Better logs for not succeeded policy authentication schemes

[luccawilli]

Summary

In the current version of aspnetcore AuthorizationMiddleware it is pretty hard to determine which authentication schemes or which policy failed. Even if debug logs are enabled, no info gets displayed.

Motivation and goals

• Easier debugging / error finding for false defined policies or bad requests

In scope

• aspnet service with multiple authentication policies defined.

Out of scope

• aspnet service without authentication or authentication policies

Risks / unknowns

• Logger null --> small concern
• Too many logs --> Choose Debug-Level

Examples

Add a logger to AuthorizationMiddleware

private readonly ILogger<AuthorizationMiddleware> _logger;

Log if not succeded and a policy is defined

if (authenticateResult != null && !authenticateResult.Succeeded)
{
    _logger.LogDebug("Policy authentication schemes {policyName} did not succeed", String.Join(", ", policy.AuthenticationSchemes));
}