Bash trap a nodejs application - useful for docker

entrypoint

#!/usr/bin/env bash

set -e

sig_handler() {
    exit_status=$?  # Eg 130 for SIGINT, 128 + (2 == SIGINT)
    if [[ exit_status -gt 0 ]]; then
      cat <<EOF
      !!!
      WARN: signal [$exit_status] recieved by entrypoint ... returning it"
      !!!
EOF
    else
      echo "INFO: signal [$exit_status] recieved by entrypoint ... returning it"
    fi;
    exit "$exit_status"
}

trap sig_handler INT HUP TERM QUIT EXIT KILL

run() {
    echo "INFO: entrypoint running app.js with params ..."
    node ./test.js $@
}

run $@

test.js

const SLOW_START_DELAY=500;
const WAIT_TIME = 5000;

function start(choice) {
    // simulate "slow start"
    setTimeout(complete, WAIT_TIME, choice);
    console.log(`INFO: Running nodejs app with simulated choice ${choice} in ${WAIT_TIME}ms ...`);
    console.log(`Legend:\n--------------\n   0-10: no error \n  11-50: exception\n  51-75: error obj\n 76-100: self sigkill`)
}

function complete(choice) {
    //  0-10  no error
    // 11-50  exception
    // 51-75  error obj
    // 76-100 self sigkill
    if (choice >= 11 && choice <= 50) {
        throw "SIMULATED EXCEPTION :-D";
    } else if (choice >= 51 && choice <= 75) {
        throw new Error("SIMULATED ERROR OBJ :-D");
    } else if (choice >= 76 && choice <= 100) {
        process.kill(process.pid, 'SIGKILL');
    } else {
        console.log("INFO: app complete, exiting cleanly.");
        process.exit();
    }
}

function main() {
    var args = process.argv.slice(2);
    if ( args[0] != null ) {
        setTimeout(start, SLOW_START_DELAY, args[0])
    } else {
        var choice = Math.floor(Math.random() * 100);
        setTimeout(start, SLOW_START_DELAY, choice);
    }
    
}

main();