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- /*
- Copyright 2017 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
-
- https://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.
- */
-
- import {WorkboxError} from 'workbox-core/_private/WorkboxError.mjs';
- import {assert} from 'workbox-core/_private/assert.mjs';
- import {logger} from 'workbox-core/_private/logger.mjs';
-
- import {calculateEffectiveBoundaries} from
- './utils/calculateEffectiveBoundaries.mjs';
- import {parseRangeHeader} from './utils/parseRangeHeader.mjs';
-
- import './_version.mjs';
-
- /**
- * Given a `Request` and `Response` objects as input, this will return a
- * promise for a new `Response`.
- *
- * @param {Request} request A request, which should contain a Range:
- * header.
- * @param {Response} originalResponse An original response containing the full
- * content.
- * @return {Promise<Response>} Either a `206 Partial Content` response, with
- * the response body set to the slice of content specified by the request's
- * `Range:` header, or a `416 Range Not Satisfiable` response if the
- * conditions of the `Range:` header can't be met.
- *
- * @memberof workbox.rangeRequests
- */
- async function createPartialResponse(request, originalResponse) {
- try {
- if (process.env.NODE_ENV !== 'production') {
- assert.isInstance(request, Request, {
- moduleName: 'workbox-range-requests',
- funcName: 'createPartialResponse',
- paramName: 'request',
- });
-
- assert.isInstance(originalResponse, Response, {
- moduleName: 'workbox-range-requests',
- funcName: 'createPartialResponse',
- paramName: 'originalResponse',
- });
- }
-
- const rangeHeader = request.headers.get('range');
- if (!rangeHeader) {
- throw new WorkboxError('no-range-header');
- }
-
- const boundaries = parseRangeHeader(rangeHeader);
- const originalBlob = await originalResponse.blob();
-
- const effectiveBoundaries = calculateEffectiveBoundaries(
- originalBlob, boundaries.start, boundaries.end);
-
- const slicedBlob = originalBlob.slice(effectiveBoundaries.start,
- effectiveBoundaries.end);
- const slicedBlobSize = slicedBlob.size;
-
- const slicedResponse = new Response(slicedBlob, {
- // Status code 206 is for a Partial Content response.
- // See https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/206
- status: 206,
- statusText: 'Partial Content',
- headers: originalResponse.headers,
- });
-
- slicedResponse.headers.set('Content-Length', slicedBlobSize);
- slicedResponse.headers.set('Content-Range',
- `bytes ${effectiveBoundaries.start}-${effectiveBoundaries.end - 1}/` +
- originalBlob.size);
-
- return slicedResponse;
- } catch (error) {
- if (process.env.NODE_ENV !== 'production') {
- logger.warn(`Unable to construct a partial response; returning a ` +
- `416 Range Not Satisfiable response instead.`);
- logger.groupCollapsed(`View details here.`);
- logger.unprefixed.log(error);
- logger.unprefixed.log(request);
- logger.unprefixed.log(originalResponse);
- logger.groupEnd();
- }
-
- return new Response('', {
- status: 416,
- statusText: 'Range Not Satisfiable',
- });
- }
- }
-
- export {createPartialResponse};
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