jsmediatags/build2/XhrFileReader.js

Media Tags Reader (ID3, MP4)

'use strict';

function _typeof(obj) { "@babel/helpers - typeof"; if (typeof Symbol === "function" && typeof Symbol.iterator === "symbol") { _typeof = function _typeof(obj) { return typeof obj; }; } else { _typeof = function _typeof(obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; }; } return _typeof(obj); }

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

function _createClass(Constructor, protoProps, staticProps) { if (protoProps) _defineProperties(Constructor.prototype, protoProps); if (staticProps) _defineProperties(Constructor, staticProps); return Constructor; }

function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function"); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, writable: true, configurable: true } }); if (superClass) _setPrototypeOf(subClass, superClass); }

function _setPrototypeOf(o, p) { _setPrototypeOf = Object.setPrototypeOf || function _setPrototypeOf(o, p) { o.__proto__ = p; return o; }; return _setPrototypeOf(o, p); }

function _createSuper(Derived) { var hasNativeReflectConstruct = _isNativeReflectConstruct(); return function _createSuperInternal() { var Super = _getPrototypeOf(Derived), result; if (hasNativeReflectConstruct) { var NewTarget = _getPrototypeOf(this).constructor; result = Reflect.construct(Super, arguments, NewTarget); } else { result = Super.apply(this, arguments); } return _possibleConstructorReturn(this, result); }; }

function _possibleConstructorReturn(self, call) { if (call && (_typeof(call) === "object" || typeof call === "function")) { return call; } return _assertThisInitialized(self); }

function _assertThisInitialized(self) { if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }

function _isNativeReflectConstruct() { if (typeof Reflect === "undefined" || !Reflect.construct) return false; if (Reflect.construct.sham) return false; if (typeof Proxy === "function") return true; try { Boolean.prototype.valueOf.call(Reflect.construct(Boolean, [], function () {})); return true; } catch (e) { return false; } }

function _getPrototypeOf(o) { _getPrototypeOf = Object.setPrototypeOf ? Object.getPrototypeOf : function _getPrototypeOf(o) { return o.__proto__ || Object.getPrototypeOf(o); }; return _getPrototypeOf(o); }

function _defineProperty(obj, key, value) { if (key in obj) { Object.defineProperty(obj, key, { value: value, enumerable: true, configurable: true, writable: true }); } else { obj[key] = value; } return obj; }

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

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

var CHUNK_SIZE = 1024;

var XhrFileReader = /*#__PURE__*/function (_MediaFileReader) {
  _inherits(XhrFileReader, _MediaFileReader);

  var _super = _createSuper(XhrFileReader);

  function XhrFileReader(url) {
    var _this;

    _classCallCheck(this, XhrFileReader);

    _this = _super.call(this);

    _defineProperty(_assertThisInitialized(_this), "_url", void 0);

    _defineProperty(_assertThisInitialized(_this), "_fileData", void 0);

    _this._url = url;
    _this._fileData = new ChunkedFileData();
    return _this;
  }

  _createClass(XhrFileReader, [{
    key: "_init",
    value: function _init(callbacks) {
      if (XhrFileReader._config.avoidHeadRequests) {
        this._fetchSizeWithGetRequest(callbacks);
      } else {
        this._fetchSizeWithHeadRequest(callbacks);
      }
    }
  }, {
    key: "_fetchSizeWithHeadRequest",
    value: function _fetchSizeWithHeadRequest(callbacks) {
      var self = this;

      this._makeXHRRequest("HEAD", null, {
        onSuccess: function onSuccess(xhr) {
          var contentLength = self._parseContentLength(xhr);

          if (contentLength) {
            self._size = contentLength;
            callbacks.onSuccess();
          } else {
            // Content-Length not provided by the server, fallback to
            // GET requests.
            self._fetchSizeWithGetRequest(callbacks);
          }
        },
        onError: callbacks.onError
      });
    }
  }, {
    key: "_fetchSizeWithGetRequest",
    value: function _fetchSizeWithGetRequest(callbacks) {
      var self = this;

      var range = this._roundRangeToChunkMultiple([0, 0]);

