flightcontrol

Example Project from A First Look at Flightcontrol

Flightcontrol Config

Flightcontrol contains its own infrastructure as code specification that is used in a flightcontrol.json file.

{
  "environments": [
    {
      "id": "production",
      "name": "Production",
      "region": "us-west-2",
      "source": {
        "branch": "main"
      },
      "services": [
        {
          "id": "my-webapp",
          "name": "my-webapp",
          "type": "fargate",
          "cpu": 0.5,
          "memory": 1024,
          "minInstances": 1,
          "maxInstances": 1,
          "buildCommand": "npm i",
          "startCommand": "node index.js",
          "envVariables": {
            "APP_ENV": "production"
          },
          "port": 8080
        }
      ]
    }
  ]
}

Node project with an Express server

We have a boilerplate Node application with Express that returns an HTML fragment.

// index.js

const express = require("express")
const app = express()

const PORT = 8080
const HOST = '0.0.0.0'

app.get('/', (req, res) => {
  res.send('<h2>ajcwebdev-docker</h2>')
})

app.listen(PORT, HOST)
console.log(`Running on http://${HOST}:${PORT}`)

Run server

node index.js

Container image

You'll need to build a Docker image of your app to run this app inside a Docker container using the official Docker image.

Dockerfile

Docker can build images automatically by reading the instructions from a Dockerfile. A Dockerfile is a text document that contains all the commands a user could call on the command line to assemble an image. Using docker build users can create an automated build that executes several command-line instructions in succession.

FROM node:14-alpine
LABEL org.opencontainers.image.source https://github.com/ajcwebdev/ajcwebdev-docker
WORKDIR /usr/src/app
COPY package*.json ./
RUN npm i
COPY . ./
EXPOSE 8080
CMD [ "node", "index.js" ]

Build project with docker build

The docker build command builds an image from a Dockerfile and a "context". A build’s context is the set of files located in the specified PATH or URL. Go to the directory with your Dockerfile and build the Docker image.

docker build . -t ajcwebdev-docker

The -t flag lets you tag your image so it's easier to find later using the docker images command.

List Docker images with docker images

Your image will now be listed by Docker. The docker images command will list all top level images, their repository and tags, and their size.

docker images

Run the image

Docker runs processes in isolated containers. A container is a process which runs on a host. The host may be local or remote.

Run Docker container with docker run

When an operator executes docker run, the container process that runs is isolated in that it has its own file system, its own networking, and its own isolated process tree separate from the host.

docker run -p 49160:8080 -d ajcwebdev/ajcwebdev-docker

-d runs the container in detached mode, leaving the container running in the background. The -p flag redirects a public port to a private port inside the container.

List containers with docker ps

To test your app, get the port of your app that Docker mapped:

docker ps

Print output of app with docker logs

docker logs <container id>

Call app using curl

curl -i localhost:49160