This is a Python Flask web application that demonstrates GitLab CI/CD pipeline implementation with AWS CloudFormation deployment. The app provides system information and real-time monitoring screen with dials showing CPU, memory, IO and process information.
The app has been designed with cloud native demos & containers in mind, in order to provide a real working application for deployment, something more than "hello-world" but with the minimum of pre-reqs. It is not intended as a complete example of a fully functioning architecture or complex software design.
Typical uses would be deployment to Kubernetes, demos of Docker, GitLab CI/CD (build pipelines are provided), deployment to cloud (AWS) monitoring, auto-scaling
- Be using Linux, WSL or MacOS, with bash, make etc
- Python 3.8+ - for running locally, linting, running tests etc
- Docker - for running as a container, or image build and push
- AWS CLI - for deployment to AWS
- GitLab account - for CI/CD pipeline execution
Clone the project to any directory where you do development work
git clone https://github.com/tkoppine/Flask-Monitor-GitLab-CI-CD-Demo.git
A standard GNU Make file is provided to help with running and building locally.
help 💬 This help message
lint 🔎 Lint & format, will not fix but sets exit code on error
lint-fix 📜 Lint & format, will try to fix errors and modify code
image 🔨 Build container image from Dockerfile
push 📤 Push container image to registry
run 🏃 Run the server locally using Python & Flask
deploy 🚀 Deploy to AWS using CloudFormation
test 🎯 Unit tests for Flask app
test-report 🎯 Unit tests for Flask app (with report output)
test-api 🚦 Run integration API tests, server must be running
clean 🧹 Clean up project
Make file variables and default values, pass these in when calling make, e.g. make image IMAGE_REPO=your-repo/app-name
| Makefile Variable | Default | Description |
|---|---|---|
| IMAGE_REG | docker.io | Container registry URL |
| IMAGE_REPO | ${DOCKER_USERNAME}/flask-app | Docker repository name |
| IMAGE_TAG | latest | Container image tag |
| AWS_REGION | us-east-2 | AWS deployment region |
| STACK_NAME | FlaskAppStack | CloudFormation stack name |
The app runs under Flask and listens on port 5000 by default, this can be changed with the PORT environmental variable.
Container images can be built and pushed to your preferred registry.
Run in a container with:
docker run --rm -it -p 5000:5000 ${IMAGE_REG}/${IMAGE_REPO}:${IMAGE_TAG}Should you want to build your own container, use make image and the above variables to customise the name & tag.
The app can easily be deployed to Kubernetes using Helm, see deploy/kubernetes/readme.md for details
A working GitLab CI/CD pipeline is provided in .gitlab-ci.yml, automated builds and deployments are run in GitLab hosted runners.
The pipeline includes the following stages:
- Test (commented): Run unit tests
- Build (commented): Build and push Docker image
- Deploy: Deploy to AWS using CloudFormation
Configure these variables in your GitLab project settings (Settings > CI/CD > Variables):
| Variable Name | Description | Required |
|---|---|---|
REGISTRY_USER |
Docker registry username | Yes |
REGISTRY_PASS |
Docker registry password | Yes |
AWS_ACCESS_KEY_ID |
AWS access key | Yes |
AWS_SECRET_ACCESS_KEY |
AWS secret key | Yes |
AWS_DEFAULT_REGION |
AWS region (e.g., us-east-2) | Yes |
The application deploys to AWS using CloudFormation. The CloudFormation template is located in aws/cf_create_stack.json.
Ensure you have AWS CLI configured with appropriate credentials:
aws configureDeploy using the CloudFormation template:
aws cloudformation deploy \
--template-file aws/cf_create_stack.json \
--stack-name ${STACK_NAME} \
--region ${AWS_REGION} \
--capabilities CAPABILITY_IAMThe deployment happens automatically when code is pushed to the main branch. The pipeline will:
- Delete existing stack (if any)
- Wait for deletion to complete
- Deploy new stack using CloudFormation