[Add] Add trader mainengine

vnpy/trader/engine.py

@@ -0,0 +1,83 @@
+"""
+"""
+
+from vnpy.event import EventEngine, Event
+
+from .event import EVENT_LOG
+from .object import LogData, SubscribeRequest, OrderRequest, CancelRequest
+
+
+class MainEngine:
+    """
+    Acts as the core of VN Trader.
+    """
+
+    def __init__(self, event_engine: EventEngine = None):
+        """"""
+        if event_engine:
+            self.event_engine = event_engine
+        else:
+            self.event_engine = EventEngine()
+        self.event_engine.start()
+
+        self.gateways = {}
+        self.apps = {}
+
+    def write_log(self, msg: str):
+        """
+        Put log event with specific message.
+        """
+        log = LogData(msg=msg)
+        event = Event(EVENT_LOG, log)
+        self.event_engine.put(event)
+
+    def get_gateway(gateway_name: str):
+        """
+        Return gateway object by name.
+        """
+        gateway = self.gateways.get(gateway_name, None)
+        if not gateway:
+            self.write_log(f"找不到底层接口：{gateway_name}")
+        return gateway
+
+    def connect(self, gateway_name: str):
+        """
+        Start connection of a specific gateway.
+        """
+        gateway = self.get_gateway(gateway_name)
+        if gateway:
+            gateway.connect()
+
+    def subscribe(self, req: SubscribeRequest, gateway_name: str):
+        """
+        Subscribe tick data update of a specific gateway.
+        """
+        gateway = self.get_gateway(gateway_name)
+        if gateway:
+            gateway.subscribe(req)
+
+    def send_order(self, req: OrderRequest, gateway_name: str):
+        """
+        Send new order request to a specific gateway.
+        """
+        gateway = self.get_gateway(gateway_name)
+        if gateway:
+            gateway.send_order(req)
+
+    def cancel_order(self, req: CancelRequest, gateway_name: str):
+        """
+        Send cancel order request to a specific gateway.
+        """
+        gateway = self.get_gateway(gateway_name)
+        if gateway:
+            gateway.send_order(req)
+
+    def close(self):
+        """
+        Make sure every gateway and app is closed properly before
+        programme exit.
+        """
+        for gateway in self.gateways.values():
+            gateway.close()
+
+        self.event_engine.stop()