pdfjs-dist/lib/display/fetch_stream.js

/**
 * @licstart The following is the entire license notice for the
 * Javascript code in this page
 *
 * Copyright 2019 Mozilla Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * @licend The above is the entire license notice for the
 * Javascript code in this page
 */
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.PDFFetchStream = void 0;

var _regenerator = _interopRequireDefault(require("@babel/runtime/regenerator"));

var _util = require("../shared/util");

var _network_utils = require("./network_utils");

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

function asyncGeneratorStep(gen, resolve, reject, _next, _throw, key, arg) { try { var info = gen[key](arg); var value = info.value; } catch (error) { reject(error); return; } if (info.done) { resolve(value); } else { Promise.resolve(value).then(_next, _throw); } }

function _asyncToGenerator(fn) { return function () { var self = this, args = arguments; return new Promise(function (resolve, reject) { var gen = fn.apply(self, args); function _next(value) { asyncGeneratorStep(gen, resolve, reject, _next, _throw, "next", value); } function _throw(err) { asyncGeneratorStep(gen, resolve, reject, _next, _throw, "throw", err); } _next(undefined); }); }; }

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 createFetchOptions(headers, withCredentials, abortController) {
  return {
    method: 'GET',
    headers: headers,
    signal: abortController && abortController.signal,
    mode: 'cors',
    credentials: withCredentials ? 'include' : 'same-origin',
    redirect: 'follow'
  };
}

var PDFFetchStream =
/*#__PURE__*/
function () {
  function PDFFetchStream(source) {
    _classCallCheck(this, PDFFetchStream);

    this.source = source;
    this.isHttp = /^https?:/i.test(source.url);
    this.httpHeaders = this.isHttp && source.httpHeaders || {};
    this._fullRequestReader = null;
    this._rangeRequestReaders = [];
  }

  _createClass(PDFFetchStream, [{
    key: "getFullReader",
    value: function getFullReader() {
      (0, _util.assert)(!this._fullRequestReader);
      this._fullRequestReader = new PDFFetchStreamReader(this);
      return this._fullRequestReader;
    }
  }, {
    key: "getRangeReader",
    value: function getRangeReader(begin, end) {
      if (end <= this._progressiveDataLength) {
        return null;
      }

      var reader = new PDFFetchStreamRangeReader(this, begin, end);

      this._rangeRequestReaders.push(reader);

      return reader;
    }
  }, {
    key: "cancelAllRequests",
    value: function cancelAllRequests(reason) {
      if (this._fullRequestReader) {
        this._fullRequestReader.cancel(reason);
      }

      var readers = this._rangeRequestReaders.slice(0);

      readers.forEach(function (reader) {
        reader.cancel(reason);
      });
    }
  }, {
    key: "_progressiveDataLength",
    get: function get() {
      return this._fullRequestReader ? this._fullRequestReader._loaded : 0;
    }
  }]);

  return PDFFetchStream;
}();

exports.PDFFetchStream = PDFFetchStream;

var PDFFetchStreamReader =
/*#__PURE__*/
function () {
  function PDFFetchStreamReader(stream) {
    var _this = this;

    _classCallCheck(this, PDFFetchStreamReader);

    this._stream = stream;
    this._reader = null;
    this._loaded = 0;
    this._filename = null;
    var source = stream.source;
    this._withCredentials = source.withCredentials || false;
    this._contentLength = source.length;
    this._headersCapability = (0, _util.createPromiseCapability)();
    this._disableRange = source.disableRange || false;
    this._rangeChunkSize = source.rangeChunkSize;

    if (!this._rangeChunkSize && !this._disableRange) {
      this._disableRange = true;
    }

    if (typeof AbortController !== 'undefined') {
      this._abortController = new AbortController();
    }

    this._isStreamingSupported = !source.disableStream;
    this._isRangeSupported = !source.disableRange;
    this._headers = new Headers();

    for (var property in this._stream.httpHeaders) {
      var value = this._stream.httpHeaders[property];

      if (typeof value === 'undefined') {
        continue;
      }

      this._headers.append(property, value);
    }

    var url = source.url;
    fetch(url, createFetchOptions(this._headers, this._withCredentials, this._abortController)).then(function (response) {
      if (!(0, _network_utils.validateResponseStatus)(response.status)) {
        throw (0, _network_utils.createResponseStatusError)(response.status, url);
      }

      _this._reader = response.body.getReader();

      _this._headersCapability.resolve();

      var getResponseHeader = function getResponseHeader(name) {
        return response.headers.get(name);
      };

      var _validateRangeRequest = (0, _network_utils.validateRangeRequestCapabilities)({
        getResponseHeader: getResponseHeader,
        isHttp: _this._stream.isHttp,
        rangeChunkSize: _this._rangeChunkSize,
        disableRange: _this._disableRange
      }),
          allowRangeRequests = _validateRangeRequest.allowRangeRequests,
          suggestedLength = _validateRangeRequest.suggestedLength;

      _this._isRangeSupported = allowRangeRequests;
      _this._contentLength = suggestedLength || _this._contentLength;
      _this._filename = (0, _network_utils.extractFilenameFromHeader)(getResponseHeader);

      if (!_this._isStreamingSupported && _this._isRangeSupported) {
        _this.cancel(new _util.AbortException('Streaming is disabled.'));
      }
    })["catch"](this._headersCapability.reject);
    this.onProgress = null;
  }

