How to Use Git from Shell for Your GitLab Coding Projects

GitLab is a versatile platform for collaborative Git repositories, supporting open-source and private development projects. With robust features like issue tracking, wikis, and CI/CD pipelines, GitLab empowers teams to collaborate effectively and deliver exceptional software solutions.

In this advanced tutorial, we will guide you through creating a GitLab account, setting up a Node.js project using Express Generator, pushing your project to GitLab, and automating deployment using Git from the terminal along with GitLab's CI/CD pipelines. Each step includes practical examples and clear explanations to ensure comprehensive understanding and useful application.

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Creating a GitLab Account

1. Verify Your Email Address: Complete the registration on GitLab.com and activate your account by clicking the confirmation link sent to your email.

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Setting up the Node.js Project

2. Install and Use Express Generator: Express Generator is a tool that simplifies the creation of Node.js applications using the Express framework. Install it globally to use it for creating a new project:

    $ npm install -g express-generator
   

   This command installs Express Generator globally on your system.

3. Create a New Node.js Project: Generate a new project named my-node-app using Express Generator. This command will create a structured project directory with essential files and directories for an Express application:

    $ express my-node-app
   

   After running this command, you will see the following directory structure created for your project:

    my-node-app/
    ├── bin/
    │   └── www
    ├── public/
    │   ├── images/
    │   ├── javascripts/
    │   └── stylesheets/
    │       └── style.css
    ├── routes/
    │   ├── index.js
    │   └── users.js
    ├── views/
    │   ├── error.jade
    │   ├── index.jade
    │   └── layout.jade
    ├── app.js
    └── package.json
   

   Note: Depending on the version of Express Generator, the view files may use .pug instead of .jade.

4. Navigate to the Project Directory: Change into the newly created project directory:

    $ cd my-node-app
   

   Now, you're ready to start working on your Node.js project.

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Initializing and Using Git

5. Initialize Git: Start version control for your project by initializing a new Git repository:

    bashCopy code$ git init
   

   This command initializes a new Git repository in your project directory, creating a .git folder to manage versioning.

6. Add and Commit Changes: Add all files in the project directory to the Git staging area and commit them with a meaningful message:

    bashCopy code$ git add .
    $ git commit -m "Initial commit"
   

   This records the initial state of your project in Git.

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Creating and Using a GitLab Repository

7. Create a GitLab Repository:

   • Log in to GitLab.com, navigate to your dashboard, and click on the plus icon to create a new project (demo-repository). Choose the visibility level (public or private) and create the repository.

8. Add GitLab Repository as Remote:

   • Link your local Git repository to the newly created GitLab repository by adding it as the remote origin:

       $ git remote add origin https://gitlab.com/your-username/demo-repository.git
     

     Replace your-username with your actual GitLab username.

9. Push Changes to GitLab:

   • Push your committed changes from the local repository to GitLab:

       $ git push -u origin main
     

     This command uploads your project files to GitLab under the main branch.

     Troubleshooting Tip: If you encounter authentication errors during the push, ensure your GitLab credentials are correctly configured. You might need to update your Git global configuration with your GitLab username and email:

       bashCopy code$ git config --global user.name "Your Name"
       $ git config --global user.email "your.email@example.com"
     

     Verify your configuration with:

       $ git config --global --list
     

     If necessary, update the remote URL for the origin:

       $ git remote set-url origin https://gitlab.com/your-username/demo-repository.git
     

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Advanced Topics: Implementing Continuous Integration and Deployment (CI/CD)

10. Configure CI/CD Pipeline:

    • Create a .gitlab-ci.yml file in the root directory of your project to define the CI/CD pipeline stages and jobs:

        stages:
          - build
          - test
          - deploy
      
        build:
          stage: build
          script:
            - npm install
          only:
            - main
      
        test:
          stage: test
          script:
            - npm test
          only:
            - main
      
        deploy:
          stage: deploy
          script:
            - echo "Deploying to production server"
            # Add deployment commands here
          only:
            - main
      

      This configuration file sets up stages for building, testing, and deploying your application, ensuring automated workflows.

      Troubleshooting Tip: If the CI/CD pipeline fails, review the pipeline logs on GitLab to identify errors in the build, test, or deployment stages. Common issues include missing dependencies, configuration errors, or access permissions.

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Monitoring and Advanced GitLab Features

11. Monitor CI/CD Pipeline:

    • Track the progress and status of your CI/CD pipeline on GitLab to ensure the successful execution of the build, test, and deployment stages.

12. Collaboration and Code Review:

    • Leverage GitLab's merge requests, code reviews, and inline commenting features to collaborate effectively with team members, ensuring code quality and adherence to project standards.

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Complete Node.js Project Code (app.js)

Here's the complete code for app.js, the main entry point of your Node.js application created with Express Generator:

const express = require('express');
const path = require('path');
const cookieParser = require('cookie-parser');
const logger = require('morgan');

const indexRouter = require('./routes/index');
const usersRouter = require('./routes/users');

const app = express();

// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');

app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));

app.use('/', indexRouter);
app.use('/users', usersRouter);

// catch 404 and forward to error handler
app.use(function(req, res, next) {
  next(createError(404));
});

// error handler
app.use(function(err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

  // render the error page
  res.status(err.status || 500);
  res.render('error');
});

module.exports = app;

This app.js file sets up a basic Express application with middleware like morgan for logging, cookie-parser for parsing cookies, and express.static for serving static files. It also includes routes defined in index.js and users.js.

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Conclusion

Congratulations! You've successfully set up a GitLab account, created a Node.js project using Express Generator, integrated Git for version control, automated deployment with GitLab's CI/CD pipelines, and explored advanced GitLab features for collaboration and monitoring. Apply these practices to streamline your development workflows and confidently deliver high-quality software projects using GitLab.