We need to run an xml rpc server on each blender session started. Blender communicates with our python 2.7 based pipeline through xml rpc. The xml rpc server will receive python 3.0 commands as strings set to the xml rpc server.

the wall we've been hitting are: -We need the script to be started from the same location on each blender workstation. -When we load the script as an addon, it attemps to spawn several servers on each session when we just need a single one.

Any help would be very welcome on: -How we can load a startup script for blender from a shared location for all users. -How we can make sure one single server is started within each session.

Please bellow the snippet code of what we are trying to get up and running on each blender session:

A Python 3.7 XMLRPC Server program in Blender

bl_info = { "name": "XMLRPC Server", "author": "KristenH", "version": (0, 5, 0, 1), "blender": (2, 79, 0), "category": "System" }

from xmlrpc.server import SimpleXMLRPCServer import threading, time from socketserver import ThreadingMixIn import bpy import sys import socket print() from queue import Queue

Simple server class

class SimpleServer(ThreadingMixIn, SimpleXMLRPCServer): pass # The same statement as Null in C++, Java, C# etc.

The command function

def command(com): com='import bpy\n'+com exec(com) # Trigger command to server return com

The server data

def server_data(): return bpy.app.version_string, bpy.context.blend_data.filepath, socket.gethostname()

def pscan(host='localhost', port=8000): # Setting up a socket sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) proxy = (host, port) try: con = sock.connect(proxy) return True except: pass

class ServerThread(threading.Thread): def init(self, host='localhost', port=8000): self.proxy = (host, port) self.server = SimpleServer(self.proxy) self.port = port self.host = host threading.Thread.init(self) # self.server_thread.setDaemon(True)
self.server.register_introspection_functions() self.server.register_function(command, "command") self.server.register_function(server_data, "server_data") self.version_string = bpy.app.version_string self., bpy.context.blend_data.filepath, socket.gethostname()

A class shows a server panel in Blender

class ServerPanel(bpy.types.Panel): bl_label = "Server Panel" bl_idname = "Object_PT_server" bl_space_type = 'PROPERTIES' bl_region_type = 'WINDOW' bl_category = "Shortcuts"

def draw(self, context):
    layout = self.layout

    row = layout.row()

    server = None
    x = 8000
    attempts = 0
    while(server is None):
        con = pscan(port=x)
        if con is not None:
            print(con, 'found server on', 'localhost:',x)
            row.label(text="Server found on: localhost:" + str(x) + "\n")
            x+=1
        else:
            # time.sleep(5.0)
            server = ServerThread(port=x)
            # Make sure the first port is the start up port.
            # row.label(text="Started the server with:" + str(server.host) + ":" + str(server.port) + "\n")
            print(attempts, "Started the server with:", server.host, ":", server.port)
            server.start()
            # row.label(text="... Press Ctrl+C to exit\n")
            #print("... Press Ctrl+C to exit")
            attempts+=1
            break

Blender code below

def register(): bpy.utils.register_class(ServerPanel) #bpy.utils.register_class(SimpleServer) #bpy.utils.register_class(ServerThread)

def unregister(): bpy.utils.unregister_class(ServerPanel) #bpy.utils.unregister_class(SimpleServer) #bpy.utils.unregister_class(ServerThread)

if name == "main": register()

Many Thanks,

-H.