dnssd/lib/debug.js

Bonjour/Avahi-like service discovery in pure JavaScript

'use strict';

var misc = require('./misc');

var enabledNamespaces = [];
var disabledNamespaces = [];

var enabledVerbose = [];
var disabledVerbose = [];

var colors = ['blue', 'green', 'magenta', 'yellow', 'cyan', 'red'];
var colorsIndex = 0;

var noop = function noop() {};
noop.verbose = noop;
noop.v = noop;
noop.isEnabled = false;
noop.verbose.isEnabled = false;
noop.v.isEnabled = false;

var logger = console.log;

// initialize
if (process.env.DEBUG) {
  process.env.DEBUG.replace(/\*/g, '.*?').split(',').filter(function (s) {
    return !!s;
  }).forEach(function (namespace) {
    namespace.substr(0, 1) === '-' ? disabledNamespaces.push(namespace.substr(1)) : enabledNamespaces.push(namespace);
  });
}

if (process.env.VERBOSE) {
  process.env.VERBOSE.replace(/\*/g, '.*?').split(',').filter(function (s) {
    return !!s;
  }).forEach(function (namespace) {
    namespace.substr(0, 1) === '-' ? disabledVerbose.push(namespace.substr(1)) : enabledVerbose.push(namespace);
  });
}

function namespaceIsEnabled(name) {
  if (!enabledNamespaces.length) return false;

  function matches(namespace) {
    return name.match(new RegExp('^' + namespace + '$'));
  }

  if (disabledNamespaces.some(matches)) return false;
  if (enabledNamespaces.some(matches)) return true;

  return false;
}

function namespaceIsVerbose(name) {
  if (!enabledVerbose.length) return false;

  function matches(namespace) {
    return name.match(new RegExp('^' + namespace + '$'));
  }

  if (disabledVerbose.some(matches)) return false;
  if (enabledVerbose.some(matches)) return true;

  return false;
}

function timestamp() {
  var now = new Date();

  var time = [misc.padStart(now.getHours(), 2, '0'), misc.padStart(now.getMinutes(), 2, '0'), misc.padStart(now.getSeconds(), 2, '0'), misc.padStart(now.getMilliseconds(), 3, '0')];

  return '[' + time.join(':') + ']';
}

/**
 * Returns debug fn if debug is enabled, noop if not
 *
 * @param  {string} namespace
 * @return {function}
 */
module.exports = function debug(namespace) {
  if (!namespaceIsEnabled(namespace)) return noop;

  // shorten Zeroconf:filename.js -> filename… becuase its driving me crazy
  var shortname = namespace.replace('dnssd:', '');
  if (shortname.length > 10) shortname = shortname.substr(0, 9) + '…';
  if (shortname.length < 10) shortname = misc.pad(shortname, 10);

  var color = colors[colorsIndex++ % colors.length];
  var prefix = misc.color('•' + shortname, color);

  function logFn(msg) {
    // '•Query.js [10:41:54:482] '
    var output = prefix + ' ' + misc.color(timestamp(), 'grey') + ' ';

    for (var _len = arguments.length, args = Array(_len > 1 ? _len - 1 : 0), _key = 1; _key < _len; _key++) {
      args[_key - 1] = arguments[_key];
    }

    output += misc.format.apply(misc, [msg].concat(args));

    logger(output);
  }

  logFn.isEnabled = true;

  if (namespaceIsVerbose(namespace)) {
    logFn.verbose = logFn;
    logFn.v = logFn;
    logFn.verbose.isEnabled = true;
    logFn.v.isEnabled = true;
  } else {
    logFn.verbose = noop;
    logFn.v = noop;
  }

  return logFn;
};