Source: lib/util/networking.js

/**
 * @license
 * Copyright 2016 Google Inc.
 *
 * 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.
 */
goog.provide('shaka.util.Networking');
/**
 * A collection of shared utilities that bridge the gap between our networking
 * code and the other parts of our code base. This is to allow
 * |shaka.net.NetworkingEngine| to remain general.
 *
 * @final
 */
shaka.util.Networking = class {
  /**
   * Create a request message for a segment. Providing |start| and |end|
   * will set the byte range. A non-zero start must be provided for |end| to
   * be used.
   *
   * @param {!Array.<string>} uris
   * @param {?number} start
   * @param {?number} end
   * @param {shaka.extern.RetryParameters} retryParameters
   * @return {shaka.extern.Request}
   */
  static createSegmentRequest(uris, start, end, retryParameters) {
    const request = shaka.net.NetworkingEngine.makeRequest(
        uris, retryParameters);
    if (start == 0 && end == null) {
      // This is a request for the entire segment.  The Range header is not
      // required.  Note that some web servers don't accept Range headers, so
      // don't set one if it's not strictly required.
    } else {
      if (end) {
        request.headers['Range'] = 'bytes=' + start + '-' + end;
      } else {
        request.headers['Range'] = 'bytes=' + start + '-';
      }
    }
    return request;
  }
};