This repository contains PoCs for various experimental DevOps approaches when harnessing GitLab to perform deployment of dockerized applications to the Cloud

In particular, the idea of dynamically generated CI/CD pipeline is investigated (ie. gitlab-ci.yml file or its parts are generated in runtime)

• gcloud (with non-null value of env var GOOGLE_APPLICATION_CREDENTIALS)
• npm
• python3.8
• account at GitLab

To demonstrate how to work with containerized apps, we are going to use a simple node.js app

cd ./app
npm install
node index.js

Go to localhost:8080 and observe "Hello, World!" simple web page

sudo docker build -t nodejs-demo:1.0.0 .
sudo docker images
sudo docker run -ti --name nodejs-app -p 8080:8080 -d nodejs-demo:1.0.0

(In case of "container already running error", stop that container with command sudo docker rm <container_id>)

The last command will run the container with app in a daemon mode; it can also be visible using the docker command:

sudo docker ps

CONTAINER ID   IMAGE         COMMAND                  CREATED          STATUS          PORTS                                       NAMES
6aadf0b63d2f   nodejs-demo   "docker-entrypoint.s…"   24 seconds ago   Up 23 seconds   0.0.0.0:8080->8080/tcp, :::8080->8080/tcp   nodejs-app

To stop container, type the command:

sudo docker stop 6aadf0b63d2f

After successful testing tag and publish docker to GCR:

GOOGLE_CLOUD_PROJECT=gcp-tooling-api
gcloud config set project gcp-tooling-api
gcloud services enable containerregistry.googleapis.com 
sudo docker tag nodejs-demo:1.0.0 eu.gcr.io/$GOOGLE_CLOUD_PROJECT/nodejs-demo:v1
sudo docker push eu.gcr.io/$GOOGLE_CLOUD_PROJECT/nodejs-demo:v1

To create GCP infrastructure with aforementioned simple app, use the script gcp/create_insfrastructure.sh

This script will do the following:

• create template for instance in instance group
• create managed instance group itself
• create and attach auto-scaling policy to instance group

First for convinience create env variables GITLAB_USERNAME, GITLAB_PASSWORD to hold GitLab's docker registry creds (note, this is not the secure place to hold secrets and consider using providers); set docker registry url via export GITLAB_DOCKER_REGISTRY=registry.gitlab.com:

sudo nano ~/.profile
source ~/.profile

The following commands build and push image for GitLab runners

cd ./docker
export GROUP=<name of the group>
./build_image.sh

Note the image URL - it can be used now for GitLab Runners.

Create a GitLab trigger token (Settings -> CI/CD -> Pipeline triggers) and put it into GITLAB_TOKEN env variable. Create a GitLab access token (PAT, User Settings -> Access Tokens) and put it into PAT_TOKEN env variable. Create a RUNNER_CUSTOM_IMAGE env variable in CI/CD area:

curl --request POST --header "PRIVATE-TOKEN: $PAT_TOKEN" \
     "https://gitlab.com/api/v4/projects/41024544/variables" \
     --form "key=RUNNER_CUSTOM_IMAGE" \
     --form "value=registry.gitlab.com/automation299/gitlab-automation:a9316a0"