46 lines
1.4 KiB
JavaScript
46 lines
1.4 KiB
JavaScript
/*
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Copyright 2018 Google Inc. All Rights Reserved.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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import './_version.mjs';
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let cachedIsSupported = undefined;
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/**
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* This is a utility method that determines whether the current browser supports
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* the features required to create streamed responses. Currently, it checks if
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* [`ReadableStream`](https://developer.mozilla.org/en-US/docs/Web/API/ReadableStream/ReadableStream)
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* can be created.
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*
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* @return {boolean} `true`, if the current browser meets the requirements for
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* streaming responses, and `false` otherwise.
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*
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* @memberof workbox.streams
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*/
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function isSupported() {
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if (cachedIsSupported === undefined) {
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// See https://github.com/GoogleChrome/workbox/issues/1473
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try {
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new ReadableStream({start() {}});
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cachedIsSupported = true;
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} catch (error) {
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cachedIsSupported = false;
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}
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}
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return cachedIsSupported;
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}
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export {isSupported};
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