      this._makeXHRRequest("GET", range, {
        onSuccess: function onSuccess(xhr) {
          var contentRange = self._parseContentRange(xhr);

          var data = self._getXhrResponseContent(xhr);

          if (contentRange) {
            if (contentRange.instanceLength == null) {
              // Last resort, server is not able to tell us the content length,
              // need to fetch entire file then.
              self._fetchEntireFile(callbacks);

              return;
            }

            self._size = contentRange.instanceLength;
          } else {
            // Range request not supported, we got the entire file
            self._size = data.length;
          }

          self._fileData.addData(0, data);

          callbacks.onSuccess();
        },
        onError: callbacks.onError
      });
    }
  }, {
    key: "_fetchEntireFile",
    value: function _fetchEntireFile(callbacks) {
      var self = this;

      this._makeXHRRequest("GET", null, {
        onSuccess: function onSuccess(xhr) {
          var data = self._getXhrResponseContent(xhr);

          self._size = data.length;

          self._fileData.addData(0, data);

          callbacks.onSuccess();
        },
        onError: callbacks.onError
      });
    }
  }, {
    key: "_getXhrResponseContent",
    value: function _getXhrResponseContent(xhr) {
      return xhr.responseBody || xhr.responseText || "";
    }
  }, {
    key: "_parseContentLength",
    value: function _parseContentLength(xhr) {
      var contentLength = this._getResponseHeader(xhr, "Content-Length");

      if (contentLength == null) {
        return contentLength;
      } else {
        return parseInt(contentLength, 10);
      }
    }
  }, {
    key: "_parseContentRange",
    value: function _parseContentRange(xhr) {
      var contentRange = this._getResponseHeader(xhr, "Content-Range");

      if (contentRange) {
        var parsedContentRange = contentRange.match(/bytes (\d+)-(\d+)\/(?:(\d+)|\*)/i);

        if (!parsedContentRange) {
          throw new Error("FIXME: Unknown Content-Range syntax: " + contentRange);
        }

        return {
          firstBytePosition: parseInt(parsedContentRange[1], 10),
          lastBytePosition: parseInt(parsedContentRange[2], 10),
          instanceLength: parsedContentRange[3] ? parseInt(parsedContentRange[3], 10) : null
        };
      } else {
        return null;
      }
    }
  }, {
    key: "loadRange",
    value: function loadRange(range, callbacks) {
      var self = this;

      if (self._fileData.hasDataRange(range[0], Math.min(self._size, range[1]))) {
        setTimeout(callbacks.onSuccess, 1);
        return;
      } // Always download in multiples of CHUNK_SIZE. If we're going to make a
      // request might as well get a chunk that makes sense. The big cost is
      // establishing the connection so getting 10bytes or 1K doesn't really
      // make a difference.


      range = this._roundRangeToChunkMultiple(range); // Upper range should not be greater than max file size

      range[1] = Math.min(self._size, range[1]);

      this._makeXHRRequest("GET", range, {
        onSuccess: function onSuccess(xhr) {
          var data = self._getXhrResponseContent(xhr);

          self._fileData.addData(range[0], data);

          callbacks.onSuccess();
        },
        onError: callbacks.onError
      });
    }
  }, {
    key: "_roundRangeToChunkMultiple",
    value: function _roundRangeToChunkMultiple(range) {
      var length = range[1] - range[0] + 1;
      var newLength = Math.ceil(length / CHUNK_SIZE) * CHUNK_SIZE;
      return [range[0], range[0] + newLength - 1];
    }
  }, {
    key: "_makeXHRRequest",
    value: function _makeXHRRequest(method, range, callbacks) {
      var xhr = this._createXHRObject();

      xhr.open(method, this._url);

      var onXHRLoad = function onXHRLoad() {
        // 200 - OK
        // 206 - Partial Content
        // $FlowIssue - xhr will not be null here
        if (xhr.status === 200 || xhr.status === 206) {
          callbacks.onSuccess(xhr);
        } else if (callbacks.onError) {
          callbacks.onError({
            "type": "xhr",
            "info": "Unexpected HTTP status " + xhr.status + ".",
            "xhr": xhr
          });
        }

        xhr = null;
      };

