javascript / expert
Snippet
Managing Concurrent Async Requests with AbortSignal in Custom Stores
When triggering multiple rapid asynchronous requests in Svelte custom stores, race conditions can cause stale data to overwrite recent updates. Utilizing AbortController cancels pending HTTP requests automatically whenever a new invocation occurs.
snippet.js
javascript
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export function createAsyncAbortStore() {let activeController = null;return {async executeFetch(requestUrl) {if (activeController) activeController.abort();activeController = new AbortController();const response = await fetch(requestUrl, { signal: activeController.signal });return await response.json();}};}
svelte
Breakdown
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export function createAsyncAbortStore() {
Factory function establishing a store pattern with request cancellation capabilities.
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let activeController = null;
Holds a reference to the active AbortController instance for current requests.
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if (activeController) activeController.abort();
Cancels any ongoing HTTP fetch operation before initiating a replacement request.
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activeController = new AbortController();
Instantiates a fresh AbortController instance for signal binding.
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const response = await fetch(requestUrl, { signal: activeController.signal });
Passes the cancellation signal option directly into the native fetch execution.