Nest.js 서버 안전하게 종료하기

1. SIGTERM으로 안전하게 종료해야 한다. 

참고  https://linuxhandbook.com/sigterm-vs-sigkill/ 
참고2 https://dev.to/hienngm/graceful-shutdown-in-nestjs-ensuring-smooth-application-termination-4e5n  

kill_server.sh를 수정..  -15 파라미터로 변경

pid=$(<nest_server.pid)
echo "stop nest_server (pid is $pid)"

# kill with SIGTERM
kill -15 $pid

# port 3000을 사용하는 pid에 SIGTERM을 보낸다.
# kill -15 $(lsof -i tcp:3000 | awk '{if (NR > 1) print $2}')

rm nest_server.pid

 

2. SIGTERM 받을 때, 종료 처리

Nest.js의 라이프 사이클 참고  https://docs.nestjs.com/fundamentals/lifecycle-events   onApplicationShutdown 에서 뭔가를 하면 좋을 듯..

main.ts

app.enableShutdownHooks([ShutdownSignal.SIGTERM]);

 

app.service.ts 

import { Injectable, OnApplicationShutdown } from "@nestjs/common";
import axios from 'axios';

import { mongoClient } from "./mongo_db";
import { DISCORD_WEBHOOK_URL, IS_PRODUCTION } from "./app.const";

@Injectable()
export class AppService implements OnApplicationShutdown {

    async onApplicationShutdown(signal?: string | undefined) {
        console.log(`onApplicationShutdown signal=${signal}`);
        
        console.log("mongoClient.close()")
        await mongoClient.close();

        if (IS_PRODUCTION) {
            console.log("Notify shutdown to DISCORD");
            await axios.post(DISCORD_WEBHOOK_URL, {content: "API Server shutdown"});
        }

        console.log("process exists")
    }
}