Promiseallfetchurl1

Promiseallfetchurl1 is a JavaScript utility pattern used to perform multiple HTTP requests in parallel and aggregate their results using Promise.all. The pattern centers on starting with a primary URL, referred to as URL1, and optionally issuing additional fetch calls concurrently. In codebases, a helper named promiseallfetchurl1 may encapsulate this workflow to streamline data fetching.

How it works: The function creates an array of fetch promises for URL1 and any extra endpoints, then passes that array to Promise.all. When all promises resolve, it processes the responses (for example, by calling response.json()) and returns an array of results. This approach reduces total latency compared to sequential fetches and consolidates error handling, though a single failing request can cause the entire promise to reject unless individual error handling is applied.

Example usage:

async function promiseallfetchurl1(url1, extraUrls = []) {

const requests = [fetch(url1), ...extraUrls.map(u => fetch(u))];

const responses = await Promise.all(requests);

return Promise.all(responses.map(r => (r.ok ? r.json() : Promise.reject(new Error(r.statusText)))));

}

Alternative patterns include using Promise.allSettled for partial success handling or wrapping each fetch in its own try/catch to provide per-request resilience. The promiseallfetchurl1 pattern is commonly used in client-side web applications where multiple data sources must be retrieved quickly and then combined for rendering.

Limitations and considerations: It assumes endpoints return JSON (or the code is adapted for other formats). It propagates the first rejection by default; for more granular control, consider Promise.allSettled or custom per-request error handling. See also Promise.all and fetch in asynchronous JavaScript.