Support basic authentication URL schema

[DrChat]

URL basic authentication is used by us to pass in PAT credentials for Azure DevOps, so it'd be nice to see it implemented here so we can look at using this crate :)

Notably, symchk does not support this, so this feature is super useful.

Reference: https://github.com/microsoft/pdblister/blob/88c9f0dd4075be7adfbfdac0505dba2d63be068d/crates/symsrv/src/nonblocking.rs#L235-L253 Note that I'm pretty sure I implemented this incorrectly - the token should be base64("<user>:<password>") instead of what I had there.

[mstange]

I think you can even just use reqwest::Client::builder().basic_auth("", Some(token)) and have reqwest do the base64-ification for you.

Edit Feb 17, 2024: Er, basic_auth is a method on the RequestBuilder, not on the ClientBuilder, and it accepts user+password, not a token. RequestBuilder::bearer_auth is the one that accepts a token.

[DrChat]

Ah - unfortunately only a thing for building requests, not a client. That may be a better design choice on their end though.

[mstange]

Oh right. Yes I agree, you'd want it per request, because your symbol path may contain multiple URLs.

[DrChat]

So, looking at this a bit more: Some symbol servers use bearer token authentication, and basic authentication won't cover these scenarios.

Expanding the symsrv string format to cover this could be a solution, but:

1) There is currently no URL schema for encoding a bearer token into a URL (such as described here). 2) Bearer tokens usually have a short expiration time, so this will only work for a short-term use of SymbolCache.

Other potential solutions to think about:

• Expose a "token provider" callback? This could be used to resolve tokens on-demand and ensure that the access token is always valid.
  • We could provide a "default" token provider that calls a command to fetch a new access token. This would work with tools like AzureAuth and end-users could directly provide a command.