langserver.py: Update to use jsonrpc

.codecov.yml

@@ -6,4 +6,4 @@ coverage:
     project:
       default:
         enabled: true
-        target: 83%
+        target: 95%

coala_langserver/langserver.py

@@ -3,62 +3,52 @@
 import socketserver
 import traceback
 
-from .jsonrpc import JSONRPC2Connection, ReadWriter, TCPReadWriter
+from pyls.jsonrpc.endpoint import Endpoint
+from pyls.jsonrpc.dispatchers import MethodDispatcher
+from pyls.jsonrpc.streams import JsonRpcStreamReader
+from pyls.jsonrpc.streams import JsonRpcStreamWriter
+from coala_utils.decorators import enforce_signature
 from .log import log
 from .coalashim import run_coala_with_specific_file
 from .uri import path_from_uri
 from .diagnostic import output_to_diagnostics
 
 
-class ThreadingTCPServer(socketserver.ThreadingMixIn, socketserver.TCPServer):
-    pass
+class _StreamHandlerWrapper(socketserver.StreamRequestHandler, object):
+    """
+    A wrapper class that is used to construct a custom handler class.
+    """
 
+    delegate = None
 
-class LangserverTCPTransport(socketserver.StreamRequestHandler):
+    def setup(self):
+        super(_StreamHandlerWrapper, self).setup()
+        self.delegate = self.DELEGATE_CLASS(self.rfile, self.wfile)
 
     def handle(self):
-        s = LangServer(conn=TCPReadWriter(self.rfile, self.wfile))
-        try:
-            s.listen()
-        except Exception as e:
-            tb = traceback.format_exc()
-            log('ERROR: {} {}'.format(e, tb))
+        self.delegate.start()
 
 
-class LangServer(JSONRPC2Connection):
+class LangServer(MethodDispatcher):
     """
     Language server for coala base on JSON RPC.
     """
 
-    def __init__(self, conn=None):
-        super().__init__(conn=conn)
+    def __init__(self, rx, tx):
         self.root_path = None
+        self._jsonrpc_stream_reader = JsonRpcStreamReader(rx)
+        self._jsonrpc_stream_writer = JsonRpcStreamWriter(tx)
+        self._endpoint = Endpoint(self, self._jsonrpc_stream_writer.write)
+        self._dispatchers = []
+        self._shutdown = False
 
-    def handle(self, _id, request):
-        """
-        Handle the request from language client.
-        """
-        log('REQUEST: ', request)
-        resp = None
-
-        if request['method'] == 'initialize':
-            resp = self.serve_initialize(request)
-        # TODO: Support did_change and did_change_watched_files.
-        # elif request["method"] == "textDocument/didChange":
-        #     resp = self.serve_change(request)
-        # elif request["method"] == "workspace/didChangeWatchedFiles":
-        #     resp = self.serve_did_change_watched_files(request)
-        elif request['method'] == 'textDocument/didSave':
-            self.serve_did_save(request)
-
-        if resp is not None:
-            self.write_response(request['id'], resp)
-
-    def serve_initialize(self, request):
+    def start(self):
+        self._jsonrpc_stream_reader.listen(self._endpoint.consume)
+
+    def m_initialize(self, **params):
         """
         Serve for the initialization request.
         """
-        params = request['params']
         # Notice that the root_path could be None.
         if 'rootUri' in params:
             self.root_path = path_from_uri(params['rootUri'])
@@ -70,17 +60,19 @@ def serve_initialize(self, request):
             }
         }
 
-    def serve_did_save(self, request):
+    def m_text_document__did_save(self, **params):
         """
         Serve for did_change request.
         """
-        params = request['params']
         uri = params['textDocument']['uri']
         path = path_from_uri(uri)
         diagnostics = output_to_diagnostics(
             run_coala_with_specific_file(self.root_path, path))
         self.send_diagnostics(path, diagnostics)
 
