Go Auto-Recompile and Reload Server on file change

Question

I know AppEngine does this, but I\'m not coding for it.

I tried using Guard from Ruby world, to listen on changes on .go files, and execut

Answer 1

if anyone’s still looking for a solution, i wrote some shell scripts to do this and it’s usable via a docker environment, the repos at https://github.com/zephinzer/golang-dev

Answer 2

A friend wrote a simple Compile Daemon for go, worked like a charm for my own small net/http-projects.

You can find the repository here: https://github.com/githubnemo/CompileDaemon

Answer 3

You can use nodemon for this. Simply create a nodemon.json file containing your configuration, files to watch, files to ignore, and command to execute when a file changes. Something like this configuration.

nodemon.json

{
  "watch": ["*"],
  "ext": "go graphql",
  "ignore": ["*gen*.go"],
  "exec": "go run scripts/gqlgen.go && (killall -9 server || true ) && go run ./server/server.go"
}

You do require nodejs for this to work.
But its far better then any other tool I've used so far that are go specific.

Answer 4

I've recently discovered a reflex tool. It's fast and works like a charm. It is very similar to nodemon (from nodejs world) and guard (from ruby world).

Most of the time I'm using it similar to below:

reflex -d none -s -R vendor. -r \.go$ -- go run cmd/server/main.go

But it maybe more convenient to have it's options in a file like .reflex, with contents like this:

-d none -s -R vendor. -r \.go$

So then you just run it like this

reflex $(cat .reflex) -- go run cmd/server/main.go

You can do same thing to "hot reload" tests:

reflex $(cat .reflex) -- go test ./... -v

There is also a config option where you can specify a number of commands you run same time, but I don't really use it.

Answer 5

After scrolling through the internet in search of a simple solution that was using standard linux tools (inotify & bash), I ended up creating this simple bash script that does the job.

I tested it in a container running golang:1.12 and using go run . to serve files. read the script before using it, as it kills the go run processes depending on a folder name, and if there are conflicts with other processes that you run it might kill them.

#!/bin/bash

go run . &
while inotifywait --exclude .swp -e modify -r . ;
do
    # find PID of the file generated by `go run .` to kill it. make sure the grep does not match other processes running on the system
    IDS=$(ps ax | grep "/tmp/go-build" | grep "b001/exe/main" | grep -v "grep" | awk '{print $1}')
    if [ ! -z "$IDS" ]
    then
        kill $IDS;
    fi
    go run . &
done;

Answer 6

Another option, if you have nodejs installed on your machine

install nodemon with -g npm i -g nodemon

go to your code dir and run:

nodemon --watch './**/*.go' --signal SIGTERM --exec 'go' run cmd/MyProgram/main.go

This will send SIGTERM every time any .go files changes and will run go run cmd/Myprogram/main.go

Fully cross platform.