Is there an equivalent to bazels `--remote_header`

[MarshallOfSound]

Looking at using an RBE cluster that you authenticate to via a custom header x-foo-bar=my-key, it's not super clear how auth currently works in reclient but it doesn't look like there is an equivalent for this bazel flag.

Could someone either tell me I'm wrong 😆 or point me in the right direction of the code I could implement this in? Auth feels quite splayed, I see references to external tokens but not sure how that's wired in

[Yannic]

IIUC, you can use --credential_file to specify a path to a JSON file with credentials to provide arbitrary headers.

We are also working on improving authentication for reclient similar to what Bazel supports :)

[MarshallOfSound]

@Yannic It looks like credential_file expects some kind of JWT for GCP 🤔

couldn't create RPC creds for https://www.googleapis.com/auth/cloud-platform: couldn't create RPC creds from creds: google: read JWT from JSON credentials: 'type' field is "" (expected "service_account"), authentication type (identity) used="credentials file"

I don't see a non-GCP based auth option rn, even scanned the code a bit, the external token flag doesn't appear to be wired up

[gkousik]

I think this issue and the discussion we are having in bazelbuild/remote-apis-sdks#507 are related. I'll update here when we flush out an interface for how the credentials helper is going to look like.

[raphael10-collab]

I opened a related-issue here: #11

Looking forward to an example of credental_file, for a self-hosted buildbarn remote instance to work

[banikharbanda]

Closing this out since it's being tracked in #11