Swift Docker Development Template

Get started developing Swift 3 on any platform supporting Docker. Using this you can easily develop server side Swift even on a Windows computer.

Requirements

• docker
• docker-compose

Initialize a basic project scaffold:

$ docker-compose run app swift package init --type executable

SPM will generate a project from within docker container targeted the mounted volume. These files can now be accessed and edited from the host system.

Your root folder now looks like this.

.
├── Dockerfile
├── Package.swift
├── README.md
├── Sources
│   └── main.swift
├── Tests
└── docker-compose.yml

Run your project

$ docker-compose up

Creating swiftdocker_app_1
Attaching to swiftdocker_app_1
app_1  | Compile Swift Module 'app' (1 sources)
app_1  | Linking ./.build/debug/app
app_1  | Hello, world!
swiftdocker_app_1 exited with code 0

Success!

Example

Say we want to try out Vapor, the web framework for Swift.

First initialize a new SPM project, and confirm it all works with docker-compose up

Package.swift

Update your package file to look like this:

import PackageDescription

let package = Package(
    name: "app",
    dependencies: [
        .Package(url: "https://github.com/vapor/vapor.git", majorVersion: 1, minor: 5)
    ]
)

Update main.swift

import Vapor

let drop = Droplet()

drop.get("/hello") { _ in
  return "Hello Vapor"
}

drop.run()

By default Vapor runs on port 8080, so we will expose that to our host.

#docker-compose.yml
version: '2'
services: 
  app:
    build: .
    command: bash -c "swift build && ./.build/debug/app"
    volumes:
      - .:/app
    ports:
      - "8080:8080"

Now run

$ docker-compose up

You should see a bunch of output from the container while it fetches and compiles all dependencies. It now boots up the server, and by visiting localhost:8080/hello you should see activity in your console, and you will be greeted in your web browser.

From here on, start hacking in your favorite editor! Refer to docs at vapor.codes.

Production

TBD You probably want to build a different container with all the dependencies already isolated inside. At least build for production instead of debug. swift build --configuration release