serverquery/lib/serializer.js

Low level TeamSpeak™ 3 ServerQuery protocol implementation

const LIST_DELIMETER =  '|';
const LIST_DELIMETER_REGEX = /\|/g;

const PARAMS_DELIMETER = ' ';
const PARAMS_DELIMETER_REGEX = / +/g;

const ASSIGNMENT = '=';
const ASSIGNMENT_REGEX = /^(\w+)(?:=(.*))?$/;

const INTEGER_REGEX = /^[0-9]+$/;
const FLOAT_REGEX = /^[0-9]+.[0-9]+$/;


/**
 * Escape a string.
 * @param {String} str
 * Adapted from: https://github.com/gwTumm/node-teamspeak/blob/master/index.js
 */

export function escape(str) {
  return String(str)
    .replace(/\\/g, '\\\\')   // Backslash
    .replace(/\//g, '\\/')    // Slash
    .replace(/\|/g, '\\p')    // Pipe
    .replace(/\n/g, '\\n')    // Newline
    .replace(/\r/g, '\\r')    // Carriage Return
    .replace(/\t/g, '\\t')    // Tab
    .replace(/\v/g, '\\v')    // Vertical Tab
    .replace(/\f/g, '\\f')    // Formfeed
    .replace(/ /g,  '\\s');   // Whitespace
}


/**
 * Unescape a string.
 * @param {String} str
 * Adapted from: https://github.com/gwTumm/node-teamspeak/blob/master/index.js
 */

export function unescape(str) {
  return String(str)
    .replace(/\\s/g,  ' ')	  // Whitespace
    .replace(/\\p/g,  '|')    // Pipe
    .replace(/\\n/g,  '\n')   // Newline
    .replace(/\\f/g,  '\f')   // Formfeed
    .replace(/\\r/g,  '\r')   // Carriage Return
    .replace(/\\t/g,  '\t')   // Tab
    .replace(/\\v/g,  '\v')   // Vertical Tab
    .replace(/\\\//g, '\/')   // Slash
    .replace(/\\\\/g, '\\');  // Backslash
}


/**
 * Serialize a key: camelCase -> snake_case
 * @param {String} key
 */

export function serializeKey(key) {
  return key
    .replace(/[a-z][A-Z]/g, match => match[0] + '_' + match[1].toLowerCase());
}


/**
 * Deserialize a key: snake_case -> camelCase
 * @param {String} key
 */

export function deserializeKey(key) {
  return key
    .replace(/_[a-z]/g, match => match[1].toUpperCase());
}


/**
 * Serialize a value.
 * @param {String|[String]} value
 */

export function serializeValue(value) {
  if (value instanceof Array) {
    return value.map(escape).join('|');
  }

  return escape(value);
}


/**
 * Deserialize a value.
 * @param {String} value
 */

export function deserializeValue(value) {
  // parse as number, if it is number like
  if (INTEGER_REGEX.test(value)) {
    return Number.parseInt(value, 10);
  }
  if (FLOAT_REGEX.test(value)) {
    return Number.parseFloat(value);
  }

  return unescape(value);
}


/**
 * Serialize a command.
 * @param {String}   cmd
 * @param {[String]} flags
 * @param {Object}   params
 */

export function serializeCommand(cmd, flags, params) {
  if (flags.length) {
    cmd += ' -' + flags.join(' -');
  }

  params = Object.keys(params)
    .map(k => `${serializeKey(k)}=${serializeValue(params[k])}`)
    .join(' ');

  if (params) {
    cmd += ' ' + params;
  }

  return cmd + '\r\n';
}


/**
 * Parse a response.
 * @param {String} response
 * @param {Boolean} skipListCheck
 */

export function parseResponse(response, skipListCheck = false) {
  // got a list as response
  if (!skipListCheck && LIST_DELIMETER_REGEX.test(response)) {
    return response
      .split(LIST_DELIMETER_REGEX)
      .map(item => parseResponse(item, true));
  }

  let fields = Object.create(null);

  response
    .split(PARAMS_DELIMETER_REGEX)
    .forEach(pair => {
      let [, key, value] = pair.match(ASSIGNMENT_REGEX);

      if (value) {
        fields[deserializeKey(key)] = deserializeValue(value);
      } else {
        fields[deserializeKey(key)] = null;
      }
    });

  return fields;
}