Dynamic WPAD file

[svrooij]

Maybe it is a good idea to instead off proxy everything, the proxy itself would host a wpad file with just the defined hosts to point to the proxy.

That would mean the rest of the internet stays as fast as possible and just the intercepted hosts would even reach the proxy.

The url to this file, with special mime-type! Can then be set as auto discover proxy url.

[waldekmastykarz]

Interesting find. I wonder if it's worth the effort given that it's a dev tool that you typically start and stop while building your app rather than something you'd run the whole day in the background. It seems like configuring the system to use the wpad file isn't trivial (might be easier if we could automate it) and even then it works only on Windows.

It would be interesting to try it though and see if it helps us prevents issues with Azure Functions startup and Teams auth, but I suggest we POC that first before we integrate it in Dev Proxy itself.

[waldekmastykarz]

Thanks @svrooij for the idea! After researching WPAD, we concluded that the autodiscovery mechanism (DNS/DHCP setup) is too heavyweight for a dev tool — it's designed for enterprise network configuration, not local development.

That said, the underlying goal — only routing watched hosts through the proxy — is valuable. We've opened a new issue to explore serving a PAC (Proxy Auto-Config) file directly from Dev Proxy to achieve selective routing without the WPAD infrastructure. See #1531.