{
  "id": 9740497,
  "title": "A 200 OK can still belong to the wrong input",
  "url": "https://urgent.news/2026/09/25/a-200-ok-can-still-belong-to-the-wrong-input",
  "topic": "tech",
  "section": "Tech",
  "published": "2026-09-25T09:23:01.000Z",
  "source": {
    "name": "Dev.to",
    "slug": "dev-to",
    "url": "https://dev.to/civicdataforge/a-200-ok-can-still-belong-to-the-wrong-input-1o82"
  },
  "original_language": "en",
  "account": "Even a successful HTTP response, like a 200 OK status, can be invalid if the client input has changed since the request was sent. For instance, imagine a shipping quote where the customer swaps the destination from Boston to Seattle after the quote is already generated. The initial success message may appear trustworthy due to the green status, but it actually shows the wrong price for the new destination. The key is to give each form input a revision number, incrementing it whenever relevant input changes or a new request begins. Each request should only update the interface with its current revision. This way, only the revision associated with the current input can alter the displayed information. When editing the input, invalidate the previous state, restart the counter, abort any ongoing requests, and update the interface accordingly. The example provided demonstrates this concept in a framework-independent manner using JavaScript. A fetch promise may still resolve even for HTTP errors like a 404, so the adapter must reject such errors to prevent them from being rendered as successful results. This client-side consistency mechanism helps ensure that a stale success cannot replace a newer result or error, and that stale errors don't persist when the interface changes.",
  "summary": "A request succeeds. The JSON is valid. The interface shows the wrong result anyway. One way this happens has nothing to do with the server: Someone submits input A. While the request runs, they change the form to input B. A's response arrives and renders underneath B. The response is correct for the request. The screen is wrong for the current input. On a quote, eligibility check, or data lookup,…",
  "key_points": [
    "A 200 OK response may not reflect current client input",
    "Revision numbers needed for each form input",
    "Invalidate previous state when updating inputs"
  ],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}