This repository contains a demo API built with go. Its main purposes are:

1. Show how the standard library may be used to build an API, and
2. Show how Docker image sizes may be minimized by using multi-stage builds.

The API listens on port 3000 and exposes a /ping endpoint for GET, POST, PUT, PATCH and DELETE HTTP requests. It responds with the values of the request's HTTP method, query parameters and body, in case there was one.

Example request:

curl --location --request POST 'localhost:3000/ping?qs1-key=qs1-value&qs2-key=qs2-value' \
  --header 'Content-Type: application/x-www-form-urlencoded' \
  --data-urlencode 'body1-key=body1-value' \
  --data-urlencode 'body2-key=body2-value'

Example response:

{
  "method": "POST",
  "queryParams": {
    "qs1-key": ["qs1-value"],
    "qs2-key": ["qs2-value"]
  },
  "body": {
    "body1-key": ["body1-value"],
    "body2-key": ["body2-value"]
  }
}

go build -o app && ./app

Three Dockerfiles have been added to the repository:

• Dockerfile.full: contains a basic setup that uses the golang:1.14.3 base image.
• Dockerfile.alpine: same setup as Dockerfile.full, but based on a golang alpine image.
• Dockerfile: uses a multi-stage build to optimize image size.

The resulting image sizes are:

• Dockerfile.full: 817MB
• Dockerfile.alpine: 378MB
• Dockerfile: 13.3MB

In order to try out the multi-stage image, you must run the following:

# Build the image
docker build -t sasalatart/go-api-demo:latest .

# Run a container
docker run -p 3000:3000 sasalatart/go-api-demo:latest

The API will then be listening on your machine's port 3000.

go test