@listener-js/log

Listener logger

!log

Install

``bash
npm install @listener-js/listener @listener-js/log
`

Enable logging

`ts
import { listener } from "@listener-js/listener"
import { log } from "@listener-js/log"

listener({ log })
`

Call logger directly

`ts
log.log([], "warn", "warning!")
// or
log.warn([], "warning!")
`

Log levels

There are six log levels: internal, trace, debug, info, warn, and error.

By default, the logger only logs messages at log level info or above. Change the log level through the LOG environment variable:

`bash
LOG=internal npm test
`

Or programmatically:

`js
log.logLevel([], "internal")
`

Listener log level

You can also set log levels for specific listener functions:

`js
log.logLevel([], "MyClass.myFn", "info")
`

Log strategies

There are three log strategies: args, argsJson, and ids (default).

Set the strategy via the LOG environment variable:

`bash
LOG=args npm test
`

To set the strategy and level, separate them with a colon (:):

`bash
LOG=trace:args npm test
`

Order does not matter when using the separator.

Log filtering

Pass a listener identifier to the LOG environment variable to filter:

`bash
LOG=MyClass.myFn npm test
`

Add a filter, strategy, and level all at once:

`bash
LOG=MyClass.myFn:args:internal npm test
``