Protocol muxing (#82)

* Implement protocol muxing

* Integrate protocol muxing into new stream and listen's conn handler

* Fix bugs in protocol muxing

* Remove blank line

* Add comments and fix linting issues

* Fix order of parameters to select_one_of to match interface

* Use array of protocol ids in new stream instead of protocol id

* Add basic protocol muxer tests

* Add todo

* Modify new stream to take in protocol ids

* Add check to all tests to ensure protocol id is saved to net stream properly

* Lint tests

* Fix lint issues

* Add todo

* Modify port numbers in tests

* Fix linting issues

* Add more documentation to functions

* Add docs describing classes and fix indent error

tests/libp2p/test_libp2p.py

@@ -20,8 +20,10 @@ async def test_simple_messages():
 
     # Associate the peer with local ip address (see default parameters of Libp2p())
     node_a.get_peerstore().add_addr("node_b", "/ip4/127.0.0.1/tcp/8000", 10)
+
     print("node_a about to open stream")
-    stream = await node_a.new_stream("node_b", "/echo/1.0.0")
+    stream = await node_a.new_stream("node_b", ["/echo/1.0.0"])
+
     messages = ["hello" + str(x) for x in range(10)]
     for message in messages:
         await stream.write(message.encode())
@@ -57,7 +59,7 @@ async def test_double_response():
     # Associate the peer with local ip address (see default parameters of Libp2p())
     node_a.get_peerstore().add_addr("node_b", "/ip4/127.0.0.1/tcp/8003", 10)
     print("node_a about to open stream")
-    stream = await node_a.new_stream("node_b", "/echo/1.0.0")
+    stream = await node_a.new_stream("node_b", ["/echo/1.0.0"])
     messages = ["hello" + str(x) for x in range(10)]
     for message in messages:
         await stream.write(message.encode())

tests/protocol_muxer/test_protocol_muxer.py

@@ -0,0 +1,88 @@
+import pytest
+
+from libp2p.libp2p import new_node
+from protocol_muxer.multiselect_client import MultiselectClientError
+
+# TODO: Add tests for multiple streams being opened on different
+# protocols through the same connection
+
+# Note: async issues occurred when using the same port
+# so that's why I use different ports here.
+# TODO: modify tests so that those async issues don't occur
+# when using the same ports across tests
+
+async def perform_simple_test(expected_selected_protocol, \
+    protocols_for_client, protocols_with_handlers, \
+    node_a_port, node_b_port):
+    transport_opt_a = ["/ip4/127.0.0.1/tcp/" + str(node_a_port) + "/ipfs/node_a"]
+    transport_opt_b = ["/ip4/127.0.0.1/tcp/" + str(node_b_port) + "/ipfs/node_b"]
+    node_a = await new_node(\
+        transport_opt=transport_opt_a)
+    node_b = await new_node(\
+        transport_opt=transport_opt_b)
+
+    async def stream_handler(stream):
+        while True:
+            read_string = (await stream.read()).decode()
+            print("host B received:" + read_string)
+
+            response = "ack:" + read_string
+            print("sending response:" + response)
+            await stream.write(response.encode())
+
+    for protocol in protocols_with_handlers:
+        node_b.set_stream_handler(protocol, stream_handler)
+
+    # Associate the peer with local ip address (see default parameters of Libp2p())
+    node_a.get_peerstore().add_addr("node_b", "/ip4/127.0.0.1/tcp/" + str(node_b_port), 10)
+
+    stream = await node_a.new_stream("node_b", protocols_for_client)
+    messages = ["hello" + str(x) for x in range(10)]
+    for message in messages:
+        await stream.write(message.encode())
+
+        response = (await stream.read()).decode()
+
+        print("res: " + response)
+        assert response == ("ack:" + message)
+
+    assert expected_selected_protocol == stream.get_protocol()
+
+    # Success, terminate pending tasks.
+    return
+
+@pytest.mark.asyncio
+async def test_single_protocol_succeeds():
+    expected_selected_protocol = "/echo/1.0.0"
+    await perform_simple_test(expected_selected_protocol, \
+        ["/echo/1.0.0"], ["/echo/1.0.0"], 8050, 8051)
+
+@pytest.mark.asyncio
+async def test_single_protocol_fails():
+    with pytest.raises(MultiselectClientError):
+        await perform_simple_test("", ["/echo/1.0.0"], \
+            ["/potato/1.0.0"], 8052, 8053)
+
+@pytest.mark.asyncio
+async def test_multiple_protocol_first_is_valid_succeeds():
+    expected_selected_protocol = "/echo/1.0.0"
+    protocols_for_client = ["/echo/1.0.0", "/potato/1.0.0"]
+    protocols_for_listener = ["/foo/1.0.0", "/echo/1.0.0"]
+    await perform_simple_test(expected_selected_protocol, protocols_for_client, \
+        protocols_for_listener, 8054, 8055)
+
+@pytest.mark.asyncio
+async def test_multiple_protocol_second_is_valid_succeeds():
+    expected_selected_protocol = "/foo/1.0.0"
+    protocols_for_client = ["/rock/1.0.0", "/foo/1.0.0"]
+    protocols_for_listener = ["/foo/1.0.0", "/echo/1.0.0"]
+    await perform_simple_test(expected_selected_protocol, protocols_for_client, \
+        protocols_for_listener, 8056, 8057)
+
+@pytest.mark.asyncio
+async def test_multiple_protocol_fails():
+    protocols_for_client = ["/rock/1.0.0", "/foo/1.0.0", "/bar/1.0.0"]
+    protocols_for_listener = ["/aspyn/1.0.0", "/rob/1.0.0", "/zx/1.0.0", "/alex/1.0.0"]
+    with pytest.raises(MultiselectClientError):
+        await perform_simple_test("", protocols_for_client, \
+            protocols_for_listener, 8058, 8059)