README.md•2.53 kB
# why-is-node-running
Node is running but you don't know why? `why-is-node-running` is here to help you.
## Installation
Node 8 and above:
```bash
npm i why-is-node-running -g
```
Earlier Node versions (no longer supported):
```bash
npm i why-is-node-running@v1.x -g
```
## Usage
```js
const log = require('why-is-node-running') // should be your first require
const net = require('net')
function createServer () {
const server = net.createServer()
setInterval(function () {}, 1000)
server.listen(0)
}
createServer()
createServer()
setTimeout(function () {
log() // logs out active handles that are keeping node running
}, 100)
```
Save the file as `example.js`, then execute:
```bash
node ./example.js
```
Here's the output:
```
There are 5 handle(s) keeping the process running
# Timeout
/home/maf/dev/node_modules/why-is-node-running/example.js:6 - setInterval(function () {}, 1000)
/home/maf/dev/node_modules/why-is-node-running/example.js:10 - createServer()
# TCPSERVERWRAP
/home/maf/dev/node_modules/why-is-node-running/example.js:7 - server.listen(0)
/home/maf/dev/node_modules/why-is-node-running/example.js:10 - createServer()
# Timeout
/home/maf/dev/node_modules/why-is-node-running/example.js:6 - setInterval(function () {}, 1000)
/home/maf/dev/node_modules/why-is-node-running/example.js:11 - createServer()
# TCPSERVERWRAP
/home/maf/dev/node_modules/why-is-node-running/example.js:7 - server.listen(0)
/home/maf/dev/node_modules/why-is-node-running/example.js:11 - createServer()
# Timeout
/home/maf/dev/node_modules/why-is-node-running/example.js:13 - setTimeout(function () {
```
**Important Note!**
`unref`ed timers do not prevent the Node process from exiting. If you are running with Node v11.0.0 and above, `unref`ed timers will not be listed in the above list. Unfortunately, this is not supported in node versions below v11.0.0.
## CLI
You can also run `why-is-node-running` as a standalone if you don't want to include it inside your code. Sending `SIGUSR1`/`SIGINFO` signal to the process will produce the log. (`Ctrl + T` on macOS and BSD systems)
```bash
why-is-node-running /path/to/some/file.js
```
```
probing module /path/to/some/file.js
kill -SIGUSR1 31115 for logging
```
To trigger the log:
```
kill -SIGUSR1 31115
```
## Require CLI Option
You can also use the node `-r` option to include `why-is-node-running`:
```bash
node -r why-is-node-running/include /path/to/some/file.js
```
The steps are otherwise the same as the above CLI section
## License
MIT