Clone repo:

git clone https://github.com/Ar37-rs/login_page_plus_oauth2.git
cd login_page_plus_oauth2
cd backend

A note, before running:
Change the empty client_id and client_secret strings inside the main.go file according to your GA ClientID and ClientSecret,
for example:

const client_id = "574732033189-17hbq0na03Shqr6s9hcpehhr8maudius.apps.googleusercontent.com"
const client_secret = "GOCSPD-rRvgd1RfhrjgyUQ5zOppYTCA1hQS"

and also you have to add the url: http://localhost:1323/auth/oauth2 as one of your Authorised redirect URIs on your GA credential config.
for more info visit: https://console.cloud.google.com/apis/credentials

How to run (the SPA and database/sqlite3 are already included and configured):

go mod tidy
go run main.go

and then open http://localhost:1323