Added keepalive packets to accelerate mode

Commands will now be started up in a separate task from the main
handler thread, so that it can be monitored for completeness while
sending a keepalive packet back to the controller to avoid a socket
receive timeout.

utilities/accelerate

@@ -58,24 +58,25 @@ EXAMPLES = '''
       - command: /usr/bin/anything
 '''
 
-import os
-import os.path
-import tempfile
-import sys
-import shutil
-import socket
-import struct
-import time
 import base64
 import getpass
+import os
+import os.path
+import shutil
+import signal
+import socket
+import struct
+import sys
 import syslog
-import signal
+import tempfile
 import time
-import signal
 import traceback
 
 import SocketServer
 
+from datetime import datetime
+from threading import Thread
+
 syslog.openlog('ansible-%s' % os.path.basename(__file__))
 PIDFILE = os.path.expanduser("~/.accelerate.pid")
 
@@ -160,6 +161,19 @@ def daemonize_self(module, password, port, minutes):
     os.dup2(dev_null.fileno(), sys.stderr.fileno())
     log("daemonizing successful")
 
+class ThreadWithReturnValue(Thread):
+    def __init__(self, group=None, target=None, name=None, args=(), kwargs={}, Verbose=None):
+        Thread.__init__(self, group, target, name, args, kwargs, Verbose)
+        self._return = None
+
+    def run(self):
+        if self._Thread__target is not None:
+            self._return = self._Thread__target(*self._Thread__args,
+                                                **self._Thread__kwargs)
+    def join(self,timeout=None):
+        Thread.join(self, timeout=timeout)
+        return self._return
+
 class ThreadedTCPServer(SocketServer.ThreadingTCPServer):
     def __init__(self, server_address, RequestHandlerClass, module, password):
         self.module = module
@@ -193,47 +207,70 @@ class ThreadedTCPRequestHandler(SocketServer.BaseRequestHandler):
                 vvv("received nothing, bailing out")
                 return None
             data += d
+            vvvv("data received so far (expecting %d): %d" % (data_len,len(data)))
         vvvv("received all of the data, returning")
         return data
 
     def handle(self):
-        while True:
+        try:
-            vvvv("waiting for data")
+            while True:
-            data = self.recv_data()
+                vvvv("waiting for data")
-            if not data:
+                data = self.recv_data()
-                vvvv("received nothing back from recv_data(), breaking out")
+                if not data:
-                break
+                    vvvv("received nothing back from recv_data(), breaking out")
-            try:
+                    break
-                vvvv("got data, decrypting")
+                try:
-                data = self.server.key.Decrypt(data)
+                    vvvv("got data, decrypting")
-                vvvv("decryption done")
+                    data = self.server.key.Decrypt(data)
-            except:
+                    vvvv("decryption done")
-                vv("bad decrypt, skipping...")
+                except:
-                data2 = json.dumps(dict(rc=1))
+                    vv("bad decrypt, skipping...")
+                    data2 = json.dumps(dict(rc=1))
+                    data2 = self.server.key.Encrypt(data2)
+                    send_data(client, data2)
+                    return
+
+                vvvv("loading json from the data")
+                data = json.loads(data)
+
+                mode = data['mode']
+                response = {}
+                last_pong = datetime.now()
+                if mode == 'command':
+                    vvvv("received a command request, running it")
+                    twrv = ThreadWithReturnValue(target=self.command, args=(data,))
+                    twrv.start()
+                    response = None
+                    while twrv.is_alive():
+                        if (datetime.now() - last_pong).seconds >= 15:
+                            last_pong = datetime.now()
+                            vvvv("command still running, sending keepalive packet")
+                            data2 = json.dumps(dict(pong=True))
+                            data2 = self.server.key.Encrypt(data2)
+                            self.send_data(data2)
+                        time.sleep(0.1)
+                    response = twrv._return
+                    vvvv("thread is done, response from join was %s" % response)
+                elif mode == 'put':
+                    vvvv("received a put request, putting it")
+                    response = self.put(data)
+                elif mode == 'fetch':
+                    vvvv("received a fetch request, getting it")
+                    response = self.fetch(data)
+
+                vvvv("response result is %s" % str(response))
+                data2 = json.dumps(response)
                 data2 = self.server.key.Encrypt(data2)
-                send_data(client, data2)
+                vvvv("sending the response back to the controller")
-                return
+                self.send_data(data2)
-
+                vvvv("done sending the response")
-            vvvv("loading json from the data")
+        except:
-            data = json.loads(data)
+            tb = traceback.format_exc()
-
+            log("encountered an unhandled exception in the handle() function")
-            mode = data['mode']
+            log("error was:\n%s" % tb)
-            response = {}
+            data2 = json.dumps(dict(rc=1, failed=True, msg="unhandled error in the handle() function"))
-            if mode == 'command':
-                vvvv("received a command request, running it")
-                response = self.command(data)
-            elif mode == 'put':
-                vvvv("received a put request, putting it")
-                response = self.put(data)
-            elif mode == 'fetch':
-                vvvv("received a fetch request, getting it")
-                response = self.fetch(data)
-
-            data2 = json.dumps(response)
             data2 = self.server.key.Encrypt(data2)
-            vvvv("sending the response back to the controller")
             self.send_data(data2)
-            vvvv("done sending the response")
 
     def command(self, data):
         if 'cmd' not in data: