trezor-link/lib/lowlevel/protobuf/message_decoder.js

Trezor Link for browser

"use strict";

// Helper module for converting Trezor's raw input to
// ProtoBuf's message and from there to regular JSON to trezor.js

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.MessageDecoder = undefined;

var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();

var _protobufjsOldFixedWebpack = require("protobufjs-old-fixed-webpack");

var ProtoBuf = _interopRequireWildcard(_protobufjsOldFixedWebpack);

var _messages = require("./messages.js");

function _interopRequireWildcard(obj) { if (obj && obj.__esModule) { return obj; } else { var newObj = {}; if (obj != null) { for (var key in obj) { if (Object.prototype.hasOwnProperty.call(obj, key)) newObj[key] = obj[key]; } } newObj.default = obj; return newObj; } }

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

var ByteBuffer = ProtoBuf.ByteBuffer;
var Long = ProtoBuf.Long;

var MessageDecoder = exports.MessageDecoder = function () {
  // message type number
  function MessageDecoder(messages, type, data) {
    _classCallCheck(this, MessageDecoder);

    this.type = type;
    this.data = data;
    this.messages = messages;
  }

  // Returns an info about this message,
  // which includes the constructor object and a name

  // raw data to push to Trezor

  // Builders, generated by reading config


  _createClass(MessageDecoder, [{
    key: "_messageInfo",
    value: function _messageInfo() {
      var r = this.messages.messagesByType[this.type];
      if (r == null) {
        throw new Error("Method type not found - " + this.type);
      }
      return new MessageInfo(r.constructor, r.name);
    }

    // Returns the name of the message

  }, {
    key: "messageName",
    value: function messageName() {
      return this._messageInfo().name;
    }

    // Returns the actual decoded message, as a ProtoBuf.js object

  }, {
    key: "_decodedMessage",
    value: function _decodedMessage() {
      var constructor = this._messageInfo().messageConstructor;
      return constructor.decode(this.data);
    }

    // Returns the message decoded to JSON, that could be handed back
    // to trezor.js

  }, {
    key: "decodedJSON",
    value: function decodedJSON() {
      var decoded = this._decodedMessage();
      var converted = messageToJSON(decoded);

      return JSON.parse(JSON.stringify(converted));
    }
  }]);

  return MessageDecoder;
}();

var MessageInfo = function MessageInfo(messageConstructor, name) {
  _classCallCheck(this, MessageInfo);

  this.messageConstructor = messageConstructor;
  this.name = name;
};

// Converts any ProtoBuf message to JSON in Trezor.js-friendly format


function messageToJSON(message) {
  var res = {};
  var meta = message.$type;

  var _loop = function _loop(key) {
    var value = message[key];
    if (typeof value === "function") {
      // ignoring
    } else if (value instanceof ByteBuffer) {
      var hex = value.toHex();
      res[key] = hex;
    } else if (value instanceof Long) {
      var num = value.toNumber();
      res[key] = num;
    } else if (Array.isArray(value)) {
      var decodedArr = value.map(function (i) {
        if (typeof i === "object") {
          return messageToJSON(i);
        } else {
          return i;
        }
      });
      res[key] = decodedArr;
    } else if (value instanceof ProtoBuf.Builder.Message) {
      res[key] = messageToJSON(value);
    } else if (meta._fieldsByName[key].type.name === "enum") {
      if (value == null) {
        res[key] = null;
      } else {
        var enumValues = meta._fieldsByName[key].resolvedType.getChildren();
        res[key] = enumValues.find(function (e) {
          return e.id === value;
        }).name;
      }
    } else {
      res[key] = value;
    }
  };

  for (var key in message) {
    _loop(key);
  }
  return res;
}