added RPCServer.help(); switched from SimpleXMLRPCServer to DocXMLRPCServer; some docstrings

grum/mainwin.py

@@ -47,7 +47,7 @@ class MainWindow(QMainWindow):
 
         self.setCentralWidget(splitter)
 
-        rst = RPCServerThread(host, port)
+        rst = RPCServerThread(host, port, doc_title_suffix="grum")
         rst.start()
         rst.server.register_function(self.new_plot)
         rst.server.register_function(self.append_data)

grum/rpc/rpcserver.py

@@ -1,16 +1,39 @@
 import xmlrpc.server as xrs
+from inspect import getdoc, signature
 
 
-class RPCServer(xrs.SimpleXMLRPCServer):
+class RPCServer(xrs.DocXMLRPCServer):
 
-    def __init__(self, host, port, *args, **kwargs):
+    def __init__(self, host, port, doc_title_suffix="", *args, **kwargs):
         addr = (host, port)
         kwargs.setdefault("allow_none", True)
         super().__init__(addr, *args, **kwargs)
+
+        if doc_title_suffix:
+            self.server_name  = doc_title_suffix + " " + self.server_name
+            self.server_title = doc_title_suffix + " " + self.server_title
+
         self.register_function(self.ping)
+        self.register_function(self.help)
+
 
     def ping(self):
+        """
+        Returns "pong". May be used for testing the connection.
+        """
         return "pong"
 
 
+    def help(self):
+        """
+        Returns a dict mapping names of exposed functions to dicts holding their signature and docstring.
+        """
+        res = {}
+        for name, func in self.funcs.items():
+            doc = getdoc(func)
+            sig = str(signature(func))
+            res[name] = dict(signature=sig, docstring=doc)
+        return res
+
+