers
@@ -101,13 +106,8 @@ class Trap(CTRL):
         params = make_params(bsc, data)
         self.factory.log.debug('location-state@%s.%s.%s.%s (%s) => %s' % (net, bsc, bts, trx, params['time_stamp'], data))
         params['h'] = gen_hash(params, self.factory.secret_key)
-        d = post(self.factory.location, params)
-        d.addCallback(collect, partial(handle_reply, self.transport.write, self.factory.log)) # treq's collect helper is handy to get all reply content at once
-        d.addErrback(lambda e, bsc: self.factory.log.critical("HTTP POST error %s while trying to register BSC %s on %s" % (e, bsc, self.factory.location)), bsc) # handle HTTP errors
         # Ensure that we run only limited number of requests in parallel:
-        yield self.factory.semaphore.acquire()
-        yield d # we end up here only if semaphore is available which means it's ok to fire the request without exceeding the limit
-        self.factory.semaphore.release()
+        self.factory.semaphore.run(make_async_req, self.factory.location, params, self.transport.write, self.factory.log)
 
     def handle_notificationrejectionv1(self, net, bsc, bts, trx, data):
         """