Import source: axon/services/metrics

Import the existing local project snapshot. This commit organizes existing files; it does not represent newly developed functionality.

axon/services/metrics.py

@@ -0,0 +1,36 @@
+import asyncio
+from collections import defaultdict
+
+
+class MetricsRegistry:
+    def __init__(self) -> None:
+        self._lock = asyncio.Lock()
+        self.requests_total = 0
+        self.errors_total = 0
+        self.latency_total_ms = 0.0
+        self.requests_by_path: dict[str, int] = defaultdict(int)
+
+    async def record(self, path: str, status_code: int, latency_ms: float) -> None:
+        async with self._lock:
+            self.requests_total += 1
+            self.requests_by_path[path] += 1
+            self.latency_total_ms += latency_ms
+            if status_code >= 500:
+                self.errors_total += 1
+
+    async def snapshot(self) -> dict:
+        async with self._lock:
+            average = (
+                self.latency_total_ms / self.requests_total
+                if self.requests_total
+                else 0.0
+            )
+            return {
+                "requests_total": self.requests_total,
+                "requests_by_path": dict(self.requests_by_path),
+                "errors_total": self.errors_total,
+                "average_latency_ms": round(average, 3),
+            }
+
+
+metrics = MetricsRegistry()