add hostname to the labels of the metrics; pull out calls to metrics file

Signed-off-by: Mike Kingsbury <[email protected]>

Author: mike-kingsbury

cachito/web/api_v1.py

@@ -25,7 +25,7 @@
 from cachito.errors import MessageBrokerError, NoWorkers, RequestErrorOrigin, ValidationError
 from cachito.web import db
 from cachito.web.content_manifest import BASE_ICM
-from cachito.web.metrics import cachito_metrics
+from cachito.web.metrics import cachito_metrics, requests_dec, requests_inc
 from cachito.web.models import (
     ConfigFileBase64,
     EnvironmentVariable,
@@ -337,8 +337,8 @@ def create_request():
     db.session.add(request)
     db.session.commit()
 
-    cachito_metrics["gauge_state"].labels(state="total").inc()
-    cachito_metrics["gauge_state"].labels(state=request.state.state_name).inc()
+    requests_inc("total")
+    requests_inc(request.state.state_name)
 
     if current_user.is_authenticated:
         flask.current_app.logger.info(
@@ -438,9 +438,9 @@ def create_request():
             "Failed to schedule the task for request %d. Failing the request.", request.id
         )
         error = "Failed to schedule the task to the workers. Please try again."
-        cachito_metrics["gauge_state"].labels(state=request.state.state_name).dec()
+        requests_dec(request.state.state_name)
         request.add_state("failed", error)
-        cachito_metrics["gauge_state"].labels(state=request.state.state_name).inc()
+        requests_inc(request.state.state_name)
         db.session.commit()
         raise MessageBrokerError(error)
 
@@ -525,8 +525,8 @@ def patch_request(request_id):
     delete_logs = False
 
     if "state" in payload and "state_reason" in payload:
-        cachito_metrics["gauge_state"].labels(state=payload["state"]).inc()
-        cachito_metrics["gauge_state"].labels(state=request.state.state_name).dec()
+        requests_inc(payload["state"])
+        requests_dec(request.state.state_name)
         new_state = payload["state"]
         delete_bundle = new_state == "stale" and request.state.state_name != "failed"
         if new_state in ("stale", "failed"):

cachito/web/metrics.py

@@ -6,6 +6,7 @@
 from prometheus_flask_exporter.multiprocess import GunicornInternalPrometheusMetrics
 
 cachito_metrics = {}
+hostname = socket.gethostname()
 
 
 def init_metrics(app):
@@ -17,7 +18,6 @@ def init_metrics(app):
     """
     registry = CollectorRegistry()
     multiproc_temp_dir = app.config["PROMETHEUS_METRICS_TEMP_DIR"]
-    hostname = socket.gethostname()
 
     if not os.path.isdir(multiproc_temp_dir):
         os.makedirs(multiproc_temp_dir)
@@ -27,10 +27,23 @@ def init_metrics(app):
     )
     metrics.init_app(app)
     gauge_state = Gauge(
-        "cachito_requests_count", "Requests in each state", ["state"], multiprocess_mode="livesum"
+        "cachito_requests_count",
+        "Requests in each state",
+        ["state", "host"],
+        multiprocess_mode="livesum",
     )
     request_duration = Summary(
         "cachito_request_duration_seconds", "Time spent in in_progress state"
     )
     cachito_metrics["gauge_state"] = gauge_state
     cachito_metrics["request_duration"] = request_duration
+
+
+def requests_inc(state):
+    """Increase the number of requests in given state."""
+    cachito_metrics["gauge_state"].labels(state=state, host=hostname).inc()
+
+
+def requests_dec(state):
+    """Decrease the number of requests in the given state."""
+    cachito_metrics["gauge_state"].labels(state=state, host=hostname).dec()