39 lines
1.0 KiB
JavaScript
39 lines
1.0 KiB
JavaScript
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/*
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Copyright 2018 Google LLC
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Use of this source code is governed by an MIT-style
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license that can be found in the LICENSE file or at
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https://opensource.org/licenses/MIT.
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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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