      if (typeof xhr.onload !== 'undefined') {
        xhr.onload = onXHRLoad;

        xhr.onerror = function () {
          if (callbacks.onError) {
            callbacks.onError({
              "type": "xhr",
              "info": "Generic XHR error, check xhr object.",
              "xhr": xhr
            });
          }
        };
      } else {
        xhr.onreadystatechange = function () {
          // $FlowIssue - xhr will not be null here
          if (xhr.readyState === 4) {
            onXHRLoad();
          }
        };
      }

      if (XhrFileReader._config.timeoutInSec) {
        xhr.timeout = XhrFileReader._config.timeoutInSec * 1000;

        xhr.ontimeout = function () {
          if (callbacks.onError) {
            callbacks.onError({
              "type": "xhr",
              // $FlowIssue - xhr.timeout will not be null
              "info": "Timeout after " + xhr.timeout / 1000 + "s. Use jsmediatags.Config.setXhrTimeout to override.",
              "xhr": xhr
            });
          }
        };
      }

      xhr.overrideMimeType("text/plain; charset=x-user-defined");

      if (range) {
        this._setRequestHeader(xhr, "Range", "bytes=" + range[0] + "-" + range[1]);
      }

      this._setRequestHeader(xhr, "If-Modified-Since", "Sat, 01 Jan 1970 00:00:00 GMT");

      xhr.send(null);
    }
  }, {
    key: "_setRequestHeader",
    value: function _setRequestHeader(xhr, headerName, headerValue) {
      if (XhrFileReader._config.disallowedXhrHeaders.indexOf(headerName.toLowerCase()) < 0) {
        xhr.setRequestHeader(headerName, headerValue);
      }
    }
  }, {
    key: "_hasResponseHeader",
    value: function _hasResponseHeader(xhr, headerName) {
      var allResponseHeaders = xhr.getAllResponseHeaders();

      if (!allResponseHeaders) {
        return false;
      }

      var headers = allResponseHeaders.split("\r\n");
      var headerNames = [];

      for (var i = 0; i < headers.length; i++) {
        headerNames[i] = headers[i].split(":")[0].toLowerCase();
      }

      return headerNames.indexOf(headerName.toLowerCase()) >= 0;
    }
  }, {
    key: "_getResponseHeader",
    value: function _getResponseHeader(xhr, headerName) {
      if (!this._hasResponseHeader(xhr, headerName)) {
        return null;
      }

      return xhr.getResponseHeader(headerName);
    }
  }, {
    key: "getByteAt",
    value: function getByteAt(offset) {
      var character = this._fileData.getByteAt(offset);

      return character.charCodeAt(0) & 0xff;
    }
  }, {
    key: "_isWebWorker",
    value: function _isWebWorker() {
      return typeof WorkerGlobalScope !== 'undefined' && self instanceof WorkerGlobalScope;
    }
  }, {
    key: "_createXHRObject",
    value: function _createXHRObject() {
      if (typeof window === "undefined" && !this._isWebWorker()) {
        // $FlowIssue - flow is not able to recognize this module.
        return new (require("xhr2").XMLHttpRequest)();
      }

      if (typeof XMLHttpRequest !== "undefined") {
        return new XMLHttpRequest();
      }

      throw new Error("XMLHttpRequest is not supported");
    }
  }], [{
    key: "canReadFile",
    value: function canReadFile(file) {
      return typeof file === 'string' && /^[a-z]+:\/\//i.test(file);
    }
  }, {
    key: "setConfig",
    value: function setConfig(config) {
      for (var key in config) {
        if (config.hasOwnProperty(key)) {
          this._config[key] = config[key];
        }
      }

      var disallowedXhrHeaders = this._config.disallowedXhrHeaders;

      for (var i = 0; i < disallowedXhrHeaders.length; i++) {
        disallowedXhrHeaders[i] = disallowedXhrHeaders[i].toLowerCase();
      }
    }
  }]);

  return XhrFileReader;
}(MediaFileReader);

_defineProperty(XhrFileReader, "_config", void 0);

XhrFileReader._config = {
  avoidHeadRequests: false,
  disallowedXhrHeaders: [],
  timeoutInSec: 30
};
module.exports = XhrFileReader;