nixfilter-uartrfid/utils.js

Filters for decoding the data sent by certain RFID readers connected via UART

'use strict';
var formats, get_data_byte_at, get_decimal, map_object, parse_data;

get_data_byte_at = function(data_string, index) {
  return parseInt(data_string.slice(index * 2, (index * 2) + 2), 0x10);
};

get_decimal = function(data_string, start_index, stop_index, number_of_digits) {
  return ('0'.repeat(number_of_digits) + parseInt(data_string.slice(start_index, stop_index), 0x10)).slice(-number_of_digits);
};

// The various output formats
formats = {
  '8H': function(data_string) {
    return data_string.slice(2, 10);
  },
  '10H>13D': function(data_string) {
    return get_decimal(data_string, 0, 10, 13);
  },
  '10H>14D': function(data_string) {
    return get_decimal(data_string, 0, 10, 14);
  },
  '10H>10D': function(data_string) {
    return get_decimal(data_string, 0, 10, 10);
  },
  '08H>10D': function(data_string) {
    return get_decimal(data_string, 2, 10, 10);
  },
  '08H>10D(int)': function(data_string) {
    return parseInt(get_decimal(data_string, 2, 10, 10));
  },
  '08H>55D': function(data_string) {
    return `${get_decimal(data_string, 2, 6, 5)},${get_decimal(data_string, 6, 10, 5)}`;
  },
  '06H>08D': function(data_string) {
    return get_decimal(data_string, 4, 10, 8);
  },
  '2.4H>3.5D(A)': function(data_string) {
    return `${get_decimal(data_string, 0, 2, 3)},${get_decimal(data_string, 6, 10, 5)}`;
  },
  '2.4H>3.5D(B)': function(data_string) {
    return `${get_decimal(data_string, 2, 4, 3)},${get_decimal(data_string, 6, 10, 5)}`;
  },
  '2.4H>3.5D(C)': function(data_string) {
    return `${get_decimal(data_string, 4, 6, 3)},${get_decimal(data_string, 6, 10, 5)}`;
  },
  '10H': function(data_string) {
    return data_string.slice(0, 10);
  },
  '2-8H': function(data_string) {
    return `${data_string.slice(0, 2)}-${data_string.slice(2, 10)}`;
  },
  'Revision': function(data_string) {
    return get_decimal(data_string, 0, 1, 2);
  },
  'Vendor': function(data_string) {
    return get_decimal(data_string, 1, 2, 2);
  }
};

// Map the object <object> according to map function <map_function> that will be called with (<value_to_map>, <key>) arguments
map_object = function(object, map_function) {
  var key, mapped_object;
  mapped_object = {};
  for (key in object) {
    mapped_object[key] = map_function(object[key], key);
  }
  return mapped_object;
};

// Parse a valid data string, returning an object with all available formats
parse_data = function(data_string) {
  return map_object(formats, function(format_function) {
    return format_function(data_string);
  });
};

// What this module exports
module.exports = {
  formats: formats,
  get_data_byte_at: get_data_byte_at,
  parse_data: parse_data
};

//# sourceMappingURL=utils.js.map