Create script for monitoring GTFS-RT feeds

gtfsrt_data_collector.py

@@ -0,0 +1,72 @@
+from google.transit import gtfs_realtime_pb2
+import requests
+import time
+import json
+from datetime import datetime
+import os
+from dotenv import load_dotenv
+from send_data_to_azure_monitor import send_custom_metrics_request
+
+load_dotenv()
+
+IS_DEBUG = os.getenv('IS_DEBUG') == "True"
+
+def get_stats(url):
+    feed = gtfs_realtime_pb2.FeedMessage()
+    response = requests.get(url)
+    feed.ParseFromString(response.content)
+
+    num_entities = len(feed.entity)
+    time_diff = round(time.time()) - feed.header.timestamp
+
+    return (num_entities, time_diff)
+
+def send_data_to_azure_monitor(time, metric, url, value):
+    time_str = time.strftime("%Y-%m-%dT%H:%M:%S")
+
+    custom_metric_object = {
+        # Time (timestamp): Date and time at which the metric is measured or collected
+        "time": time_str,
+        "data": {
+            "baseData": {
+                # Metric (name): name of the metric
+                "metric": metric,
+                # Namespace: Categorize or group similar metrics together
+                "namespace": "GTFSRT",
+                # Dimension (dimNames): Metric has a single dimension
+                "dimNames": [
+                  "URL"
+                ],
+                # Series: data for each monitored topic
+                "series": [
+                    {
+                        "dimValues": [
+                            url
+                        ],
+                        "sum": value,
+                        "count": 1
+                    }
+                ]
+            }
+        }
+    }
+
+    custom_metric_json = json.dumps(custom_metric_object)
+
+    if IS_DEBUG:
+        print(custom_metric_json)
+    else:
+        send_custom_metrics_request(custom_metric_json, 3)
+
+def main():
+    urls = os.getenv("GTFSRT_URLS").split(",")
+    for url in urls:
+        (entity_count, last_published_ago_secs) = get_stats(url)
+
+        time = datetime.utcnow()
+
+        send_data_to_azure_monitor(time, "Entity Count", url, entity_count)
+        send_data_to_azure_monitor(time, "Timestamp Age", url, last_published_ago_secs)
+
+if __name__ == '__main__':
+    main()

requirements.txt

@@ -1,2 +1,3 @@
 paho-mqtt==1.6.1
 python-dotenv==0.20.0
+gtfs-realtime-bindings==0.0.7