@MomsFriendlyDevCo/Debug

Isomorphic chainable log / debugging utility.

This module works in Node as well as the browser.

CJS

var log = require('@momsfriendlydevco/debug')('MyApp');

log('Hello World') // Will log `[MyApp] Hello World`

ESM

import Debug from '../lib/debugNode.js';
let log = Debug('MyApp');


log('Hello World') // Will log `[MyApp] Hello World`

API

The Debug function is a chainable object so any number of methods can be used in sequence.

log.as('New Context').force('Hello World') // Will log even if the current logger is disabled

Debug(prefix)

Create a new Debug instance and set its prefix.

debug(...msg)

Debug instance, output whatever input is given with the associated prefix.

See debug.log() for full details.

debug.log(...msg)

Output the message contents. This is just a convenience wrapper for debug(...msg) that makes chaining a little easier.

If the first argument is a number, it is assumed to be the verbosity level to print at.

import Debug from '../lib/debugNode.js';
let log = Debug('Foo').verbosity(1);

log('Default'); // Will output
log(1, 'One'); // Will output if verbosity >= 1
log(2, 'Two'); // Will not print as if verbosity == 1

debug.prefix(prefix)

Set a new, permanent prefix for this instance.

debug.as(prefix, ...msg?)

Set a temporary prefix for the next logging operation. This will revert to the last prefix after log() has performed an operation.

import Debug from '../lib/debugNode.js';
let log = Debug('Foo');

log('1'); // Output: [Foo] 1

log.as('Bar', '2'); // Output: [Bar] 2

log.as('Baz').log('3'); // Output: [Baz] 3

debug.warn(...msg)

Same as log() but outputs to STDERR instead of STDOUT.

debug.force(...msg)

Output even if this logger is disabled.

debug.enable(isEnabled?)

Set whether this debugger is enabled.

debug.disable(isDisabled?)

Opposite of enable()

debug.only(...msg)

Output a message (even if disabled) then disable this logger.

debug.verbosity(level)

Set the verbosity level of the debugging component.

debug.highlight(match, color, options)

Add a highlighting option to add color / special characters to matched text.

Match is a RegExp to match against and color is the function to use to decorate the match.

If capture groups are used they are passed as the arguments to the function in order, if no capture groups are present the entire matching string is highlighted.

let log = Debug('Highlighting')
log.highlight(/SKU:\d{3,6}/g, log.colors.blue, {prefix: '▷', suffix: '◁'});

log('Should highlight SKUs like SKU:123, SKU:66666 & SKU:123456');

Options are:

Option	Type	Default	Description
prefix	string	''	Optional prefix to add to the match
suffix	string	''	Optional suffix to add to the match

debug.new(prefix)

Create a new debugger based on the given prefix.

debug.clone(prefix)

Create a new debugger based on the given prefix but also copy over all existing settings.

debug.diff(options)

Selectively log the differences between two objects.

Options are:

|Name | Types | Default | Description | |--------------| ------------------------- | ---------| |log | function | this | Log output function to use, must provide color library as .colors subkey | |original | Object | | Original, pristine value to examine | |originalVia | function | | Optional function to run original via before diffing. Called as (original, settings) | |updated | Object | | Updated value, provide either this OR merge key | |updatedVia | function | | Optional function to run updated (or merged) obejcts through via before diffing. Called as (updated, settings) | |merge | Object | | Value to merge with original (mutating original) | |mergeVia | function | | Function to conduct the merge of original + merge. Called as (original, merge, settings), if this function returns non-falsy that value is now used as the updated object | |prefix | string | | String to use as prefix when a diff is detected | |ignore | Array or Set | ['updated'] | Paths to ignore from output | |noChanges | string | | String to force display if no changes are present, if omitted nothing is shown | |inspect | function | utils.inspect | Inspector to use when formatting object output. Called as (thing, settings) | |formatter | function | | Function to use for formated output. Called as (diff, settings) |

debug.colors

Only available to Node instances. Instance of Chalk to easily wrap coloring.

import Debug from '../lib/debugNode.js';
let log = Debug('MyApp', log.colors.red('Red'), log.colors.white('White'), log.colors.blue('Blue'));

debug.enabled

Boolean indicating if this debugger is enabled.