Deploy a Spring Boot application to Cloud Foundry with GitLab CI/CD

Introduction

In this article, we'll demonstrate how to deploy a Spring Boot application to Cloud Foundry (CF) with GitLab CI/CD using the Continuous Deployment method.

All the code for this project can be found in this GitLab repo.

In case you're interested in deploying Spring Boot applications to Kubernetes using GitLab CI/CD, read through the blog post Continuous Delivery of a Spring Boot application with GitLab CI and Kubernetes.

Requirements

This tutorial assumes you are familiar with Java, GitLab, Cloud Foundry, and GitLab CI/CD.

To follow along, you will need:

An account on Pivotal Web Services (PWS) or any other Cloud Foundry (CF) instance.
An account on GitLab.

NOTE: Note: You will need to replace the api.run.pivotal.io URL in the all below commands with the API URL of your CF instance if you're not deploying to PWS.

Create your project

To create your Spring Boot application you can use the Spring template in GitLab when creating a new project:

Configure the deployment to Cloud Foundry

To deploy to Cloud Foundry we need to add a manifest.yml file. This is the configuration for the CF CLI we will use to deploy the application. We will create this in the root directory of our project with the following content:

---
applications:
- name: gitlab-hello-world
  random-route: true
  memory: 1G
  path: target/demo-0.0.1-SNAPSHOT.jar

Configure GitLab CI/CD to deploy your application

Now we need to add the GitLab CI/CD configuration file (.gitlab-ci.yml) to our project's root. This is how GitLab figures out what commands need to be run whenever code is pushed to our repository. We will add the following .gitlab-ci.yml file to the root directory of the repository, GitLab will detect it automatically and run the steps defined once we push our code:

image: java:8

stages:
  - build
  - deploy

before_script:
  - chmod +x mvnw

build:
  stage: build
  script: ./mvnw package
  artifacts:
    paths:
      - target/demo-0.0.1-SNAPSHOT.jar

production:
  stage: deploy
  script:
  - curl --location "https://cli.run.pivotal.io/stable?release=linux64-binary&source=github" | tar zx
  - ./cf login -u $CF_USERNAME -p $CF_PASSWORD -a api.run.pivotal.io
  - ./cf push
  only:
  - master

We've used the java:8 docker image to build our application as it provides the up-to-date Java 8 JDK on Docker Hub. We've also added the only clause to ensure our deployments only happen when we push to the master branch.

Now, since the steps defined in .gitlab-ci.yml require credentials to login to CF, you'll need to add your CF credentials as environment variables on GitLab CI/CD. To set the environment variables, navigate to your project's Settings > CI/CD and expand Variables. Name the variables CF_USERNAME and CF_PASSWORD and set them to the correct values.

Once set up, GitLab CI/CD will deploy your app to CF at every push to your repository's default branch. To see the build logs or watch your builds running live, navigate to CI/CD > Pipelines.

CAUTION: Caution: It is considered best practice for security to create a separate deploy user for your application and add its credentials to GitLab instead of using a developer's credentials.

To start a manual deployment in GitLab go to CI/CD > Pipelines then click on Run Pipeline. Once the app is finished deploying it will display the URL of your application in the logs for the production job like:

requested state: started
instances: 1/1
usage: 1G x 1 instances
urls: gitlab-hello-world-undissembling-hotchpot.cfapps.io
last uploaded: Mon Nov 6 10:02:25 UTC 2017
stack: cflinuxfs2
buildpack: client-certificate-mapper=1.2.0_RELEASE container-security-provider=1.8.0_RELEASE java-buildpack=v4.5-offline-https://github.com/cloudfoundry/java-buildpack.git#ffeefb9 java-main java-opts jvmkill-agent=1.10.0_RELEASE open-jdk-like-jre=1.8.0_1...

     state     since                    cpu      memory         disk           details
#0   running   2017-11-06 09:03:22 PM   120.4%   291.9M of 1G   137.6M of 1G

You can then visit your deployed application (for this example, https://gitlab-hello-world-undissembling-hotchpot.cfapps.io/) and you should see the "Spring is here!" message.