Yes, I'm pretty sure as I designed the proxy infrastrucuture
The way PAC file is in use like it's download the latest pac file from the predefined (Autoconfig) URL _if_ available. If not will use the latest cached version. So, in my example if the Proxy server holding the PAC file unavailable (eg the client is off-office network) the very last line of the PAC file take place which is:
// DEFAULT RULE: All other traffic, use below proxies, in fail-over order.
return "DIRECT";
So, the traffic will flow without any proxy server just like in a no-PAC file environment. (Btw if the machine is on the office network and can access the proxy server calibre still not able to connect to the internet, so it's _NOT_ a pac file access related issue)
Also using pac file is not a new thing, those kind of proxy config exists for many years so had plenty of time to develop this quite simple thing into calibre
Quote:
Originally Posted by davidfor
Are you sure about that for the PAC file usage? I would have expected that if the PAC file was not available, or the proxy it specified was not available, you wouldn't be able to access the URL using the client. If you were able to, it could be considered a security issue in a lot of corporate environments. I'm not sure on this as I've never set one up.
To use a PAC file, the client must:
- Have a way to configure the URL to retrieve the PAC file.
- Retrieve the PAC file.
- Each time the client wants to access a URL, it has to call the Javascript function in PAC file passing the URL and host name.
- Then interpret the results of the call to decide whether to access the URL directly or via the returned proxy.
- Handle when the proxy server is not available.
None of that is hard, but it takes time develop, test and maintain. And the client has to be able to execute Javascript. The latter makes PAC file support for most clients undesirable for most projects. With that, I can understand why Kovid doesn't want to support them.
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