Shift testing for second agordejo gui to the start of the program to work with the new auto-detection

engine/api.py

@@ -196,7 +196,7 @@ def startEngine():
     #Start Event Loop Processing
     eventLoop.fastConnect(nsmServerControl.process)
     eventLoop.fastConnect(jackClient._setPlaybackSeconds)
-    eventLoop.slowConnect(nsmServerControl.processSingleInstance)
+    eventLoop.slowConnect(nsmServerControl.listenToAnotherInstanceAttempt)
 
     #Send initial data
     #The decision if we are already in a session on startup or in "choose a session mode" is handled by callbacks

engine/nsmservercontrol.py

@@ -377,14 +377,19 @@ class NsmServerControl(object):
             self.nsmOSCUrl = o.netloc.split(":")[0], o.port
         else:
             envResult = self._getNsmOSCUrlFromEnvironment()
+            print(2)
             if envResult:
                 #In case there is no actual nsmd running but there still was a NSM_URL env var, e.g. over the network, use this.
                 #There is a corner case that the env is local but the user chose to ignore the GUI way (nsmd 1.6.0) to proivde us directly with a specific URL.
                 self.nsmOSCUrl = envResult
             else:
                 #This is the default case. User just starts the GUI. The other modes are concious decisions to either start with URL as parameter or in an NSM environment.
-                #But now we need to test if the user accidentaly opened a second GUI, which would start a second server.
+                #We need to test if the user accidentaly opened a second GUI, which would start a second server.
                 self._setupAndTestForSingleInstance() #This might quit the whole program and we will never see the next line.
+                #TODO: there is a corner case: 1) manually start nsmd locally   2) start agordejo first time and connect to running nsmd  3) start 2nd agordejo and connect to the same server.
+                #it will not prevent it. But we need it because all other scenarios prevent agordejo multiple times for actual different servers, which is of course wanted.
+                #Better let something uncorrect slip than to prevent legit usecases!
+                #The important check here is to see if Agordejo, with internal nsmd, was started twice or not. Which works. That's all.
                 self.nsmOSCUrl = self._generateFreeNsmOSCUrl()
 
         assert self.nsmOSCUrl
@@ -422,7 +427,7 @@ class NsmServerControl(object):
         self.dataClientNamesHook = dataClientNamesHook
         self.dataClientDescriptionHook = dataClientDescriptionHook
         self.dataClientTimelineMaximumDurationChangedHook = dataClientTimelineMaximumDurationChangedHook
-        self.singleInstanceActivateWindowHook = singleInstanceActivateWindowHook #added to self.processSingleInstance() to listen for a message from another wannabe-instance
+        self.singleInstanceActivateWindowHook = singleInstanceActivateWindowHook #added to self.listenToAnotherInstanceAttempt() to listen for a message from another wannabe-instance
 
         self._receiverActive = True
         logger.info("nsmservercontrol init is complete. Ready for event loop")
@@ -430,22 +435,28 @@ class NsmServerControl(object):
 
     #Internal Methods
     def _setupAndTestForSingleInstance(self):
-        """on program startup trigger this if there is already another instance of us running.
-        This socket is only
+        """
+        On program startup trigger this if there is already another instance of us running.
+        This is before anything NSM was done.
         """
         self.singleInstanceSocket = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
         logger.info("Testing if another non-specific Agordejo is running.")
         try:
-            ## Create an abstract socket, by prefixing it with null.
+            # This is for the first agordejo instance, when no other is running. We set up
+            # a socket and listen throughout the runtime of our instance.
+            #
+            # Create an abstract socket, by prefixing it with null.
             # this relies on a feature only in linux, when current process quits, the
             # socket will be deleted.
             self.singleInstanceSocket.bind('\0' + "agordejo")
             self.singleInstanceSocket.listen(1)
             self.singleInstanceSocket.setblocking(False)
             logger.info("No other non-specific  Agordejo found. Starting GUI")
-            #Continue in self.processSingleInstance()
+            #Continue in self.listenToAnotherInstanceAttempt()
             return True
         except socket.error:
+            # This is for the 2nd agordejo instance that has detected there is already another
+            # instance running.  We will exit here before anything related to NSM has happened.
             logger.error("GUI for this nsmd server already running. Informing the existing application to show itself.")
             self.singleInstanceSocket.connect('\0' + "agordejo")
             self.singleInstanceSocket.send("agordejoactivate".encode());
@@ -454,10 +465,17 @@ class NsmServerControl(object):
             #print ("not executed")
             return False
 
-    def processSingleInstance(self):
-        """Tests our unix socket for an incoming signal.
+    def listenToAnotherInstanceAttempt(self):
+        """
+        This is for the agordejo instance that keeps running. We inform the GUI via hook
+        to show info to the user that a 2nd instance wanted to start.
+
+        Tests our unix socket for an incoming signal.
         if received forward to the engine->gui
-        Can be added to a slower event loop, so it is not in self.process"""
+
+        Must be added to an event loop, so will only start once the program has started.
+        Can be added to a slower event loop, so it is not in self.process
+        """
         if self.singleInstanceSocket:
             try:
                 connection, client_address = self.singleInstanceSocket.accept() #This blocks and waits for a message

engine/start.py

@@ -223,6 +223,34 @@ def checkJackOrExit(prettyName):
         exitWithMessage("JACK Audio Connection Kit is not running. Please start it.")
 
 
+def isAnotherAgordejoInstanceRunning()->bool:
+    import socket
+    tempSocket = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+    try:
+        # This is for the first agordejo instance, when no other is running. We set up
+        # a socket and listen throughout the runtime of our instance.
+        #
+        # Create an abstract socket, by prefixing it with null.
+        # this relies on a feature only in linux, when current process quits, the
+        # socket will be deleted.
+        tempSocket.bind('\0' + "agordejo")
+        tempSocket.listen(1)
+        tempSocket.setblocking(False)
+        return False
+    except socket.error:
+        # This is for the 2nd agordejo instance that has detected there is already another
+        # instance running.  We will exit here before anything related to NSM has happened.
+        tempSocket.connect('\0' + "agordejo")
+        tempSocket.send("agordejoactivate".encode());
+        tempSocket.close()
+        return True
+
+
+def checkAgordejoOrExit():
+    if (not args.url) and isAnotherAgordejoInstanceRunning():
+        exitWithMessage("Another Agordejo instance is already running. Informing it of our start attempt.")
+
+checkAgordejoOrExit()
 checkJackOrExit(METADATA["name"])
 
 try:

qtgui/mainwindow.py

@@ -166,6 +166,7 @@ class MainWindow(QtWidgets.QMainWindow):
 
         #nsmd 1.6.0
         xdgVersionChange(self.qtApp) #may present a blocking dialog, may do nothing.
+        #If another Agordejo is running, and no --nsm-url was set, we will never reach this point.
         checkForRunningNsmd(self.qtApp, PATHS) #may present a blocking dialog, may do nothing. Injects nsm url into PATHS
 
         #Api Callbacks