> ## Documentation Index > Fetch the complete documentation index at: https://notes.kodekloud.com/llms.txt > Use this file to discover all available pages before exploring further. # Run and Test NodeJS App on Local Machine > Learn to run and test the Solar System Node.js application locally before integrating it into a GitLab CI/CD pipeline. Learn how to run and test the Solar System Node.js application locally before integrating it into a GitLab CI/CD pipeline. The source code is hosted on GitLab. ![The image shows a GitLab repository page for a project named "Solar-System," displaying the project files and their last commit details. The interface includes options for managing, planning, and deploying the project.](https://kodekloud.com/kk-media/image/upload/v1752877290/notes-assets/images/GitLab-CICD-Architecting-Deploying-and-Optimizing-Pipelines-Run-and-Test-NodeJS-App-on-Local-Machine/gitlab-solar-system-repo-page.jpg) ## Prerequisites * Node.js and npm * A running MongoDB instance or Atlas cluster * Git installed on your machine To verify Node.js and npm: ```bash theme={null} node --version # e.g., v18.x.x npm --version # e.g., 9.x.x ``` ## Clone the Repository ```bash theme={null} git clone https://gitlab.com/sidd-harth/solar-system.git cd solar-system ``` ## Project Structure and Key Files This repository includes: * **package.json**: Defines metadata, scripts, dependencies, and coverage thresholds * **app.js**: Backend Express.js server * **client.js**: Frontend script to fetch planet data * **Dockerfile**: Build instructions for a Docker image * **deployment.yaml** & **service.yaml**: Kubernetes manifests ### package.json ```json theme={null} { "name": "Solar System", "version": "6.7.6", "author": "Siddharth Barahalikar", "license": "MIT", "scripts": { "start": "node app.js", "test": "mocha app-test.js --timeout 10000 --reporter mocha-junit-reporter --exit", "coverage": "nyc --reporter cobertura --reporter lcov --reporter text --reporter json-summary mocha app-test.js" }, "nyc": { "check-coverage": true, "lines": 90 }, ... } ``` | Script | Description | Command | | -------- | ------------------------------------------- | ------------------ | | start | Launch the Express server | `npm start` | | test | Run tests with Mocha and JUnit reporter | `npm test` | | coverage | Generate coverage reports (cobertura, lcov) | `npm run coverage` | ### Application Backend (app.js) ```javascript theme={null} const path = require('path'); const express = require('express'); const bodyParser = require('body-parser'); const cors = require('cors'); const mongoose = require('mongoose'); const app = express(); app.use(bodyParser.json()); app.use(express.static(path.join(__dirname, '/'))); app.use(cors()); mongoose.connect(process.env.MONGO_URI, { user: process.env.MONGO_USERNAME, pass: process.env.MONGO_PASSWORD, useNewUrlParser: true, useUnifiedTopology: true }, (err) => { if (err) { console.error("Connection error:", err); } else { console.log("Connected to MongoDB"); } }); app.listen(3000, () => { console.log("Server running on port 3000"); }); ``` Ensure you add your REST API route handlers in `app.js` (for example, a GET `/os` endpoint) before testing. ### Frontend Controller (client.js) ```javascript theme={null} console.log('Client script loaded'); window.onload = () => { console.log("Requesting all planets"); fetch("/os", { method: "GET" }) .then(res => res.ok ? res.json() : Promise.reject("Fetch error")) .then(data => console.log(data)) .catch(error => console.error(error)); }; ``` ### Dockerfile ```dockerfile theme={null} FROM node:18-alpine3.17 WORKDIR /usr/app COPY package*.json ./ RUN npm install COPY . . ENV MONGO_URI=uriPlaceholder ENV MONGO_USERNAME=usernamePlaceholder ENV MONGO_PASSWORD=passwordPlaceholder EXPOSE 3000 CMD ["npm", "start"] ``` ### Kubernetes Manifests ```yaml theme={null} # deployment.yaml apiVersion: apps/v1 kind: Deployment metadata: name: solar-system labels: app: solar-system spec: replicas: 2 selector: matchLabels: app: solar-system template: metadata: labels: app: solar-system spec: containers: - name: solar-system image: your-repo/solar-system:latest ports: - containerPort: 3000 --- # service.yaml apiVersion: v1 kind: Service metadata: name: solar-system labels: app: solar-system spec: type: NodePort selector: app: solar-system ports: - port: 3000 targetPort: 3000 protocol: TCP ``` | Resource Type | Purpose | Example | | ------------- | -------------------------------- | ---------------------------- | | Deployment | Manages pods and rolling updates | Defined in `deployment.yaml` | | Service | Exposes pods on the network | Defined in `service.yaml` | ## Install Dependencies ```bash theme={null} npm install ``` You may see notices: ```plaintext theme={null} 44 packages are looking for funding Run `npm fund` for details 1 high severity vulnerability To address all issues, run: npm audit fix ``` ## Running the Server Locally After dependencies are installed: ```bash theme={null} npm start ``` Open [http://localhost:3000](http://localhost:3000) in your browser: ![The image shows a digital illustration of the solar system with planets orbiting the sun, accompanied by a user interface for searching planets. The background is a starry space theme with text describing the solar system.](https://kodekloud.com/kk-media/image/upload/v1752877291/notes-assets/images/GitLab-CICD-Architecting-Deploying-and-Optimizing-Pipelines-Run-and-Test-NodeJS-App-on-Local-Machine/solar-system-planets-ui-illustration.jpg) You can search by ID (e.g., 3 for Earth, 6 for Saturn). Data is fetched from your MongoDB. ![The image shows a webpage about the solar system, specifically focusing on Saturn, with a stylized illustration of the planet and its rings on a starry background. There is a description of Saturn and a search feature for exploring planets.](https://kodekloud.com/kk-media/image/upload/v1752877292/notes-assets/images/GitLab-CICD-Architecting-Deploying-and-Optimizing-Pipelines-Run-and-Test-NodeJS-App-on-Local-Machine/saturn-solar-system-webpage-illustration.jpg) ## Testing the Application Run the test suite: ```bash theme={null} npm test ``` If environment variables are missing, you will see: ```plaintext theme={null} MongooseError: The `uri` parameter to `openUri()` must be a string, got `undefined`. ``` Tests will fail without `MONGO_URI`, `MONGO_USERNAME`, and `MONGO_PASSWORD`. Set these before running `npm test`. ### Temporary Local Credentials For a quick local demo, hard-code your MongoDB URI in `app.js`: ```javascript theme={null} mongoose.connect('mongodb+srv://supercluster.d83jj.mongodb.net/superData', { user: 'superuser', pass: 'SuperPassword', useNewUrlParser: true, useUnifiedTopology: true }, (err) => { if (err) console.error("Connection error:", err); }); ``` Re-run tests: ```bash theme={null} npm test echo $? # 0 means success ``` A `test_results.xml` file is generated for CI/CD: ```xml theme={null} ``` ## Coverage Report Generate coverage: ```bash theme={null} npm run coverage ``` ```plaintext theme={null} 11 passing (4s) ERROR: Coverage for lines (88.88%) does not meet global threshold (90%) ``` A non-zero exit code will signal coverage failures in CI pipelines. ## Links and References * [Node.js](https://nodejs.org/) * [npm](https://www.npmjs.com/) * [Express Documentation](https://expressjs.com/) * [Mongoose Documentation](https://mongoosejs.com/) * [Mocha](https://mochajs.org/) * [nyc (Istanbul)](https://github.com/istanbuljs/nyc) * [Docker Hub](https://hub.docker.com/) * [Kubernetes Basics](https://kubernetes.io/docs/concepts/overview/what-is-kubernetes/)