Autoreload go code on code change

For developers, the ability to autoreload code upon any changes is nothing short of a game-changer. It not only streamlines the development process but also fosters an environment of continuous improvement and experimentation.

There are so many packages for languages such as JavaScript for such a behaviour, but I struggled to easily find a simple-to-use go version with an example.

And that’s where this post comes in, as a simple to-the-point example extracted from what I learnt while reading https://dev.to/jacobsngoodwin/full-stack-memory-app-01-setup-go-server-with-reload-in-docker-62n

We will be making use of https://github.com/cespare/reflex, which is a go package and small tool to watch a directory and rerun a command when certain files change. 

I’m using this setup for an application that I am running in a docker-compose file.

The docker-compose entry looks something like this:

  api:
    restart: always
    build:
      dockerfile: ./go-reload.Dockerfile
    ports:
      - 8080:80
    command: reflex -r "\.go$$" -s -- sh -c "go run ./cmd/api/main.go"
    working_dir: /go/src/app
    volumes:
      - ./:/go/src/appCode language: JavaScript (javascript)

And the go-reload.Dockerfile file looks something like this:

FROM golang:1.20

WORKDIR /go/src/app


ENV GO111MODULE=on
RUN go install github.com/cespare/reflex@latest

And Tada, you have an easy-to-install and use auto-reloading system for your go code.