knock

Intercept, modify, or pause fetch/XHR in any page. Rule-based response overrides, cookie injection, and in-page live editing.

knock — drive the browser directly from Chrome DevTools 📖 Docs, screenshots, live demos: https://knock.racgoo.com A DevTools panel that drives the browser end-to-end. Intercept every fetch and XMLHttpRequest, rewrite them on the fly with rule pipelines, or pause a request and hand-edit it in a floating in-page editor. Record click / fill / submit flows and replay them deterministically — then run the very same recordings headless in CI with knock-cli. All from one panel, with no test code to write. Runs entirely in your browser. No account, no telemetry, no server. INTERCEPT & MOCK — Capture every fetch / XHR with method, URL, status, headers, body. The detail pane shows the post-modify state, and a DevTools-style filter bar (method:POST status:5xx -url:analytics) keeps the stream readable. — Rule pipelines rewrite outgoing requests (headers / query / body / cookies — Override or Replace) and synthesize responses (status / headers / body / delay / Set-Cookies). Rules run in order: earlier rules transform first, later rules see their output. — Pause either side of a request and edit it live in a draggable in-page editor before letting it through. — Real cookies through chrome.cookies — actual jar state, not a fake header. — Rule Sets bundle rules with domain allowlists. Export / import as JSON. RECORD & REPLAY — Record click / fill / submit / change / navigate flows in the Automation tab, drop in expect assertions, and replay deterministically against the captured network — or fire live against the real backend for auto-login / repeat-task helpers. — Replay Storage re-plants the recording's cookies + localStorage + sessionStorage before each run, so logged-in flows replay logged-in. The recorded viewport is restored too. — Secret fields (passwords, tokens) are masked in the panel and logs, and the export dialog warns before a recording carrying real credentials leaves your machine. RUN IN CI — knock-cli (on npm) — npx knock-cli ./tests replays the exact same recordings headless. Not a port: knock-cli bundles the extension's actual replay engine, so a recording that passes in the panel passes in CI — same selectors, same network + storage replay. — Built for pipelines: exit code 0/1/2, parallel workers across test sets, Chromium / Firefox / WebKit, and a config file that can spawn your dev server before the run. — npx knock-cli serve connects the panel to a folder in your repo — record in the browser, and every recording lands on disk as a reviewable JSON file. — Impact analysis: knock-cli impact api/users ./tests lists which recordings touch an API you're about to change — before you break them. → Get started: https://knock.racgoo.com/docs/getting-started