Differences between proxy client and node client

[madsteer]

I have my typescript UI working using @unleash/proxy-client-react1 FlagProvider. It calls off to my unleash proxy at http://localhost:3000/proxy. I want to check feature flags in a backend typescript app so I installed unleash-client there and am following the docs here. Where I'm getting confused is the node unleash.isEnabled() seems to be calling http://127.0.0.1:3000/proxy/client/features instead of, or in addition to, http://127.0.0.1:3000/proxy and I'm getting a 401 for my given client key

indeed, with curl I can auth to http://127.0.0.1:3000/proxy with a an auth header of Authorization: client-key but http://127.0.0.1:3000/proxy/client/features with that same auth header gets me a 401.

I'm unable to understand how I can configure an auth key for that client/features path and/or check to see if a feature is turned on in a way that does not call the http://127.0.0.1:3000/proxy/client/features url.

For context I'm running unleash proxy via Docker.

Thanks for any help

[daveleek]

Hello @madsteer and thank you for reaching out!

The first thing to check is that you're using different API token types for these two SDKs.

The @unleash/proxy-client-react SDK is a frontend SDK (doesn't do its evaluations locally, fetches already resolved features from a proxy/frontend API) and uses a frontend API token. Seems like you have this working.
The unleash-client SDK is a backend SDK, and requires a backend API token to do its job. This SDK does do its evaluations locally according to the flag configuration that it needs to collect from the /client/features endpoint.

The proxy serves both of these purposes, but needs to be provided the correct token type for the corresponding API

[madsteer]

so if I'm running the unleash-proxy via Docker, I would need to have a UNLEASH_PROXY_CLIENT_KEYS=client-token and a UNLEASH_API_TOKEN=api-token?

if I do that:
curl -v -H 'Authorization: client-token' http://localhost:3000/proxy is working, but
curl -v -H 'Authorization: api-token' http://localhost:3000/proxy/client/features is still erroring with a 401, so I'm still missing something I guess. Either UNLEASH_API_TOKEN is the wrong environment variable or I'm still missing something about the backend API token

thanks,

[madsteer]

I think I figured out my confusion/mistake. I think I need to be using the unleash-proxy-client module for my backend code, not the unleash-client. Correct me if I"m wrong, but I think curl -v -H 'Authorization: client-token' http://localhost:3000/proxy will cover that module as well as @unleash/proxy-client-react, yes?

[gastonfournier]

There's also some documentation here: https://docs.getunleash.io/understanding-unleash/unleash-overview#unleash-apis