makasim / go-app-template

It's my approach to structure go files. A basic template.

go-app-template

The repo contains an app template that I use most of the time.

• It shows how to decouple app logic from main file.
• How to write unit test with mocks.
• How to write func tests.
• How to structure cli commands with Taskfile.
• Gitlab CI example.

Walk through

main.go file

The main.go file purpose is to:

• Set up logger (level, format, output and so on).
• Set up and validate app`s config (envs, json file and so on)
• Create root context.
• Create app instance, pass config and logger to it and run it.
• Handle signals. Cancel the root context.
• It must exit with status one if app.Run return an error, otherwise zero.

I put main.go file into a separate directory as a convention. All projects follow this rule and I have some scripts that rely on it.

internal directory

This is the directory for app specific packages (if there are any). No special rules. Just follow Go's advise on package naming.

internal/app directory

The application we are going to run. It should contain an App and its Config structs.

app.Run method

The method purpose is to:

• Set up any services the app needs.
• Resolve dependencies between services.
• Start all daemons, servers, workers and so on.
• Wait for the root context to be done.
• Gracefully stop services and other stuff in right order.

The app must be run synchronously from main.go file. It must block until the root context is canceled.

Unit tests

Run all tests:

task test:unit

Run some tests:

task test:unit -- ./internal/greeter/...

Filter tests:

task test:unit -- ./... -v -run TestGreeter_Greet/Hi

Func tests

Run all tests:

task test:func

Run some tests:

task test:func -- ./tests/api/...

Enter test container:

task test:func:enter
# you'll get into container shell
# you can run there several commands 
task test:func 
task test:func -- ./tests/... -v