+    def m_shutdown(self, **_kwargs):
+        self._shutdown = True
+
     # TODO: Support did_change and did_change_watched_files.
     # def serve_change(self, request):
     #     '""Serve for the request of documentation changed.""'
@@ -110,7 +102,38 @@ def send_diagnostics(self, path, diagnostics):
             'uri': 'file://{0}'.format(path),
             'diagnostics': _diagnostics,
         }
-        self.send_notification('textDocument/publishDiagnostics', params)
+        self._endpoint.notify('textDocument/publishDiagnostics', params=params)
+
+
+@enforce_signature
+def start_tcp_lang_server(handler_class: LangServer, bind_addr, port):
+    # Construct a custom wrapper class around the user's handler_class
+    wrapper_class = type(
+        handler_class.__name__ + 'Handler',
+        (_StreamHandlerWrapper,),
+        {'DELEGATE_CLASS': handler_class},
+    )
+
+    try:
+        server = socketserver.TCPServer((bind_addr, port), wrapper_class)
+    except Exception as e:
+        log('Fatal Exception: {}'.format(e))
+        sys.exit(1)
+
+    log('Serving {} on ({}, {})'.format(
+        handler_class.__name__, bind_addr, port))
+    try:
+        server.serve_forever()
+    finally:
+        log('Shutting down')
+        server.server_close()
+
+
+@enforce_signature
+def start_io_lang_server(handler_class: LangServer, rstream, wstream):
+    log('Starting {} IO language server'.format(handler_class.__name__))
+    server = handler_class(rstream, wstream)
+    server.start()
 
 
 def main():
@@ -123,18 +146,10 @@ def main():
     args = parser.parse_args()
 
     if args.mode == 'stdio':
-        log('Reading on stdin, writing on stdout')
-        s = LangServer(conn=ReadWriter(sys.stdin, sys.stdout))
-        s.listen()
+        start_io_lang_server(LangServer, sys.stdin.buffer, sys.stdout.buffer)
     elif args.mode == 'tcp':
         host, addr = '0.0.0.0', args.addr
-        log('Accepting TCP connections on {}:{}'.format(host, addr))
-        ThreadingTCPServer.allow_reuse_address = True
-        s = ThreadingTCPServer((host, addr), LangserverTCPTransport)
-        try:
-            s.serve_forever()
-        finally:
-            s.shutdown()
+        start_tcp_lang_server(LangServer, host, addr)
 
 
 if __name__ == '__main__':

requirements.txt

@@ -1,3 +1,4 @@
 coala>=0.10.0.dev20170213201648
 typing>=3.5.3.0
 coala-bears>=0.10.0.dev20170215041744
+python-language-server~=0.18.0

tests/server.features/jsonrpc.feature

@@ -1,35 +1,20 @@
 Feature: jsonrpc module
   jsonrpc is a module of language-server.
 
-  Scenario: Test ReadWriter
-    Given the string
-    When I write it to ReadWriter
-    Then it should read from ReadWriter
+  Scenario: Test JsonRpcStreamWriter and JsonRpcStreamReader
+    Given the message
+    When I write it to JsonRpcStreamWriter
+    Then it should read from JsonRpcStreamReader
 
-  Scenario: Test ReadWriter
-    Given the string
-    When I write it to ReadWriter
-    Then it should readline from ReadWriter
+  Scenario: Test notification and disptacher
+    Given a notification type rpc request
+    When I send rpc request using JsonRpcStreamWriter
+    Then it should invoke the notification consumer with args
 
-  Scenario: Test TCPReadWriter
-    Given the string
-    When I write it to TCPReadWriter
-    Then it should read from TCPReadWriter
-
-  Scenario: Test TCPReadWriter
-    Given the string
-    When I write it to TCPReadWriter
-    Then it should readline from TCPReadWriter
-
-  Scenario: Test send_notification and read_message
-    Given the JSONRPC2Connection instance
-    When I write a notification to the JSONRPC2Connection
-    Then it should return the notification from JSONRPC2Connection
-
-  Scenario: Test write_response
-    Given the JSONRPC2Connection instance
-    When I write a response to the JSONRPC2Connection
-    Then it should return the response from JSONRPC2Connection
+  Scenario: Test rpc request and response
+    Given a request type rpc request
+    When I send rpc request using JsonRpcStreamWriter
+    Then it should invoke consumer and return response
 
   # TODO: block until we have generantee the unique request.
 #  Scenario: Test send_request