be.looorent.micronaut.security.SecurityService Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of keycloak-micronaut-adapter Show documentation

Create API middleware to check Authorization headers against Keycloak

There is a newer version: 2.0.0

Show newest version

package be.looorent.micronaut.security;

import io.micronaut.http.HttpRequest;
import io.reactivex.Flowable;

import javax.inject.Singleton;

import static be.looorent.micronaut.security.SecurityErrorType.*;
import static io.reactivex.Flowable.fromCallable;
import static io.reactivex.schedulers.Schedulers.io;

/**
 * This service reads the Authorization header in an HTTP requests to validates its content.
 * @author Lorent Lempereur - [email protected]
 */
@Singleton
class SecurityService {

    private static final String HEADER_NAME = "Authorization";
    private static final String BEARER_SCHEME = "Bearer";

    private TokenParser tokenParser;

    SecurityService(TokenParser tokenParser) {
        if (tokenParser == null) {
            throw new IllegalArgumentException("No implementation of TokenParser has been found");
        }
        this.tokenParser = tokenParser;
    }

    Flowable readAndVerifyTokenIn(HttpRequest request)  {
        return fromCallable(() -> {
            String token = readTokenInHeadersOf(request);
            return tokenParser.parse(token);
        }).subscribeOn(io());
    }

    private String readTokenInHeadersOf(HttpRequest request) throws SecurityException {
        String authorizationHeader = request.getHeaders().get(HEADER_NAME);
        if (authorizationHeader == null) {
            throw AUTHORIZATION_HEADER_MISSING.toException();
        }

        String[] schemeAndToken = authorizationHeader.split(" ");
        if (schemeAndToken.length != 2) {
            throw AUTHORIZATION_HEADER_WRONG_FORMAT.toException();
        }

        if (!BEARER_SCHEME.equalsIgnoreCase(schemeAndToken[0])) {
            throw AUTHORIZATION_HEADER_WRONG_SCHEME.toException();
        }
        return schemeAndToken[1];
    }
}