add docker nodejs express app

Author: yiyuan-he

samples/cloudwatch-applicationsignals-mcp/get-enablement-guide-samples/README.md

@@ -48,9 +48,10 @@ docker buildx build --platform linux/amd64,linux/arm64 \
   .
 ```
 
-| Language-Framework | App Directory            | ECR Repo     |
-|--------------------|--------------------------|--------------|
-| python-flask       | docker-apps/python/flask | python-flask |
+| Language-Framework | App Directory              | ECR Repo       |
+|--------------------|----------------------------|----------------|
+| python-flask       | docker-apps/python/flask   | python-flask   |
+| nodejs-express     | docker-apps/nodejs/express | nodejs-express |
 
 ##### Deploy & Cleanup Containerized Infrastructure
 
@@ -67,6 +68,7 @@ cdk deploy <stack-name>
 cdk destroy <stack-name>
 ```
 
-| Language-Framework | Stack Name          |
-|--------------------|---------------------|
-| python-flask       | PythonFlaskCdkStack |
+| Language-Framework | Stack Name            |
+|--------------------|---------------------- |
+| python-flask       | PythonFlaskCdkStack   |
+| nodejs-express     | NodejsExpressCdkStack |

samples/cloudwatch-applicationsignals-mcp/get-enablement-guide-samples/docker-apps/nodejs/express/Dockerfile

@@ -0,0 +1,50 @@
+# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Use the official Node.js image as the base
+FROM node:20-alpine
+
+# Install curl
+RUN apk add --no-cache curl
+
+# Set working directory
+WORKDIR /app
+
+# Copy package files first for better layer caching
+COPY package*.json ./
+
+# Install dependencies
+RUN npm ci --only=production
+
+# Copy app to image
+COPY . ./
+
+# Set environment variables
+ENV NODE_ENV=production
+ENV HOST=0.0.0.0
+ENV PORT=8080
+
+# Change ownership to the built-in node user
+RUN chown -R node:node /app
+
+USER node
+
+# Expose the port that the app will run on
+EXPOSE 8080
+
+HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
+    CMD curl -f http://localhost:8080/health || exit 1
+
+# Command to start the application
+CMD ["npm", "run", "start"]

samples/cloudwatch-applicationsignals-mcp/get-enablement-guide-samples/docker-apps/nodejs/express/app.js

@@ -0,0 +1,62 @@
+// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+'use strict';
+
+const express = require('express');;
+const { S3Client, ListBucketsCommand } = require('@aws-sdk/client-s3');
+const logger = require('pino')()
+
+const HOST = process.env.HOST || '0.0.0.0';
+const PORT = parseInt(process.env.PORT || '8080', 10);
+
+const app = express();
+
+const s3Client = new S3Client({ region: 'us-east-1' });
+
+app.get('/', (req, res) => {
+  healthCheck(res);
+});
+
+app.get('/health', (req, res) => {
+  healthCheck(res);
+});
+
+function healthCheck(res) {
+  logger.info('Health check endpoint called');
+  res.type('application/json').send(JSON.stringify({status: 'healthy'}) + '\n');
+}
+
+app.get('/api/buckets', async (req, res) => {
+  try {
+    const data = await s3Client.send(new ListBucketsCommand({}));
+    const buckets = data.Buckets.map(bucket => bucket.Name);
+    logger.info(`Successfully listed ${buckets.length} S3 buckets`);
+    res.type('application/json').send(JSON.stringify({
+      bucket_count: buckets.length,
+      buckets: buckets
+    }) + '\n');
+  } catch (e) {
+    if (e instanceof Error) {
+      logger.error(`Exception thrown when Listing Buckets: ${e.message}`);
+    }
+    res.status(500).type('application/json').send(JSON.stringify({
+      error: 'Failed to retrieve S3 buckets'
+    }) + '\n');
+  }
+});
+
+app.listen(PORT, HOST, () => {
+  logger.info(`Listening for requests on ${HOST}:${PORT}`);
+});

samples/cloudwatch-applicationsignals-mcp/get-enablement-guide-samples/docker-apps/nodejs/express/generate-traffic.sh

@@ -0,0 +1,39 @@
+#!/bin/bash
+# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Traffic generator script for Express application
+PORT=${PORT:-8080}
+BASE_URL="http://localhost:${PORT}"
+
+echo "Starting continuous traffic generation to ${BASE_URL}"
+
+while true; do
+    echo "[$(date '+%H:%M:%S')] Generating traffic..."
+
+    # Health check
+    curl -sf "${BASE_URL}/health" > /dev/null
+    if [ $? -ne 0 ]; then
+        echo "[$(date '+%H:%M:%S')] ERROR: Health check failed!"
+    fi
+
+    # API call (S3 buckets)
+    curl -sf "${BASE_URL}/api/buckets" > /dev/null
+    if [ $? -ne 0 ]; then
+        echo "[$(date '+%H:%M:%S')] ERROR: API call to /api/buckets failed!"
+    fi
+
+    # Sleep between requests
+    sleep 2
+done