--- a/rdfdb/patch.py	Sun May 26 00:36:32 2019 +0000
+++ b/rdfdb/patch.py	Sun May 26 19:29:59 2019 +0000
@@ -1,5 +1,6 @@
 import json, unittest
 from rdflib import ConjunctiveGraph, Graph, URIRef, URIRef as U, Literal, Namespace
+from typing import Optional
 XSD = Namespace("http://www.w3.org/2001/XMLSchema#")
 
 
@@ -27,7 +28,8 @@
     
     the json representation includes the {"patch":...} wrapper
     """
-    def __init__(self, jsonRepr=None, addQuads=None, delQuads=None,
+    def __init__(self, jsonRepr: Optional[str]=None,
+                 addQuads=None, delQuads=None,
                  addGraph=None, delGraph=None):
         """
         addQuads/delQuads can be lists or sets, but if we make them internally,
@@ -110,12 +112,12 @@
         return self._delGraph
 
     @property
-    def jsonRepr(self) -> bytes:
+    def jsonRepr(self) -> str:
         if self._jsonRepr is None:
             self._jsonRepr = self.makeJsonRepr()
         return self._jsonRepr
 
-    def makeJsonRepr(self, extraAttrs={}) -> bytes:
+    def makeJsonRepr(self, extraAttrs={}) -> str:
         d = {"patch" : {
             'adds' : serializeQuad(self.addGraph),
             'deletes' : serializeQuad(self.delGraph),
@@ -126,7 +128,7 @@
         if '[<' in d['patch']['adds']:
             raise ValueError("[< found in %s" % d['patch']['adds'])
         d.update(extraAttrs)
-        return json.dumps(d).encode('utf8')
+        return json.dumps(d)
 
     def simplify(self):
         adds = set(self.addQuads)

--- a/rdfdb/service.py	Sun May 26 00:36:32 2019 +0000
+++ b/rdfdb/service.py	Sun May 26 19:29:59 2019 +0000
@@ -53,7 +53,7 @@
         return sendPatch(self.updateUri, p)
         
 class WsClient(object):
-    def __init__(self, connectionId, sendMessage):
+    def __init__(self, connectionId: bytes, sendMessage):
         self.updateUri = connectionId
         self.sendMessage = sendMessage
 
@@ -325,7 +325,7 @@
     wsClient: Optional[WsClient] = None
     def connectionMade(self, *args, **kwargs):
         global _wsClientSerial
-        connectionId = 'connection-%s' % _wsClientSerial
+        connectionId = ('connection-%s' % _wsClientSerial).encode('utf8')
         _wsClientSerial += 1
 
         self.wsClient = WsClient(connectionId, self.sendMessage)
@@ -337,12 +337,12 @@
         self.settings.db.clientErrored(
             Failure(WebsocketDisconnect(reason)), self.wsClient)
 
-    def messageReceived(self, message):
-        if message == 'PING':
+    def messageReceived(self, message: bytes):
+        if message == b'PING':
             self.sendMessage('PONG')
             return
         log.info("got message from %r: %s", self.wsClient, message)
-        p = Patch(jsonRepr=message)
+        p = Patch(jsonRepr=message.decode('utf8'))
         p.senderUpdateUri = self.wsClient.updateUri
         self.settings.db.patch(p)