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How to replay the requests of a browser's HAR file on your own service

Since app version 1.4.0

The ProximaClient inspector reads a HAR file a browser saved and turns its requests into ones ready to send: you can adjust any of them and send it to the service on your computer. That is how you repeat a bug a tester or a client caught in their browser.

How to save a HAR file in the browser​

  • Chrome: in the developer tools, on the Network tab, repeat the action with the bug and pick "Export HAR (sanitized)..." in the export menu. That file has no cookies and no Authorization header. The option with them, "Export HAR (with sensitive data)", appears after you turn on "Allow to generate HAR with sensitive data" in Settings → Preferences → Network (Chrome documentation).
  • Firefox: in the developer tools, on the Network tab, repeat the action with the bug and pick "Save All As HAR" in the request list's context menu (Firefox documentation).

A file with cookies and Authorization lets its reader into the account of whoever saved it. Send such a file only privately, delete it after use, and ask its author to sign out of the site. It's usually simpler to take a file without them and type a test account's header into the request before you send it.

HTTP Toolkit, Proxyman and the ProximaClient inspector itself save HAR files too.

How to send a request from the file​

  1. Open the "Requests" tab of the HTTPS tunnel whose service should get the request.
  2. Click the arrow on the "New request" button and pick "From HAR".
  3. Click "Choose file" and pick the HAR file. The inspector says how many requests it holds and lists them.
  4. Pick a request: its method, path, headers and body fill the window's fields without sending anything. Adjust them if you need to.
  5. Next to the request's path, leave "Direct" and click "Send": the request goes straight to the service on your computer.

Check: a new row with this request and your service's answer shows up in the log.

The file is not sent anywhere or kept, and sending from it is free on every plan. On Pro and Ultra, you can put the request into an inspector collection to replay it later: before sending, turn on "Save to a collection" in the window (it shows once a collection exists), and "Send and repeat N times…" on the "Send" button replays it many times at once.

What a file can't replay​

  • Requests that are not HTTP: WebSocket (ws:, wss:), inline data (data:, blob:), browser extensions' requests.
  • Requests whose body the browser did not save whole. Chrome leaves out the files of upload forms, and Firefox keeps only the first megabyte of a body.
  • Requests with a body over 8 MB.
  • Requests whose body is not text, for example an image.

The inspector reports how many requests it skipped and why. It doesn't open a file over 32 MB or with more than 1000 requests.