Replace Console with bunyan logger in Sample App (#186)

*Description of changes:*
There are currently no OTel supported logs being emitted from the
sample-app.

Replaces sample-app logging with `bunyan` in order for OpenTelemetry to
auto-instrument the logging library from the app.

/aws-sdk-s3:
```
{"name":"express-app","hostname":"ip-172-31-7-29.us-west-2.compute.internal","pid":2522078,"level":30,"msg":"done aws sdk s3 request","time":"2025-05-28T17:52:53.115Z","v":0}
{"name":"express-app","hostname":"ip-172-31-7-29.us-west-2.compute.internal","pid":2522078,"level":50,"msg":"Exception thrown: Invalid value \"undefined\" for header \"X-Amzn-Trace-Id\"","time":"2025-05-28T17:52:54.132Z","v":0}
```

/http:
```
{"name":"express-app","hostname":"ip-172-31-7-29.us-west-2.compute.internal","pid":2522078,"level":30,"msg":"random value from http request: [94]\n","time":"2025-05-28T17:54:09.786Z","v":0}
```
/rolldice:
```
{"name":"express-app","hostname":"ip-172-31-7-29.us-west-2.compute.internal","pid":2522987,"level":30,"msg":"rolldice: 1","time":"2025-05-28T17:54:52.830Z","v":0}
```

By submitting this pull request, I confirm that you can use, modify,
copy, and redistribute this contribution, under the terms of your
choice.

Author: liustve

sample-applications/simple-express-server/sample-app-express-server.js

@@ -2,19 +2,27 @@
 
 const http = require('http');
 const express = require('express');
+const bunyan = require('bunyan');
 const { S3Client, ListObjectsCommand } = require('@aws-sdk/client-s3');
 
 const PORT = parseInt(process.env.SAMPLE_APP_PORT || '8080', 10);
 
 const app = express();
 
+// Uses bunyan logger
+const logger = bunyan.createLogger({name: 'express-app', level: 'info'});
+
 async function getRandomNumber(min, max) {
   return Math.floor(Math.random() * (max - min) + min);
 }
 
+// Generate logs in your endpoints
 app.get('/rolldice', (req, res) => {
+
   getRandomNumber(1, 6).then((val) => {
-    res.send(`rolldice: ${val.toString()}`);
+    const msg = `rolldice: ${val.toString()}`
+    logger.info(msg);
+    res.send(msg);
   });
 });
 
@@ -29,7 +37,9 @@ app.get('/http', (req, res) => {
   const httpRequest = http.request(options, (rs) => {
     rs.setEncoding('utf8');
     rs.on('data', (result) => {
-      res.send(`random value from http request: ${result}`);
+      const msg = `random value from http request: ${result}`
+      logger.info(msg);
+      res.send(msg);
     });
     rs.on('error', console.log);
   });
@@ -45,14 +55,16 @@ app.get('/aws-sdk-s3', async (req, res) => {
         Bucket: bucketName,
       }),
     ).then((data) => {
-      console.log(data);
+      logger.info(data);
     });
   } catch (e) {
     if (e instanceof Error) {
-      console.error('Exception thrown: ', e.message);
+      logger.error(`Exception thrown: ${e.message}`);
     }
   } finally {
-    res.send('done aws sdk s3 request');
+    const msg = 'done aws sdk s3 request'
+    logger.info(msg);
+    res.send(msg);
   }
 });