feat(server): sync data with ack (#4791)

packages/backend/server/src/metrics/utils.ts

@@ -1,4 +1,8 @@
-import { Counter, Gauge, Summary } from 'prom-client';
+import { Counter, Gauge, register, Summary } from 'prom-client';
+
+function getOr<T>(name: string, or: () => T): T {
+  return (register.getSingleMetric(name) as T) || or();
+}
 
 type LabelValues<T extends string> = Partial<Record<T, string | number>>;
 type MetricsCreator<T extends string> = (
@@ -14,11 +18,15 @@ export const metricsCreatorGenerator = () => {
     name: string,
     labelNames?: T[]
   ): MetricsCreator<T> => {
-    const counter = new Counter({
+    const counter = getOr(
       name,
-      help: name,
-      ...(labelNames ? { labelNames } : {}),
-    });
+      () =>
+        new Counter({
+          name,
+          help: name,
+          ...(labelNames ? { labelNames } : {}),
+        })
+    );
 
     return (value: number, labels: LabelValues<T>) => {
       counter.inc(labels, value);
@@ -29,11 +37,15 @@ export const metricsCreatorGenerator = () => {
     name: string,
     labelNames?: T[]
   ): MetricsCreator<T> => {
-    const gauge = new Gauge({
+    const gauge = getOr(
       name,
-      help: name,
-      ...(labelNames ? { labelNames } : {}),
-    });
+      () =>
+        new Gauge({
+          name,
+          help: name,
+          ...(labelNames ? { labelNames } : {}),
+        })
+    );
 
     return (value: number, labels: LabelValues<T>) => {
       gauge.set(labels, value);
@@ -44,11 +56,15 @@ export const metricsCreatorGenerator = () => {
     name: string,
     labelNames?: T[]
   ): TimerMetricsCreator<T> => {
-    const summary = new Summary({
+    const summary = getOr(
       name,
-      help: name,
-      ...(labelNames ? { labelNames } : {}),
-    });
+      () =>
+        new Summary({
+          name,
+          help: name,
+          ...(labelNames ? { labelNames } : {}),
+        })
+    );
 
     return (labels: LabelValues<T>) => {
       const now = process.hrtime();
@@ -71,3 +87,68 @@ export const metricsCreatorGenerator = () => {
 };
 
 export const metricsCreator = metricsCreatorGenerator();
+
+export const CallTimer = (
+  name: string,
+  labels: Record<string, any> = {}
+): MethodDecorator => {
+  const timer = metricsCreator.timer(name, Object.keys(labels));
+
+  // @ts-expect-error allow
+  return (
+    _target,
+    _key,
+    desc: TypedPropertyDescriptor<(...args: any[]) => any>
+  ) => {
+    const originalMethod = desc.value;
+    if (!originalMethod) {
+      return desc;
+    }
+
+    desc.value = function (...args: any[]) {
+      const endTimer = timer(labels);
+      let result: any;
+      try {
+        result = originalMethod.apply(this, args);
+      } catch (e) {
+        endTimer();
+        throw e;
+      }
+
+      if (result instanceof Promise) {
+        return result.finally(endTimer);
+      } else {
+        endTimer();
+        return result;
+      }
+    };
+
+    return desc;
+  };
+};
+
+export const CallCounter = (
+  name: string,
+  labels: Record<string, any> = {}
+): MethodDecorator => {
+  const count = metricsCreator.counter(name, Object.keys(labels));
+
+  // @ts-expect-error allow
+  return (
+    _target,
+    _key,
+    desc: TypedPropertyDescriptor<(...args: any[]) => any>
+  ) => {
+    const originalMethod = desc.value;
+    if (!originalMethod) {
+      return desc;
+    }
+
+    desc.value = function (...args: any[]) {
+      count(1, labels);
+      return originalMethod.apply(this, args);
+    };
+
+    return desc;
+  };
+};