ISSUE-824 Enabled basic authecation (#833)

kafka-ui-api/src/main/java/com/provectus/kafka/ui/config/OAuthSecurityConfig.java

@@ -1,17 +1,29 @@
 package com.provectus.kafka.ui.config;
 
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
+import org.springframework.context.ApplicationContext;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.security.config.annotation.web.reactive.EnableWebFluxSecurity;
 import org.springframework.security.config.web.server.ServerHttpSecurity;
 import org.springframework.security.web.server.SecurityWebFilterChain;
+import org.springframework.util.ClassUtils;
 
 @Configuration
 @EnableWebFluxSecurity
 @ConditionalOnProperty(value = "auth.enabled", havingValue = "true")
 public class OAuthSecurityConfig {
 
+  public static final String REACTIVE_CLIENT_REGISTRATION_REPOSITORY_CLASSNAME =
+      "org.springframework.security.oauth2.client.registration."
+          + "ReactiveClientRegistrationRepository";
+
+  private static final boolean isOAuth2Present = ClassUtils.isPresent(
+      REACTIVE_CLIENT_REGISTRATION_REPOSITORY_CLASSNAME,
+      OAuthSecurityConfig.class.getClassLoader()
+  );
+
   private static final String[] AUTH_WHITELIST = {
       "/css/**",
       "/js/**",
@@ -24,17 +36,43 @@ public class OAuthSecurityConfig {
       "/oauth2/**"
   };
 
+  @Autowired
+  ApplicationContext context;
+
   @Bean
   public SecurityWebFilterChain configure(ServerHttpSecurity http) {
-    return http.authorizeExchange()
+    http.authorizeExchange()
         .pathMatchers(AUTH_WHITELIST).permitAll()
-        .anyExchange().authenticated()
-        .and()
-        .oauth2Login()
-        .and()
-        .csrf().disable()
-        .build();
+        .anyExchange()
+        .authenticated();
+
+    if (isOAuth2Present && OAuth2ClasspathGuard.shouldConfigure(this.context)) {
+      OAuth2ClasspathGuard.configure(this.context, http);
+    } else {
+      http
+          .httpBasic().and()
+          .formLogin();
+    }
+
+    SecurityWebFilterChain result = http.csrf().disable().build();
+    return result;
   }
 
+  private static class OAuth2ClasspathGuard {
+    static void configure(ApplicationContext context, ServerHttpSecurity http) {
+      http
+          .oauth2Login().and()
+          .oauth2Client();
+    }
+
+    static boolean shouldConfigure(ApplicationContext context) {
+      ClassLoader loader = context.getClassLoader();
+      Class<?> reactiveClientRegistrationRepositoryClass =
+          ClassUtils.resolveClassName(REACTIVE_CLIENT_REGISTRATION_REPOSITORY_CLASSNAME, loader);
+      return context.getBeanNamesForType(reactiveClientRegistrationRepositoryClass).length == 1;
+    }
+  }
+
+
 }