StreamTokenProvider 5.1.1 API

```
public interface StreamTokenProvider

                    
```
Supplies authentication tokens (JWTs) for a given user.
Implementations usually call your backend to mint or fetch a signed, short-lived JWT for the provided user ID. Never embed server secrets or mint tokens on-device.
- Must return a valid, signed JWT for the requested userId.
- May be invoked multiple times (e.g., initial connect, refresh); implement caching if appropriate.
- This is a suspend function; perform network/IO work without blocking and respect cancellation.
- Signal failures by throwing an exception (don’t return empty/placeholder tokens).
```
class MyTokenProvider(
    private val authApi: AuthApi
) : StreamTokenProvider {
    override suspend fun loadToken(userId: String): StreamToken {
        // Network call to your service; may throw on failure
        val response = authApi.issueToken(userId)
        val streamToken = StreamToken.from(response.token)
        return streamToken
    }
}
```
- Token creation/rotation must happen on your server.
- Prefer short expirations and refresh on demand.

Method Summary

Modifier and Type	Method	Description
`abstract StreamToken`	`loadToken(StreamUserId userId)`	Returns a JWT that authenticates the given userId.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - loadToken
```
 abstract StreamToken loadToken(StreamUserId userId)
```
    Returns a JWT that authenticates the given userId.
    Called by the SDK when establishing a connection and whenever a token refresh is needed. Implementations may perform network requests and should be cancellable.
    Note: do not return a placeholder token or an empty string, throw an exception instead.
    
    Parameters:
    
    userId - The user identifier the token should be issued for.