Launcher script: refactored code significantly (WIP)

- KeyboardInterrupts do not seem to be raised currently
- other functionality should not have changed
- still requires another independent test

LaunchScript/VirtualAcousticsStarterServer.py

@@ -12,6 +12,7 @@ class ErrorCodes(Enum):
   ERROR_MISSING_VA_INI = 5
   ERROR_INVALID_REPRODUCTION_ID = 6
   ERROR_INCOMPLETE_VA_INI = 7
+  ERROR_UNDEFINED_LAUNCHER_STATE = 8
 
 # Class representing the VA-Launcher config (.json) file
 class LauncherConfig:
@@ -51,6 +52,7 @@ class VAComposedIniParser:
 
   def link_renderer_ini(self):
     if not self.sRendererIniPath:
+      print("No renderer ini-file sent by client, using default one.")
       self.sRendererIniPath = "VARenderer.Default.ini"
     
     sMainInifile = self.get_main_inifile()
@@ -103,6 +105,8 @@ class VirtualAcousticsLauncher:
     self.oLauncherServerSocket = None 
     self.oLauncherConnection = None 
     self.sCurrentScriptsDirectory = os.path.dirname( os.path.realpath( sys.argv[0] ) )
+    self.sVAServerID = None
+    self.sVAServerDir = None
 
     self.start()
 
@@ -111,7 +115,7 @@ class VirtualAcousticsLauncher:
     print( "VirtualAcoustics Starter script - press ctrl+c to quit" )
     self.read_config()
     self.open_server_socket()
-    self.run()
+    self.main_loop()
 
 
   #Reads the launcher config and initializes all respective class parameters
@@ -153,17 +157,48 @@ class VirtualAcousticsLauncher:
       sys.exit( ErrorCodes.ERROR_BINDING_SOCKET )
     self.oLauncherServerSocket.settimeout( 1.0 )
 
-  #Actually starts the launcher listening for VAServer start requests
-  def run(self):
+  def _reset_connection(self):
+    if self.oLauncherConnection:
+      self.oLauncherConnection.close()
+      self.oLauncherConnection = None
+    self.sVAServerDir = None
+    self.sVAServerID = None
+
+  def _close_va_and_reset_connection(self):
+    if self.oVAProcess:
+      print( "Closing VA instance" )
+      self.oVAProcess.terminate()
+      time.sleep( 1 )
+      self.oVAProcess.kill()
+      self.oVAProcess = None
+    self._reset_connection()
+
+  def main_loop(self):
     try:
       #TODO-PSC: Receive file and name from client
       self.vaIniParser.sRendererIniPath = None
       self.vaIniParser.prepare_inis()
       while True:
-        print( "Waiting for launcher connection..." )
+        if not self.oLauncherConnection:
+          self.wait_for_connection()
             
-        self.oLauncherConnection = None
+        elif self.sVAServerDir and not self.oVAProcess:
+          self.start_va_server()
+
+        elif self.oVAProcess:
+          self.listen_for_requests()
+
+        else:
+          print("ERROR: Undefined state launcher state leading to infinite loop")
+          sys.exit( ErrorCodes.ERROR_UNDEFINED_LAUNCHER_STATE )
 
+    except KeyboardInterrupt:
+      print( "Caught keyboard interrupt, quitting" )
+
+    self._reset_connection()
+
+  def wait_for_connection(self):
+    print( "Waiting for launcher connection..." )
     while not self.oLauncherConnection:
       try:
         self.oLauncherConnection, sAddress = self.oLauncherServerSocket.accept()
@@ -182,15 +217,7 @@ class VirtualAcousticsLauncher:
       self.oVAProcess.kill()
       self.oVAProcess = None
 
-        sVAServerDir = self.receive_va_server_id()
-        if not sVAServerDir:
-          continue
-
-        self.start_va_server(sVAServerDir)
-    except KeyboardInterrupt:
-      print( "Caught keyboard interrupt, quitting" )
-
-    self.oLauncherServerSocket.close()
+    self.receive_va_server_id()
 
 
   #Checks for a message containing the ID of the VAServer instance to be started and returns the respective VAServer directory
@@ -202,42 +229,42 @@ class VirtualAcousticsLauncher:
       print( "Received launch request for variant: " + self.sVAServerID )
     except socket.error:
       print( "Error while reading variant" )
-      self.oLauncherConnection.close()
-      return None
+      self._reset_connection()
+      return False
     else:
       try:
-        sVAServerDir = self.oConfig.dVirtualAcousticDirectories[self.sVAServerID]
+        self.sVAServerDir = self.oConfig.dVirtualAcousticDirectories[self.sVAServerID]
       except KeyError:
-        sVAServerDir = None
+        self.sVAServerDir = None
 
