Simple Logging Facade
npm install slfbash
npm install --save slf
`
API
Get a logger
`javascript
import { LoggerFactory } from 'slf';
const log = LoggerFactory.getLogger('name');
const log = LoggerFactory.getLogger('name:subname:subsubname');
`
$3
`javascript
log('Hello!'); // As level info
log.log('info', 'Hello!'); // as level info
log.log('Hello!'); // as level info (implicit)
log.trace('My Trace');
log.debug('My Debug');
log.info('My Info');
log.warn('My Warning');
log.error('My Error');
log.critical('My Critical Error');
`
$3
Using util.format(...)
- %s - String.
- %d - Number (both integer and float).
- %j - JSON. Replaced with the string '[Circular]' if the argument contains circular references.
- %% - single percent sign ('%'). This does not consume an argument.
`javascript
log.info('My Formatted %s', 'Message')
>> 'My Formatted Message'
log.info('My Formatted %d', 123)
>> 'My Formatted 123'
log.info('My Formatted %d', 123)
>> 'My Formatted 123'
`
Json Formatting
`javascript
log.info({ a: 'aloha' })
>> { a: 'aloha' }
log.info('My Formatted %d', 123)
>> 'My Formatted 123'
log.info('My Formatted %d', 123)
>> 'My Formatted 123'
`
Configuring a Provider
`javascript
LoggerFactory.setFactory();
LoggerFacotry.setFactory(ConsoleLogger);
`
$3
When setting a factory provider, you can also set a level to ensure not to send logs if the level is too low.
#### Set Level
`javascript
LoggerFacotry.setFactory(ConsoleLogger, Level.Info);
`
#### Hierarchy
- Critical
- Error
- Warn
- Info
- Debug
Writing a Provider
SLF is nothing without a backing logging implementation.
The most tiny implementation of a console.log based implementation is shipped with SLF
$3
factory-function has the following signature:
`javascript
function(loggerName) {
return function(event) {
//do something with logEvent
}
}
event = {
timeStamp: 123456767,
params: [],
name: 'logger:name'
level: 'error'
}
``