How to Implement CICD Pipeline using GitLab Yaml | GitLab CICD Tutorials | GitLab CICD Pipeline | Build Java WAR file using GitLab CICD YAML file

Here below is the code for creating GitLab CICD yaml file for Java Web App project to automate build and deployment. 

What is GitLab CICD?

GitLab CI/CD is a continuous integration and continuous deployment solution built into GitLab.

GitLab CI/CD

GitLab CI/CD is a feature of GitLab that automates:

• Building code
• Testing applications
• Scanning code
• Deploying applications

whenever developers push code into Git repositories.

What is .gitlab-ci.yml?

The .gitlab-ci.yml file is the heart of GitLab CI/CD pipelines.

It contains:

• Pipeline stages
• Jobs
• Scripts
• Variables
• Artifacts
• Deployment instructions

GitLab automatically reads this file whenever code changes are pushed into the repository. GitLab Runner uses a Docker container image to run the job. 

.gitlab-ci.yml for implementing CICD using GitLab

stages:

  - build

  - deploy

build_war:

  stage: build

  image: maven:3.8.6-eclipse-temurin-11

  script:

    - echo "Building WAR file using Maven"

    - mvn clean install -f MyWebApp/pom.xml

    - echo "Listing target directory"

    - ls -la MyWebApp/target

  artifacts:

    paths:

      - MyWebApp/target/*.war

    expire_in: 1 hour

deploy_to_tomcat:

  stage: deploy

  image: curlimages/curl:latest

  dependencies:

    - build_war

  script:

    - echo "Deploying WAR file to Tomcat running on AWS EC2"

    - |

      curl -v -u ${TOMCAT_USER}:${TOMCAT_PASSWORD} \

      -T MyWebApp/target/MyWebApp.war \

      "http://${TOMCAT_HOST}/manager/text/deploy?path=/MyWebApp&update=true"