log helpers

helpers.js

var globalize = require('globalize'),
  _ = require('underscore'),
  eyes = require('eyes'),
  conf = require('./conf')(module),
  output = conf.get('path'),
  formats = conf.get('format'),
  defaults = formats.defaults;


var helpers = exports;

// Merge here each formats with defaults
Object.keys(formats).forEach(function(format) {
  if(format !== 'defaults') formats[format] = _.extend({}, defaults, formats[format]);
});

// borrowed to cliff's inspect
helpers.inspect = eyes.inspector({ stream: null,
  styles: {               // Styles applied to stdout
    all:     null,        // Overall style applied to everything
    label:   'underline', // Inspection labels, like 'array' in `array: [1, 2, 3]`
    other:   'inverted',  // Objects which don't have a literal representation, such as functions
    key:     'grey',      // The keys in object literals, like 'a' in `{a: 1}`
    special: 'grey',      // null, undefined...
    number:  'blue',      // 0, 1, 2...
    bool:    'magenta',   // true false
    regexp:  'green'      // /\d+/
  },
  maxLength: 50
});


// ### function timestamp ()
// Returns a timestamp string for the current time, format is following [globalize date format](https://github.com/jquery/globalize#dates)
helpers.timestamp = function timestamp() {
  return globalize.format(new Date(), formats.date.format);
};

// ### function tmpl (template, data)
// tiny and micro-template utility, returns a string, depending on template string and data provided.
//
//      tmpl(':foo <p>:bar</p>', {foo: 'bar', bar: true})
//      > bar <p>true</p>
helpers.tmpl = function tmpl(s,d){ return s.replace(/:([a-z]+)/g, function(w,m){ return d[m] || ''; } );};


// ## function pad(str, padding)
//
// Basic padding function.
helpers.pad = function pad(str, options) {
  var padded = options.pad - str.length,
    elipsis = options.elipsis,
    suffix = options.suffix;

  return padded >= 0 ?
    str + new Array(padded + elipsis.length + suffix.length + 1).join(' ') :
    str.substring(0, options.pad) + elipsis + suffix;
};

helpers.padLeft = function pad(str, options) {
  var padded = options.pad - str.length,
    elipsis = options.elipsis,
    prefix = options.prefix;

  return padded >= 0 ?
    new Array(padded + elipsis.length + prefix.length + 1).join(' ') + str :
    prefix + elipsis + str.substring(str.length - options.pad, str.length);
};

helpers.format = function format(prefix, msg) {
  return helpers.tmpl(conf.get('pattern'), {
    prefix: helpers.formatProp(prefix, formats.prefix),
    msg : helpers.formatProp(msg, formats.msg)
  });
};

helpers.formatProp = function formatProp(prop, options) {
  var prefix = options.prefix,
    suffix = options.suffix,
    align = options.align;

  if(align !== 'left' && align !== 'right') {
    throw new Error('Logger: Wrong align options >> ' + align + ' for ' + prop);
  }

  // no prefix/suffix when prop is ''
  prop = prop ? prefix + prop + suffix : prop;
  if(options.pad === false) return prop;
  return helpers[align === 'left' ? 'pad' : 'padLeft'](prop, options);
};