Why is process not exiting and how to get it to exit

Question

I have a server I want to run (on one HTTP port), and then another script (which runs (temporarily) on another port).

I'm using a pipe in order to let these run concurrently, and brackets to group the commands such that sleep occurs first (the second script accesses the server started in the first, so there needs to be some time for the first to be set up).

It works fine, with the server getting started and the sleep and test file executing correctly thereafter, but the terminal process does not exit automatically after the test as it does when just running the script.

npm run start-json-server | { sleep 1; node './test/index-cjs.js' ; }

What do I need to do to allow a natural exit (preferably without going through the trouble of finding the process and killing it)?

Update: I realized it was still running (duh) because the first script, as a server, doesn't terminate... But is there a way I can get it to terminate, again, preferably without finding its PID?

Answer 1

A pipe is not used for starting concurrent processes. It does do that, but it's mainly used for setting up a data stream between two stages of a pipeline.

Instead of your pipeline, use

npm run start-json-server &
server_pid="$!"

sleep 1

node ./test/index-cjs.js

kill "$server_pid"

This would start the first command in the background. There would then be a one second delay before the second command is started. When the second command finishes, the first command is killed.

The PID of the most recently started background process (a process started by using & at the end of it) is available as "$!", and here we use that fact to keep track of the PIDs of the first command.