content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You 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.apache.atlas.web.security;
  
  import org.apache.atlas.ApplicationProperties;
  import org.apache.commons.configuration.Configuration;
  import org.keycloak.adapters.springsecurity.authentication.KeycloakAuthenticationProvider;
  import org.keycloak.adapters.springsecurity.token.KeycloakAuthenticationToken;
  import org.springframework.security.core.Authentication;
  import org.springframework.security.core.GrantedAuthority;
  import org.springframework.security.core.authority.SimpleGrantedAuthority;
  import org.springframework.stereotype.Component;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Map;
  
  @Component
  public class AtlasKeycloakAuthenticationProvider extends AtlasAbstractAuthenticationProvider {
      private final boolean groupsFromUGI;
      private final String  groupsClaim;
  
      private final KeycloakAuthenticationProvider keycloakAuthenticationProvider;
  
      public AtlasKeycloakAuthenticationProvider() throws Exception {
          this.keycloakAuthenticationProvider = new KeycloakAuthenticationProvider();
  
          Configuration configuration = ApplicationProperties.get();
  
          this.groupsFromUGI = configuration.getBoolean("atlas.authentication.method.keycloak.ugi-groups", true);
          this.groupsClaim   = configuration.getString("atlas.authentication.method.keycloak.groups_claim");
      }
  
      @Override
      public Authentication authenticate(Authentication authentication) {
          authentication = keycloakAuthenticationProvider.authenticate(authentication);
  
          if (groupsFromUGI) {
              List<GrantedAuthority>      groups = getAuthoritiesFromUGI(authentication.getName());
              KeycloakAuthenticationToken token  = (KeycloakAuthenticationToken) authentication;
  
              authentication = new KeycloakAuthenticationToken(token.getAccount(), token.isInteractive(), groups);
          } else if (groupsClaim != null) {
              KeycloakAuthenticationToken token  = (KeycloakAuthenticationToken) authentication;
              Map<String, Object>         claims = token.getAccount().getKeycloakSecurityContext().getToken().getOtherClaims();
  
              if (claims.containsKey(groupsClaim)) {
                  List<String>           membership         = (List<String>) claims.get(groupsClaim);
                  List<GrantedAuthority> grantedAuthorities = new ArrayList<>();
  
                  for (String group : membership) {
                      grantedAuthorities.add(new SimpleGrantedAuthority(group));
                  }
  
                  authentication = new KeycloakAuthenticationToken(token.getAccount(), token.isInteractive(), grantedAuthorities);
              }
          }
  
          return authentication;
      }
  
      @Override
      public boolean supports(Class<?> aClass) {
          return keycloakAuthenticationProvider.supports(aClass);
      }
  }
  