feat(#60): dashboards with CHT api express metrics

development/fake-cht/package.json

@@ -4,6 +4,9 @@
   "scripts": {
     "start": "node src/index.js"
   },
+  "engines" : { 
+    "node" : ">=18.0.0"
+  },
   "dependencies": {
     "express": "^4.18.2",
     "pg": "^8.10.0",

development/fake-cht/src/index.js

@@ -116,9 +116,40 @@ try {
 app.use(prometheusMiddleware({
   metricsPath: '/api/v1/express-metrics',
   metricsPrefix: 'cht_api',
+  // based on one-month analysed period of production traffic
+  durationBuckets: [
+    0.004, 0.007, 0.013, 0.025, 0.05,
+    0.1, 0.25, 0.5, 1, 2,
+    3, 5, 7.5, 10, 25,
+    45, 90, 180, 360, 600,
+    1200, 1800, 3600
+  ],
 }));
 
+const replicationRoutes = [
+  '/api/v1/replication/get-ids',
+  '/api/v1/initial-replication/get-ids'
+];
+
+app.get(replicationRoutes, (req, res) => {
+  const timeout = getRandomInt(0, 5000);
+  setTimeout(() => {
+    if (timeout > 4000) {
+      res
+        .status(504)
+        .send({ message: 'Timeout' });
+      return;
+    }
+    res.json({ id: new Date().getTime() });
+  }, timeout);
+});
+
 app.get('/api/v2/monitoring', (req, res) => {
+  // generate requests to other endpoints
+  replicationRoutes.forEach(replicationRoute => {
+    fetch(`http://fake-cht:8081${replicationRoute}`);
+  });
+
   const metrics = {
     version: getVersion(),
     couchdb: getAllCouchDbs(lastResponse.couchdb),