-      if not sVAServerDir:
+      if not self.sVAServerDir:
         print( 'Requested VA Instance "' + self.sVAServerID + '" not available' )
         self.oLauncherConnection.send( b'f' ) #answer 'requested version not available
-        self.oLauncherConnection.close()
-        return None
+        self._reset_connection()
+        return False
 
-      return sVAServerDir
+      return True
 
   #Starts the VAServer from given directory
-  def start_va_server(self, sVAServerDir):
+  def start_va_server(self):
 
     # Check for VAServer.exe
     sVAExecutableFile = "bin/VAServer.exe"
     try:
       if not os.path.isfile( sVAExecutableFile ):
-        if sVAServerDir and os.path.isfile( sVAServerDir + "/" + sVAExecutableFile ):
-          sVAExecutableFile = sVAServerDir + "/" + sVAExecutableFile
+        if self.sVAServerDir and os.path.isfile( self.sVAServerDir + "/" + sVAExecutableFile ):
+          sVAExecutableFile = self.sVAServerDir + "/" + sVAExecutableFile
         else:
           print( "ERROR: Invalid config for " + self.sVAServerID + " -- file " + sVAExecutableFile + " does not exist" )
           self.oLauncherConnection.send( b'n' ) #answer 'binary file cannot be found or invalid'
           return
-      elif sVAServerDir == None:
-        sVAServerDir = os.path.dirname( sVAExecutableFile ) #TODO-PSC: VAServer should always be started from its main directory, not the "bin" folder
+      elif self.sVAServerDir == None:
+        self.sVAServerDir = os.path.dirname( sVAExecutableFile ) #TODO-PSC: VAServer should always be started from its main directory, not the "bin" folder
     except KeyError:
       sVAExecutableFile = None
       print( "ERROR: config for " + self.sVAServerID + " has no valid \"file\" entry" )
       self.oLauncherConnection.send( b'i' ) #answer 'invalid file entry in the config'
-      self.oLauncherConnection.close()
+      self._reset_connection()
       return
 
     if not sVAExecutableFile:
@@ -252,7 +279,7 @@ class VirtualAcousticsLauncher:
     # start instance
     print( 'executing "' + sCommand + '"' )
           
-    self.oVAProcess = subprocess.Popen( sCommand, cwd = sVAServerDir, creationflags=subprocess.CREATE_NEW_PROCESS_GROUP )
+    self.oVAProcess = subprocess.Popen( sCommand, cwd = self.sVAServerDir, creationflags=subprocess.CREATE_NEW_PROCESS_GROUP )
 
     # wait for requested duration before sending the go signal
     time.sleep( self.oConfig.nDefaultSleep )
@@ -260,22 +287,12 @@ class VirtualAcousticsLauncher:
     if self.oVAProcess.poll() != None:
       print( "VA Process died - sending abort token" )
       self.oLauncherConnection.send( b'a' ) #answer 'VAServer was aborted
-      self.oLauncherConnection.close()
+      self._reset_connection()
       return
     else:        
       print( "sending go token" )
       self.oLauncherConnection.send( b'g' )#answer 'go, VAServer is correctly started'
 
-    self.listen_for_requests()
-
-    #if the above terminates a quit request was received:
-    # kill VA instance
-    print( "Closing VA instance" )
-    self.oVAProcess.terminate()
-    time.sleep( 1 )
-    self.oVAProcess.kill()
-    self.oVAProcess = None
-
   #Listens for requests while the VAServer is running
   def listen_for_requests(self):
     while True:
@@ -289,6 +306,7 @@ class VirtualAcousticsLauncher:
             self.receive_file(sMessage)
           else: #NOT sMessage.startswith("file")      
             print( "Received quit event: "+sMessage )
+            self._close_va_and_reset_connection()
             break
 
       except socket.timeout:
@@ -300,6 +318,7 @@ class VirtualAcousticsLauncher:
       except (KeyboardInterrupt, SystemExit):
         raise #re-raise for higher instance to catch
   
+
   def receive_file(self, sMessage):
     aMessageParts = sMessage.split(":")
     iBytesToReceive = int(aMessageParts[2])
@@ -349,9 +368,8 @@ class VirtualAcousticsLauncher:
         print("File receive failed")
 
 
+
 #create an instance of the class
 oLauncher = VirtualAcousticsLauncher()
 
 
-        
-