This project demonstrates a pattern for graceful server shutdown in Go. It was inspired by this article: https://rudderstack.com/blog/implementing-graceful-shutdown-in-go

The sample server maintains:

• a connection to postgres database
• an HTTP webserver
• a few long-running services using PG connection

Upon startup:

• hooks on signals: SIGINT and SIGTERM to initiate a shutdown flow
• creates a global context that will be cancelled in case of shutdown
• the server connects to postgres database "test"
• starts HTTP webserver
• spawns a few goroutines that represent long-running tasks
• main thread remains blocked until one of the signals caught

Once one of the signals caught:

• it cancels the global context
• all child components will finish executing because of ctx.Done()
• the main thread unblocks receiving the error (if any)
• database is closing as the last step of shutdown

Edge cases:

• if a termination signal received upon startup sequence, it cancels the global context, and then newly creating components should start and stop pretty much immediately.
• if a termination signal received during shutdown sequence, it will be ignored.
• because SIGKILL cannot be handled, killing the server process will result in inconsistent state.

• have a postgres instance up and running on your machine
• create an empty DB "test"
• go run .
• try terminating the app by Ctrl+C (or by sending SIGINT or SIGTERM from terminal)