Feature/wikipedia ddg (#185)

API-side support for Wikipedia, DBpedia and internet search functions  This incorporates a refactor of the API code to break it up, separate classes for endpoints to reduce duplication

trustgraph-flow/trustgraph/api/gateway/socket.py

@@ -0,0 +1,68 @@
+
+import asyncio
+from aiohttp import web, WSMsgType
+import logging
+
+from . running import Running
+
+logger = logging.getLogger("socket")
+logger.setLevel(logging.INFO)
+
+class SocketEndpoint:
+
+    def __init__(
+            self,
+            endpoint_path="/api/v1/socket",
+    ):
+
+        self.path = endpoint_path
+
+    async def listener(self, ws, running):
+        
+        async for msg in ws:
+            # On error, finish
+            if msg.type == WSMsgType.ERROR:
+                break
+            else:
+                # Ignore incoming messages
+                pass
+
+        running.stop()
+
+    async def async_thread(self, ws, running):
+
+        while running.get():
+            try:
+                await asyncio.sleep(1)
+
+            except TimeoutError:
+                continue
+
+            except Exception as e:
+                print(f"Exception: {str(e)}", flush=True)
+        
+    async def handle(self, request):
+
+        running = Running()
+        ws = web.WebSocketResponse()
+        await ws.prepare(request)
+
+        task = asyncio.create_task(self.async_thread(ws, running))
+
+        await self.listener(ws, running)
+
+        await task
+
+        running.stop()
+
+        return ws
+
+    async def start(self):
+        pass
+
+    def add_routes(self, app):
+
+        app.add_routes([
+            web.get(self.path, self.handle),
+        ])
+