Various fixups to the RPC api.

* change how restorer works
* fix join_promises
* add incref's all around to make sure we aren't freeing objects early
* make it so we return PyPromises everywhere and make chains collapsible

test/test_rpc.py

@@ -12,17 +12,60 @@ class Server(test_capability_capnp.TestInterface.Server):
     def foo(self, i, j, **kwargs):
         return str(i * 5 + self.val)
 
-def test_simple_rpc():
-    def _restore(ref_id):
+class TypelessRestorer:
+    def restore(self, ref_id):
         return Server(100)
 
+def restore_func(ref_id):
+    return Server(100)
+
+class SimpleRestorer(test_capability_capnp.TestSturdyRefObjectId.Restorer):
+    def restore(self, ref_id):
+        assert ref_id.tag == 'testInterface'
+        return Server(100)
+
+def test_simple_rpc():
+
     read, write = socket.socketpair(socket.AF_UNIX)
 
-    restorer = capnp.Restorer(test_capability_capnp.TestSturdyRefObjectId, _restore)
-    server = capnp.RpcServer(write, restorer)
-    client = capnp.RpcClient(read)
+    restorer = SimpleRestorer()
+    server = capnp.TwoPartyServer(write, restorer)
+    client = capnp.TwoPartyClient(read)
 
-    ref = test_capability_capnp.TestSturdyRefObjectId.new_message()
+    ref = test_capability_capnp.TestSturdyRefObjectId.new_message(tag='testInterface')
+    cap = client.restore(ref)
+    cap = cap.cast_as(test_capability_capnp.TestInterface)
+
+    remote = cap.foo(i=5)
+    response = remote.wait()
+
+    assert response.x == '125'
+
+def test_simple_rpc_typeless_restorer():
+
+    read, write = socket.socketpair(socket.AF_UNIX)
+
+    restorer = TypelessRestorer()
+    server = capnp.TwoPartyServer(write, restorer)
+    client = capnp.TwoPartyClient(read)
+
+    ref = test_capability_capnp.TestSturdyRefObjectId.new_message(tag='testInterface')
+    cap = client.restore(ref)
+    cap = cap.cast_as(test_capability_capnp.TestInterface)
+
+    remote = cap.foo(i=5)
+    response = remote.wait()
+
+    assert response.x == '125'
+
+def test_simple_rpc_restore_func():
+
+    read, write = socket.socketpair(socket.AF_UNIX)
+
+    server = capnp.TwoPartyServer(write, restore_func)
+    client = capnp.TwoPartyClient(read)
+
+    ref = test_capability_capnp.TestSturdyRefObjectId.new_message(tag='testInterface')
     cap = client.restore(ref)
     cap = cap.cast_as(test_capability_capnp.TestInterface)