org.bremersee.security.authentication.KeycloakJwtConverter Maven / Gradle / Ivy
/*
* Copyright 2018 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.bremersee.security.authentication;
import com.jayway.jsonpath.DocumentContext;
import com.jayway.jsonpath.JsonPath;
import com.jayway.jsonpath.Option;
import java.util.Collections;
import java.util.List;
import java.util.Set;
import java.util.stream.Collectors;
import net.minidev.json.JSONValue;
import org.springframework.core.convert.converter.Converter;
import org.springframework.security.core.GrantedAuthority;
import org.springframework.security.core.authority.SimpleGrantedAuthority;
import org.springframework.security.oauth2.jwt.Jwt;
import org.springframework.security.oauth2.server.resource.authentication.JwtAuthenticationToken;
import org.springframework.util.StringUtils;
/**
* A JWT converter for the keycloak identity provider. It use the json path {@code
* $.realm_access.roles} to extract the roles from the token.
*
* @author Christian Bremer
*/
public class KeycloakJwtConverter implements Converter {
private static final String JSON_ROLES_PATH = "$.realm_access.roles";
private static final com.jayway.jsonpath.Configuration jsonPathConf
= com.jayway.jsonpath.Configuration.builder().options(Option.SUPPRESS_EXCEPTIONS).build();
/**
* Instantiates a new keycloak jwt converter.
*/
@SuppressWarnings("WeakerAccess")
public KeycloakJwtConverter() {
}
@Override
public JwtAuthenticationToken convert(final Jwt jwt) {
final String jsonStr = JSONValue.toJSONString(jwt.getClaims());
final DocumentContext ctx = JsonPath.parse(jsonStr, jsonPathConf);
final List roles = ctx.read(JSON_ROLES_PATH, List.class);
final Set authorities;
if (roles == null || roles.isEmpty()) {
authorities = Collections.emptySet();
} else {
authorities = roles
.stream()
.map(this::buildGrantedAuthority)
.collect(Collectors.toSet());
}
return new KeycloakJwtAuthenticationToken(jwt, authorities);
}
private GrantedAuthority buildGrantedAuthority(final Object name) {
final SimpleGrantedAuthority authority;
if (name instanceof String && StringUtils.hasText((String) name)) {
authority = new SimpleGrantedAuthority(((String) name).startsWith("ROLE_")
? (String) name : "ROLE_" + name);
} else {
authority = new SimpleGrantedAuthority("ROLE_NULL");
}
return authority;
}
}