squawk-wall

A demonstration app for Microservices with NodeJS, MongoDB, Docker, and Kubernetes that can run on your local development system. Uses Next JS with SSR (server side rendering) for the front end.

Installation

git clone https://github.com/kurtvandusen/squawk-wall
cd squawk-wall/Comments-Microservice
npm install
cd ../Front-End-Microservice
npm install
cd ../Posts-Microservice
npm install
cd ../Query-Microservice
npm install

Set-up Environment

You will need Docker, Kubernetes, Skaffold and Ingress Nginx installed in your development environment.

Install Docker Desktop on Windows or MacOS. Install Docker on Linux.

Install Kubernetes on Linux

Install Skaffold

Install Ingress Nginx

Customize local hosts file

You will also need to customize your local hosts file to point to squawk-wall.dev to your localhost IP address.

Windows: c:\Windows\System32\Drivers\etc\hosts

macOS and Linux: /etc/hosts

Open your hosts file and add the following line at the bottom: 127.0.0.1 squawk-wall.dev

Runnning the Microservices Locally in Development Mode

Start Docker and Kubernetes on your development system.

Deploy Ingress Nginx kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/controller-v1.5.1/deploy/static/provider/cloud/deploy.yaml

From a terminal in the root dirctory of squawk-wall, run the following command: skaffold dev

Allow time for all of the services to start and connect. Stop any pods which fail to connect. They will restart automatically.

Open your browser and navigate to http://squawk-wall.dev/. You may get a security warning. To bypass this in chrome, type "thisisunsafe" directly in the browser window.

Building your own Docker images (optional)

Create an account for Docker Hub and login from your CLI. Note: Replace "your-user-name" below with your Docker Hub user name.

From root directory:

cd Comments-Microservice
docker build -t your-user-name/squawk-wall-comments .
docker push your-user-name/squawk-wall-comments
cd ../Front-End-Microservice
docker build -t your-user-name/squawk-wall-front-end .
docker push your-user-name/squawk-wall-front-end
cd ../Posts-Microservice
docker build -t your-user-name/squawk-wall-posts .
docker push your-user-name/squawk-wall-posts
cd ../Query-Microservice
docker build -t your-user-name/squawk-wall-query .
docker push your-user-name/squawk-wall-query

Update the skaffold.yaml and the config/k8s/ -depl.yaml files by replacing "kurtvandusen" with your Docker user name.

API Documentation

openAPI yaml generated with Stoplight

Microservice App Architecture

Kubernetes Architecture

Database per Microservice Pattern

Cannonical Authority

Note on concurrency issues with async events based communication:

• Each microservice is a canonical authority for the data it controls.
• No other microservice can create, update, read or destroy that data.
• Microservices share the data they control by emitting events to the event bus.

To Do

• Add Search component to Front-End using the Query microservice.