67 lines
1.8 KiB
JavaScript
67 lines
1.8 KiB
JavaScript
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/**
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* The AsyncQueue class used to sequentialize burst requests
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*/
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class AsyncQueue {
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constructor() {
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/**
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* The promises array
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*/
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Object.defineProperty(this, "promises", {
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enumerable: true,
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configurable: true,
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writable: true,
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value: []
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});
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}
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/**
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* The remaining amount of queued promises
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*/
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get remaining() {
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return this.promises.length;
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}
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/**
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* Waits for last promise and queues a new one
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* @example
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* ```typescript
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* const queue = new AsyncQueue();
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* async function request(url, options) {
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* await queue.wait();
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* try {
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* const result = await fetch(url, options);
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* // Do some operations with 'result'
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* } finally {
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* // Remove first entry from the queue and resolve for the next entry
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* queue.shift();
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* }
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* }
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*
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* request(someUrl1, someOptions1); // Will call fetch() immediately
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* request(someUrl2, someOptions2); // Will call fetch() after the first finished
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* request(someUrl3, someOptions3); // Will call fetch() after the second finished
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* ```
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*/
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wait() {
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const next = this.promises.length ? this.promises[this.promises.length - 1].promise : Promise.resolve();
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let resolve;
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const promise = new Promise((res) => {
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resolve = res;
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});
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this.promises.push({
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resolve: resolve,
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promise
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});
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return next;
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}
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/**
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* Frees the queue's lock for the next item to process
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*/
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shift() {
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const deferred = this.promises.shift();
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if (typeof deferred !== 'undefined')
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deferred.resolve();
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}
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}
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export { AsyncQueue };
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//# sourceMappingURL=index.mjs.map
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