Add prometheus metrics endpoint. Closes #67

core/prometheus_metrics_handler.py

@@ -0,0 +1,40 @@
+from bottle import response
+from prometheus_client import CollectorRegistry, generate_latest, CONTENT_TYPE_LATEST, Counter, disable_created_metrics, \
+    Gauge
+
+disable_created_metrics()
+# Prometheus metrics registry
+registry = CollectorRegistry()
+
+page_requests_counter = Counter(
+    "page_requests",
+    "Total number of page requests received",
+    registry=registry,
+)
+api_requests_counter = Counter(
+    "api_requests",
+    "Total number of API requests received",
+    registry=registry
+)
+spots_gauge = Gauge(
+    "spots",
+    "Number of spots currently in the software",
+    registry=registry
+)
+alerts_gauge = Gauge(
+    "alerts",
+    "Number of alerts currently in the software",
+    registry=registry
+)
+memory_use_gauge = Gauge(
+    "memory_usage_bytes",
+    "Current memory usage of the software in bytes",
+    registry=registry
+)
+
+
+# Get a Prometheus metrics response for Bottle
+def get_metrics():
+    response.content_type = CONTENT_TYPE_LATEST
+    response.status = 200
+    return generate_latest(registry)