  _createClass(PDFFetchStreamReader, [{
    key: "read",
    value: function () {
      var _read = _asyncToGenerator(
      /*#__PURE__*/
      _regenerator["default"].mark(function _callee() {
        var _ref, value, done, buffer;

        return _regenerator["default"].wrap(function _callee$(_context) {
          while (1) {
            switch (_context.prev = _context.next) {
              case 0:
                _context.next = 2;
                return this._headersCapability.promise;

              case 2:
                _context.next = 4;
                return this._reader.read();

              case 4:
                _ref = _context.sent;
                value = _ref.value;
                done = _ref.done;

                if (!done) {
                  _context.next = 9;
                  break;
                }

                return _context.abrupt("return", {
                  value: value,
                  done: done
                });

              case 9:
                this._loaded += value.byteLength;

                if (this.onProgress) {
                  this.onProgress({
                    loaded: this._loaded,
                    total: this._contentLength
                  });
                }

                buffer = new Uint8Array(value).buffer;
                return _context.abrupt("return", {
                  value: buffer,
                  done: false
                });

              case 13:
              case "end":
                return _context.stop();
            }
          }
        }, _callee, this);
      }));

      function read() {
        return _read.apply(this, arguments);
      }

      return read;
    }()
  }, {
    key: "cancel",
    value: function cancel(reason) {
      if (this._reader) {
        this._reader.cancel(reason);
      }

      if (this._abortController) {
        this._abortController.abort();
      }
    }
  }, {
    key: "headersReady",
    get: function get() {
      return this._headersCapability.promise;
    }
  }, {
    key: "filename",
    get: function get() {
      return this._filename;
    }
  }, {
    key: "contentLength",
    get: function get() {
      return this._contentLength;
    }
  }, {
    key: "isRangeSupported",
    get: function get() {
      return this._isRangeSupported;
    }
  }, {
    key: "isStreamingSupported",
    get: function get() {
      return this._isStreamingSupported;
    }
  }]);

  return PDFFetchStreamReader;
}();

var PDFFetchStreamRangeReader =
/*#__PURE__*/
function () {
  function PDFFetchStreamRangeReader(stream, begin, end) {
    var _this2 = this;

    _classCallCheck(this, PDFFetchStreamRangeReader);

    this._stream = stream;
    this._reader = null;
    this._loaded = 0;
    var source = stream.source;
    this._withCredentials = source.withCredentials || false;
    this._readCapability = (0, _util.createPromiseCapability)();
    this._isStreamingSupported = !source.disableStream;

    if (typeof AbortController !== 'undefined') {
      this._abortController = new AbortController();
    }

    this._headers = new Headers();

    for (var property in this._stream.httpHeaders) {
      var value = this._stream.httpHeaders[property];

      if (typeof value === 'undefined') {
        continue;
      }

      this._headers.append(property, value);
    }

    this._headers.append('Range', "bytes=".concat(begin, "-").concat(end - 1));

    var url = source.url;
    fetch(url, createFetchOptions(this._headers, this._withCredentials, this._abortController)).then(function (response) {
      if (!(0, _network_utils.validateResponseStatus)(response.status)) {
        throw (0, _network_utils.createResponseStatusError)(response.status, url);
      }

      _this2._readCapability.resolve();

      _this2._reader = response.body.getReader();
    });
    this.onProgress = null;
  }

  _createClass(PDFFetchStreamRangeReader, [{
    key: "read",
    value: function () {
      var _read2 = _asyncToGenerator(
      /*#__PURE__*/
      _regenerator["default"].mark(function _callee2() {
        var _ref2, value, done, buffer;

        return _regenerator["default"].wrap(function _callee2$(_context2) {
          while (1) {
            switch (_context2.prev = _context2.next) {
              case 0:
                _context2.next = 2;
                return this._readCapability.promise;

              case 2:
                _context2.next = 4;
                return this._reader.read();

              case 4:
                _ref2 = _context2.sent;
                value = _ref2.value;
                done = _ref2.done;

                if (!done) {
                  _context2.next = 9;
                  break;
                }

                return _context2.abrupt("return", {
                  value: value,
                  done: done
                });

              case 9:
                this._loaded += value.byteLength;

                if (this.onProgress) {
                  this.onProgress({
                    loaded: this._loaded
                  });
                }

                buffer = new Uint8Array(value).buffer;
                return _context2.abrupt("return", {
                  value: buffer,
                  done: false
                });

              case 13:
              case "end":
                return _context2.stop();
            }
          }
        }, _callee2, this);
      }));

      function read() {
        return _read2.apply(this, arguments);
      }

      return read;
    }()
  }, {
    key: "cancel",
    value: function cancel(reason) {
      if (this._reader) {
        this._reader.cancel(reason);
      }

      if (this._abortController) {
        this._abortController.abort();
      }
    }
  }, {
    key: "isStreamingSupported",
    get: function get() {
      return this._isStreamingSupported;
    }
  }]);

  return PDFFetchStreamRangeReader;
}();