You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
120 lines
4.5 KiB
120 lines
4.5 KiB
/* |
|
Copyright 2018 Google LLC |
|
|
|
Use of this source code is governed by an MIT-style |
|
license that can be found in the LICENSE file or at |
|
https://opensource.org/licenses/MIT. |
|
*/ |
|
import { assert } from 'workbox-core/_private/assert.js'; |
|
import { Deferred } from 'workbox-core/_private/Deferred.js'; |
|
import { logger } from 'workbox-core/_private/logger.js'; |
|
import { WorkboxError } from 'workbox-core/_private/WorkboxError.js'; |
|
import './_version.js'; |
|
/** |
|
* Takes either a Response, a ReadableStream, or a |
|
* [BodyInit](https://fetch.spec.whatwg.org/#bodyinit) and returns the |
|
* ReadableStreamReader object associated with it. |
|
* |
|
* @param {workbox-streams.StreamSource} source |
|
* @return {ReadableStreamReader} |
|
* @private |
|
*/ |
|
function _getReaderFromSource(source) { |
|
if (source instanceof Response) { |
|
// See https://github.com/GoogleChrome/workbox/issues/2998 |
|
if (source.body) { |
|
return source.body.getReader(); |
|
} |
|
throw new WorkboxError('opaque-streams-source', { type: source.type }); |
|
} |
|
if (source instanceof ReadableStream) { |
|
return source.getReader(); |
|
} |
|
return new Response(source).body.getReader(); |
|
} |
|
/** |
|
* Takes multiple source Promises, each of which could resolve to a Response, a |
|
* ReadableStream, or a [BodyInit](https://fetch.spec.whatwg.org/#bodyinit). |
|
* |
|
* Returns an object exposing a ReadableStream with each individual stream's |
|
* data returned in sequence, along with a Promise which signals when the |
|
* stream is finished (useful for passing to a FetchEvent's waitUntil()). |
|
* |
|
* @param {Array<Promise<workbox-streams.StreamSource>>} sourcePromises |
|
* @return {Object<{done: Promise, stream: ReadableStream}>} |
|
* |
|
* @memberof workbox-streams |
|
*/ |
|
function concatenate(sourcePromises) { |
|
if (process.env.NODE_ENV !== 'production') { |
|
assert.isArray(sourcePromises, { |
|
moduleName: 'workbox-streams', |
|
funcName: 'concatenate', |
|
paramName: 'sourcePromises', |
|
}); |
|
} |
|
const readerPromises = sourcePromises.map((sourcePromise) => { |
|
return Promise.resolve(sourcePromise).then((source) => { |
|
return _getReaderFromSource(source); |
|
}); |
|
}); |
|
const streamDeferred = new Deferred(); |
|
let i = 0; |
|
const logMessages = []; |
|
const stream = new ReadableStream({ |
|
pull(controller) { |
|
return readerPromises[i] |
|
.then((reader) => reader.read()) |
|
.then((result) => { |
|
if (result.done) { |
|
if (process.env.NODE_ENV !== 'production') { |
|
logMessages.push([ |
|
'Reached the end of source:', |
|
sourcePromises[i], |
|
]); |
|
} |
|
i++; |
|
if (i >= readerPromises.length) { |
|
// Log all the messages in the group at once in a single group. |
|
if (process.env.NODE_ENV !== 'production') { |
|
logger.groupCollapsed(`Concatenating ${readerPromises.length} sources.`); |
|
for (const message of logMessages) { |
|
if (Array.isArray(message)) { |
|
logger.log(...message); |
|
} |
|
else { |
|
logger.log(message); |
|
} |
|
} |
|
logger.log('Finished reading all sources.'); |
|
logger.groupEnd(); |
|
} |
|
controller.close(); |
|
streamDeferred.resolve(); |
|
return; |
|
} |
|
// The `pull` method is defined because we're inside it. |
|
return this.pull(controller); |
|
} |
|
else { |
|
controller.enqueue(result.value); |
|
} |
|
}) |
|
.catch((error) => { |
|
if (process.env.NODE_ENV !== 'production') { |
|
logger.error('An error occurred:', error); |
|
} |
|
streamDeferred.reject(error); |
|
throw error; |
|
}); |
|
}, |
|
cancel() { |
|
if (process.env.NODE_ENV !== 'production') { |
|
logger.warn('The ReadableStream was cancelled.'); |
|
} |
|
streamDeferred.resolve(); |
|
}, |
|
}); |
|
return { done: streamDeferred.promise, stream }; |
|
} |
|
export { concatenate };
|
|
|