Rat Signal Part 5: Deployment

August 2, 2020

Docker makes it insanely easy to deploy microservice-based applications. Docker is used to create “containerized” services. These containers are similar to traditional virtual machines but are more lightweight and easier to deploy and network together.

Dockerfiles

A Dockerfile is a set of instructions used to deploy a Docker container. This is the Dockerfile used in the Endpoint service:

FROM node:12.18.3-alpine

WORKDIR /usr/src/app

COPY package*.json ./

RUN npm install

COPY . .

EXPOSE 8080

CMD npm run dev:start

This tells Docker to base the new image off of an image of Alpine Linux with Node and NPM preinstalled. A working directory is set, package.json is copied over, the node dependencies are installed, the source code is copied over, and the code is built. Once deployed to a container, the server is automatically run.

Docker Compose

Docker Compose is used to coordinate deployment of all of the services used in a microservice-based application. It’s an absolutely beautiful and elegant symphony of tasks. This is Rat Signal’s Compose file:

version: '3.8'

services:

  broker:
    image: eclipse-mosquitto:1.6.10
    restart: on-failure
    ports:
      - "1883:1883"
      - "9001:9001"
    networks:
      rat-net:
        aliases:
          - broker
    volumes:
      - "./broker/mosquitto.conf:/mosquitto/config/mosquitto.conf"

  middleman:
    image: nodered/node-red:1.1.2
    restart: on-failure
    ports:
      - "1880:1880"
    networks:
      rat-net:
        aliases:
          - middleman
    volumes:
      - "./middleman:/data"

  endpoint:
    build: ./endpoint
    ports: 
        - "8080:8080"
    networks:
      rat-net:
        aliases:
          - endpoint

networks:
  rat-net:

Home Server Deployment

All of the code for Rat Signal lives in my Github repository. To deploy Rat Signal to my home server, all I have to is SSH into the server, clone the code, and run docker-compose up. Docker handles all of the heavy lifting. That’s it!

The back-end server software is now complete. Next up, the front-end hardware.

The Rat Signal Series: