Node express

.gitignore

@@ -5,7 +5,6 @@
 /React-Todo-list-main/.pnp
 /React-Todo-list-main/package-lock.json
 
-
 # testing
 /coverage
 
@@ -22,3 +21,8 @@
 npm-debug.log*
 yarn-debug.log*
 yarn-error.log*
+
+# express app
+node-express/.env
+node-express/node_modules
+

node-express/app.js

@@ -0,0 +1,56 @@
+require('dotenv').config();
+const statsig = require('statsig-node');
+const express = require('express');
+const { v4: uuidv4 } = require('uuid');
+const { engine } = require('express-handlebars');
+const cookieParser = require('cookie-parser');
+const app = express();
+const port = 3000;
+
+app.use(cookieParser());
+app.engine('.hbs', engine({ extname: '.hbs' }));
+app.set('view engine', '.hbs');
+app.set('views', './views');
+
+/**
+* global middleware to set a cookie if it doesn't exist
+* passes the uuid down to route handlers on req object
+*/
+app.use(async (req, res, next) => {
+  let statsigDeviceID;
+  if (req.cookies['statsig_uuid']) {
+    statsigDeviceID = req.cookies['statsig_uuid'];
+  }
+  else {
+    statsigDeviceID = uuidv4();
+    res.cookie('statsig_uuid', statsigDeviceID);
+  }
+  req.statsigDeviceID = statsigDeviceID;
+  next();
+})
+
+app.get('/', async (req, res) => {
+  const user = {
+    // use the random uuid in cookie as the userID
+    // in practice, you'd use a known userID here
+    userID: req.statsigDeviceID,
+    country: 'US',
+    custom: {
+      employee: true
+    }
+  };
+  const testGroup = statsig.getExperimentSync(user, 'express_app_test').get('variant', 'control');
+  const backgroundFeatureEnabled = statsig.checkGate(user, 'express_app_bg');
+  res.render('index.hbs', { 
+    testGroup,
+    backgroundFeatureEnabled
+  });
+});
+
+app.listen(port, async () => {
+  const runtimeEnv = process.env.STATSIG_ENV_TIER || 'production';
+  await statsig.initialize(process.env.STATSIG_SERVER_KEY, {
+    environment: { tier: runtimeEnv },
+  });
+  console.log(`Example app listening in ${runtimeEnv} on port ${port}`);
+})