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HTTPGlass Docs

What is HTTPGlass

HTTPGlass is an HTTP and HTTPS debugging proxy for macOS. It captures the requests your apps and command-line tools send and the responses they get back, decrypts HTTPS so you can read it, and gives you tools to filter, search, repeat, and — on Pro — change that traffic on its way through.

How it works

Section titled “How it works”
  • A local proxy. HTTPGlass runs a proxy inside the app, listening only on 127.0.0.1 (port 9191 unless that port is taken).
  • Your Mac’s proxy settings. While you capture, HTTPGlass points the HTTP and HTTPS proxy of each network service at that port, and puts the previous settings back when you stop or quit. See How capture works.
  • A root certificate made on your Mac. HTTPGlass generates its own root certificate the first time it needs one and, once you’ve trusted it, signs a certificate for each site it reads. The private key never leaves your Mac. See Root certificate.
  • The app behind each request. HTTPGlass works out which process opened each connection and rolls helper processes up to their app, so a request from Chrome’s network helper shows as Chrome and a request from curl shows as curl.

Nothing is sent to a separate machine. Captured traffic, the certificate’s private key, and your rules stay in ~/Library/Application Support/HTTPGlass.

App-first

Section titled “App-first”

Most proxies ask you to decide which hosts to decrypt. HTTPGlass starts from the question you arrived with: which app are you debugging? Pick it, and HTTPGlass decrypts everything that app sends, on every host, and shows only its traffic. See Pick the app you’re debugging.

What you can do with it

Section titled “What you can do with it”
  • Watch every request and response as it happens, by app, by domain, or all together
  • Read JSON, XML, HTML, form, cookie, image, and binary bodies with a viewer that fits each
  • Search across URLs, headers, and bodies
  • Copy a request as cURL, repeat it, or generate Swift, Python, JavaScript, or Kotlin from it
  • Export selected requests as a HAR file
  • Pause a request or response on a breakpoint and edit it before it continues
  • Block or allow matching hosts or paths, or force them uncached (No-Cache is Pro)
  • Serve a canned response instead of hitting the real backend (Pro)
  • Send matching requests to a staging server or a different path (Pro)
  • Rewrite headers, bodies, status codes, and query parameters automatically (Pro)
  • Run your own JavaScript against requests and responses (Pro)
  • Throttle connections to 3G, GPRS, or custom bandwidth and latency (Pro)

Next

Section titled “Next”