framework_v2/internal/middleware/grpc/auth.go

package grpc

import (
	"context"
	auth2 "framework_v2/internal/providers/auth"
	"framework_v2/internal/providers/config"
	"framework_v2/internal/providers/jwks"
	"framework_v2/internal/providers/logger"
	"github.com/grpc-ecosystem/go-grpc-middleware/v2/interceptors/auth"
	"github.com/grpc-ecosystem/go-grpc-middleware/v2/interceptors/logging"
	"github.com/mitchellh/mapstructure"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"
)

func JwtAuth(ctx context.Context) (context.Context, error) {
	tokenString, err := auth.AuthFromMD(ctx, "bearer")
	if err != nil {
		return nil, err
	}

	sub := "anonymous"
	var jwtIdToken *auth2.User

	if config.Config.DebugMode.Enable {
		jwtIdToken.Token.Sub = sub
	} else {
		token, err := jwks.ParseJWT(tokenString)
		if err != nil {
			return nil, status.Errorf(codes.Unauthenticated, "invalid auth token: %v", err)
		}
		sub, err = token.Claims.GetSubject()
		if err != nil {
			return nil, status.Errorf(codes.Unauthenticated, "unable get token sub: %v", err)
		}

		err = mapstructure.Decode(token.Claims, &jwtIdToken)
		if err != nil {
			logger.Logger.Error("Failed to map token claims to JwtIDToken struct.\nError: " + err.Error())
			return nil, err
		}
	}

	ctx = logging.InjectFields(ctx, logging.Fields{"auth.sub", sub})

	return context.WithValue(ctx, "auth", jwtIdToken), nil
}