【每日一题】– 2019-10-25 - 如果一个 Node.js 进程已经启动，没有添加 --inspect 参数，我们不想重启（会丢失现场）又想调试怎么办？

[azl397985856]

node --inspect app.js 可以用来调试应用，但是需要在一开始启动的时候指定--inspect参数，如果一个 Node.js 进程已经启动该怎么办？

[azl397985856]

Intuition

Actually, if u'r familiar with attach mode in VSCode, it will be very comfortable for u.

Two Ways

Below is the detailed info:

1. node -e

-e, --eval=... evaluate script

node -e 'process._debugProcess(30464)'

2. system signal

$ kill -SIGUSR1 30464

• relative question: https://stackoverflow.com/questions/13052548/node-js-how-to-attach-to-a-running-process-and-to-debug-the-server-with-a-conso

• relative post: https://hackernoon.com/debugging-node-without-restarting-processes-bd5d5c98f200