metrics: add url shortener counters

app/metrics.py

@@ -14,6 +14,9 @@ _paste_deleted_counter = None
 _rate_limit_counter = None
 _pow_counter = None
 _dedup_counter = None
+_url_created_counter = None
+_url_accessed_counter = None
+_url_deleted_counter = None
 _request_duration_histogram = None
 
 
@@ -23,7 +26,9 @@ def setup_custom_metrics(app: Flask) -> None:
     Should be called after prometheus_flask_exporter is set up.
     """
     global _paste_created_counter, _paste_accessed_counter, _paste_deleted_counter
-    global _rate_limit_counter, _pow_counter, _dedup_counter, _request_duration_histogram
+    global _rate_limit_counter, _pow_counter, _dedup_counter
+    global _url_created_counter, _url_accessed_counter, _url_deleted_counter
+    global _request_duration_histogram
 
     if app.config.get("TESTING"):
         return
@@ -70,6 +75,24 @@ def setup_custom_metrics(app: Flask) -> None:
         ["outcome"],
     )
 
+    _url_created_counter = Counter(
+        "flaskpaste_url_created_total",
+        "Total number of short URL creation attempts",
+        ["auth_type", "outcome"],
+    )
+
+    _url_accessed_counter = Counter(
+        "flaskpaste_url_accessed_total",
+        "Total number of short URL accesses",
+        ["auth_type"],
+    )
+
+    _url_deleted_counter = Counter(
+        "flaskpaste_url_deleted_total",
+        "Total number of short URL deletion attempts",
+        ["auth_type", "outcome"],
+    )
+
     _request_duration_histogram = Histogram(
         "flaskpaste_request_duration_seconds",
         "Request duration in seconds",
@@ -143,6 +166,24 @@ def record_dedup(outcome: str) -> None:
         _dedup_counter.labels(outcome=outcome).inc()
 
 
+def record_url_created(auth_type: str, outcome: str) -> None:
+    """Record a short URL creation attempt."""
+    if _url_created_counter:
+        _url_created_counter.labels(auth_type=auth_type, outcome=outcome).inc()
+
+
+def record_url_accessed(auth_type: str) -> None:
+    """Record a short URL access."""
+    if _url_accessed_counter:
+        _url_accessed_counter.labels(auth_type=auth_type).inc()
+
+
+def record_url_deleted(auth_type: str, outcome: str) -> None:
+    """Record a short URL deletion attempt."""
+    if _url_deleted_counter:
+        _url_deleted_counter.labels(auth_type=auth_type, outcome=outcome).inc()
+
+
 def observe_request_duration(method: str, endpoint: str, status: int, duration: float) -> None:
     """Record request duration.