added first version of a broker request status monitor

slic/core/acquisition/broker/requeststatus.py

@@ -0,0 +1,117 @@
+import json
+from datetime import datetime
+from threading import Thread
+
+from pika import BlockingConnection, ConnectionParameters
+
+
+DEFAULT_BROKER_URL = "sf-daq"
+STATUS_EXCHANGE = "status"
+
+
+class RequestStatus:
+
+    ENTRIES = (
+        "announced",
+        "started",
+        "success",
+        "failure",
+        "ghosts"
+    )
+
+
+    def __init__(self, broker_url=DEFAULT_BROKER_URL):
+        self.broker_url = broker_url
+
+        for i in self.ENTRIES:
+            setattr(self, i, {})
+
+        self.thread = thread = Thread(target=self._run)
+        thread.daemon = True
+        thread.start()
+
+
+    def clear(self):
+        for i in self.ENTRIES:
+            getattr(self, i).clear()
+
+
+    def _run(self):
+        connection = BlockingConnection(ConnectionParameters(self.broker_url))
+
+        channel = connection.channel()
+        channel.exchange_declare(exchange=STATUS_EXCHANGE, exchange_type="fanout")
+
+        queue = channel.queue_declare(queue="", exclusive=True).method.queue
+        channel.queue_bind(queue=queue, exchange=STATUS_EXCHANGE)
+        channel.basic_consume(queue, self._on_status, auto_ack=True)
+
+        try:
+            channel.start_consuming()
+        except KeyboardInterrupt:
+            channel.stop_consuming()
+
+
+    def _on_status(self, _channel, _method_frame, header_frame, body):
+        correlation_id = header_frame.correlation_id
+        headers        = header_frame.headers
+        timestamp      = header_frame.timestamp
+
+        body = body.decode()
+        request = json.loads(body)
+
+        action = headers["action"]
+
+        timestamp = datetime.fromtimestamp(timestamp / 1e9)
+
+        key = correlation_id.split("-", 1)[0]
+
+        #TODO: nicely pack the information
+        data = {
+            "timestamp": timestamp,
+            "headers": headers,
+            "request": request
+        }
+
+        if action == "write_request":
+            self.announced[key] = data
+        elif action == "write_start":
+            if key in self.announced:
+                self.announced.pop(key)
+                self.started[key] = data
+            else:
+                self.ghosts[key] = data
+        elif action == "write_finished":
+            if key in self.started:
+                self.started.pop(key)
+                self.success[key] = data
+            else:
+                self.ghosts[key] = data
+        elif  action == "write_rejected":
+            if key in self.started:
+                self.started.pop(key)
+                self.failure[key] = data
+            else:
+                self.ghosts[key] = data
+
+
+    def __repr__(self):
+        header = "Request Status:"
+        underline = "-" * len(header)
+        res = [header, underline]
+
+        maxlen = max(len(i) for i in self.ENTRIES)
+        entries = {f"{i}:".ljust(maxlen+1): len(getattr(self, i)) for i in self.ENTRIES}
+        res += [f"{k} {v}" for k, v in entries.items()]
+
+        res = "\n".join(res)
+        return res
+
+
+
+
+
+if __name__ == "__main__":
+    rs = RequestStatus()
+
+