aws-ecs-go-web-api

README

Quick start

Configuration

This service is configured using environment variables using github.com/kelseyhightower/envconfig Envconfig supports the use of struct tags to specify alternate, default, and required environment variables.

Given the following config struct

	var cfg struct {
		Env  string `default:"dev" envconfig:"ENV"`
		Service struct {
			Name            string        `default:"web-api" envconfig:"SERVICE_NAME"`
        },
    }

    envPrefix := "WEB_API"
	if err := envconfig.Process(envPrefix, &cfg); err != nil {
		log.Fatalf("main : Parsing Config : %+v", err)
	}

Envconfig will process value for cfg.Env by first trying to populate it with the value for WEB_API_ENV. If WEB_API_ENV is not set, it will then check for ENV. If envconfig can't find an environment variable value for either key, it will populate it with "dev" as the default value.

cfg.Service.Name will be populated by checking for the environment variable using the following using WEB_API_SERVICE_NAME. If that is not set, it will then check SERVICE_NAME or set the default value to "web-api".

Building

This service uses a multi-stage Dockerfile. Since most projects will have additional packages that are contained in a parent directory from the service itself, the service must be built from the project root directory and reference the Dockerfile for the target service.

docker build -f examples/aws-ecs-go-web-api/Dockerfile .

Hot reloads

When using docker-compose to run the services, it's a pain to manually stop/start the service to see your code changes. This service using a multi-stage docker build and uses github.com/gravityblast/fresh as the entrypoint for the target layer dev. The docker-compose.yaml config file references layer with target: dev and mounts the source code for the project as a volume. Fresh with then monitor your code base and (re)starts your service everytime you save a Go or template file.

Fresh using the configuration file fresh-auto-reload.conf