chore: update prometheus examples

.github/workflows/unit-test.yml

@@ -33,7 +33,7 @@ jobs:
             packages/*/package-lock.json
             experimental/packages/*/node_modules
             experimental/packages/*/package-lock.json
-          key: node-tests-${{ runner.os }}-${{ matrix.node_version }}-${{ hashFiles('package.json', 'packages/*/package.json', 'experimental/packages/*/package.json') }}-04142022
+          key: node-tests-${{ runner.os }}-${{ matrix.node_version }}-${{ hashFiles('package.json', 'packages/*/package.json', 'experimental/packages/*/package.json') }}-04292022
 
       - name: Bootstrap
         run: |
@@ -72,7 +72,7 @@ jobs:
             packages/*/package-lock.json
             experimental/packages/*/node_modules
             experimental/packages/*/package-lock.json
-          key: browser-tests-${{ runner.os }}-${{ hashFiles('package.json', 'packages/*/package.json', 'experimental/packages/*/package.json') }}-04142022
+          key: browser-tests-${{ runner.os }}-${{ hashFiles('package.json', 'packages/*/package.json', 'experimental/packages/*/package.json') }}-04292022
 
       - name: Bootstrap
         run: |
@@ -112,7 +112,7 @@ jobs:
             packages/*/package-lock.json
             experimental/packages/*/node_modules
             experimental/packages/*/package-lock.json
-          key: webworker-tests-${{ runner.os }}-${{ hashFiles('package.json', 'packages/*/package.json', 'experimental/packages/*/package.json') }}-04142022
+          key: webworker-tests-${{ runner.os }}-${{ hashFiles('package.json', 'packages/*/package.json', 'experimental/packages/*/package.json') }}-04292022
 
       - name: Bootstrap
         run: |

experimental/examples/.eslintrc.js

@@ -0,0 +1,7 @@
+module.exports = {
+  "env": {
+      "mocha": true,
+      "node": true
+  },
+  ...require('../../eslint.config.js')
+}

examples/prometheus/index.js → experimental/examples/prometheus/index.js

@@ -1,8 +1,12 @@
 'use strict';
 
+const { DiagConsoleLogger, DiagLogLevel, diag } = require('@opentelemetry/api');
 const { MeterProvider } = require('@opentelemetry/sdk-metrics-base');
 const { PrometheusExporter } = require('@opentelemetry/exporter-prometheus');
 
+// Optional and only needed to see the internal diagnostic logging (during development)
+diag.setLogger(new DiagConsoleLogger(), DiagLogLevel.DEBUG);
+
 const { endpoint, port } = PrometheusExporter.DEFAULT_OPTIONS;
 
 const exporter = new PrometheusExporter({}, () => {
@@ -11,11 +15,12 @@ const exporter = new PrometheusExporter({}, () => {
   );
 });
 
-const meter = new MeterProvider({
-  exporter,
-  interval: 1000,
-}).getMeter('example-prometheus');
+// Creates MeterProvider and installs the exporter as a MetricReader
+const meterProvider = new MeterProvider();
+meterProvider.addMetricReader(exporter);
+const meter = meterProvider.getMeter('example-prometheus');
 
+// Creates metric instruments
 const requestCounter = meter.createCounter('requests', {
   description: 'Example of a Counter',
 });
@@ -26,6 +31,7 @@ const upDownCounter = meter.createUpDownCounter('test_up_down_counter', {
 
 const labels = { pid: process.pid, environment: 'staging' };
 
+// Record metrics
 setInterval(() => {
   requestCounter.add(1, labels);
   upDownCounter.add(Math.random() > 0.5 ? 1 : -1, labels);

examples/prometheus/package.json → experimental/examples/prometheus/package.json

@@ -1,6 +1,6 @@
 {
   "name": "prometheus-example",
-  "version": "0.25.0",
+  "version": "0.28.0",
   "description": "Example of using @opentelemetry/sdk-metrics-base and  @opentelemetry/exporter-prometheus",
   "main": "index.js",
   "scripts": {
@@ -10,7 +10,7 @@
   "license": "Apache-2.0",
   "dependencies": {
     "@opentelemetry/api": "^1.0.2",
-    "@opentelemetry/exporter-prometheus": "0.25.0",
-    "@opentelemetry/sdk-metrics-base": "0.25.0"
+    "@opentelemetry/exporter-prometheus": "0.28.0",
+    "@opentelemetry/sdk-metrics-base": "0.28.0"
   }
 }

examples/prometheus/prometheus.yml → experimental/examples/prometheus/prometheus.yml

@@ -6,4 +6,4 @@ scrape_configs:
     # metrics_path defaults to '/metrics'
     # scheme defaults to 'http'.
     static_configs:
-    - targets: ['localhost:9464']
+    - targets: ['172.16.123.1:9464']