README
SnoopLogg
Laid back debug logging.
Installation
npm install snooplogg
Features
- Built-in and custom log types
- Ability to snoop on other snooplogg instances nested in dependencies
- Pipe messages to one or more streams
- Namespacing
- Filter messages using the
DEBUG
(orSNOOPLOGG
) environment variable - Automatic color selection with brightness range
- Exports chalk library for your convenience.
- Similar API to TJ's debug:
Examples
debug
style:
// app.js
import snooplogg from 'snooplogg';
import http from 'http';
// const debug = require('debug')('http');
const debug = snooplogg('http').log;
const name = 'My App';
debug('booting %o', name);
http.createServer((req, res) => {
debug(`${req.method} ${req.url}`);
res.end('hello\n');
}).listen(3000, () => debug('listening'));
// worker.js
import snooplogg from 'snooplogg';
const a = snooplogg('worker:a');
const b = snooplogg('worker:b');
/*
Or you could do this:
const worker = snooplogg('worker');
const a = worker('a');
const b = worker('b');
*/
function work_a() {
a('doing lots of uninteresting work');
setTimeout(work_a, Math.random() * 1000);
}
work_a();
function work_b() {
b('doing some work');
setTimeout(work_b, Math.random() * 2000);
}
work_b();
Standard console usage:
import log from 'snooplogg';
log.trace('bow'); // writes to stdout/stderr if DEBUG matches + all pipes
log.info('wow')
.warn('wow')
.error('wow');
Namespace support:
import snooplogg from 'snooplogg';
const log = snooplogg('myapp');
log.info('bow', 'wow', 'wow'); // writes to stdout/stderr if DEBUG=myapp + all pipes
Stream output to stdout:
import snooplogg from 'snooplogg';
const log = snooplogg.stdio('yippy yo');
log.info('bow', 'wow', 'wow'); // writes to stdout/stderr + all pipes
const log = snooplogg.enable('*')('yippy yay');
log.info('bow', 'wow', 'wow'); // writes to stdout/stderr + all pipes
Pipe output to a stream (such as a file or socket):
import snooplogg from 'snooplogg';
const log = snooplogg
.pipe(someWritableStream);
log.info('yippy', 'yo');
Listen for messages from all SnoopLogg
instances, even from other dependencies:
import snooplogg, { snoop } from 'snooplogg';
snoop();
const log = snooplogg('bumpin');
log('one');
log
.trace('two')
.debug('three')
.info('and to the four');
log.warn(`It's like this`);
log.error('and like that');
log.fatal('and like this');
Custom log types:
import snooplogg, { type } from 'snooplogg';
type('jin', { color: 'cyan' });
type('juice', { color: 'yellow' });
const log = snooplogg();
log.jin('parents ain\'t home');
log.juice('too much drama', true);
Console:
import snooplogg from 'snooplogg';
snooplogg.enable('*').console.log('dawg gone');
API
snooplogg()
Creates a namespaced logger as well as defines the global namespaced logger.
snooplogg.log(msg)
Outputs a message using the standard console.log()
format syntax.
snooplogg.config(options)
Allows you to set various instance specific options.
colors
- (Array) An array of color names to choose from when auto-selecting a color, specifically for rendering the namespace.minBrightness
- (Number) The minimum brightness to auto-select a color. Value must be between 0 and 255 as well as less than or equal to themaxBrightness
. Defaults to80
.maxBrightness
- (Number) The maximum brightness to auto-select a color. Value must be between 0 and 255 as well as greater than or equal to theminBrightness
. Defaults to210
.theme
- (String) The name of the default theme to use. Defaults tostandard
.maxBufferSize
- (Number) The maximum number of log lines to buffer. Used to flush prior messages to new pipes.
Returns the original SnoopLogg
instance.
Enabling Logging
By default, Snooplogg only prints messages if the the DEBUG
or SNOOPLOGG
environment variables
are set.
# macOS and Linux
$ DEBUG=izzle node loggfather.js
# Windows PowerShell
> $Env:DEBUG="izzle" node loggfather.js
# Windows Command Prompt
> set DEBUG=izzle
> node loggfather.js
Note: You may also use the
SNOOPLOGG
environment variable to avoid conflicts with other libraries that use debug
You can also use any environment variable you want by simply calling enable()
before logging.
import snooplogg from 'snooplogg';
// change the global environment variable name
snooplogg.enable(process.env.LOGGFATHER);
Note: The console log types (
info
,warn
,error
, etc) are for display only.snooplogg
does not support log level filtering, only namespace filtering via theSNOOPLOGG
(orDEBUG
) environment variable or byenable()
.
Global Defaults
SnoopLogg allows you to set defaults using environment variables that apply to all SnoopLogg instances.
SNOOPLOGG_COLOR_LIST
- A comma-separated list of supported color names.SNOOPLOGG_DEFAULT_THEME
- Sets thetheme
.SNOOPLOGG_MAX_BUFFER_SIZE
- Sets themaxBufferSize
.SNOOPLOGG_MAX_BRIGHTNESS
- Sets themaxBrightness
.SNOOPLOGG_MIN_BRIGHTNESS
- Sets theminBrightness
.
License
MIT