BE: Impl custom authentication page

api/src/main/java/io/kafbat/ui/config/auth/AbstractAuthSecurityConfig.java

@@ -18,7 +18,8 @@ protected AbstractAuthSecurityConfig() {
       "/login",
       "/logout",
       "/oauth2/**",
-      "/static/**"
+      "/static/**",
+      "/api/config/authentication"
   };
 
 }

api/src/main/java/io/kafbat/ui/controller/ApplicationConfigController.java

@@ -6,6 +6,7 @@
 import io.kafbat.ui.api.ApplicationConfigApi;
 import io.kafbat.ui.config.ClustersProperties;
 import io.kafbat.ui.model.ActionDTO;
+import io.kafbat.ui.model.AppAuthenticationSettingsDTO;
 import io.kafbat.ui.model.ApplicationConfigDTO;
 import io.kafbat.ui.model.ApplicationConfigPropertiesDTO;
 import io.kafbat.ui.model.ApplicationConfigValidationDTO;
@@ -66,6 +67,13 @@ public Mono<ResponseEntity<ApplicationInfoDTO>> getApplicationInfo(ServerWebExch
     return Mono.just(applicationInfoService.getApplicationInfo()).map(ResponseEntity::ok);
   }
 
+  @Override
+  public Mono<ResponseEntity<AppAuthenticationSettingsDTO>> getAuthenticationSettings(
+      ServerWebExchange exchange) {
+    return Mono.just(applicationInfoService.getAuthenticationProperties())
+        .map(ResponseEntity::ok);
+  }
+
   @Override
   public Mono<ResponseEntity<ApplicationConfigDTO>> getCurrentConfig(ServerWebExchange exchange) {
     var context = AccessContext.builder()
@@ -109,7 +117,7 @@ public Mono<ResponseEntity<UploadedFileInfoDTO>> uploadConfigRelatedFile(Flux<Pa
         .then(fileFlux.single())
         .flatMap(file ->
             dynamicConfigOperations.uploadConfigRelatedFile((FilePart) file)
-                .map(path -> new UploadedFileInfoDTO().location(path.toString()))
+                .map(path -> new UploadedFileInfoDTO(path.toString()))
                 .map(ResponseEntity::ok))
         .doOnEach(sig -> audit(context, sig));
   }

api/src/main/java/io/kafbat/ui/controller/AuthController.java → api/src/main/java/io/kafbat/ui/controller/AuthenticationController.java

@@ -13,13 +13,13 @@
 @RestController
 @RequiredArgsConstructor
 @Slf4j
-public class AuthController {
+public class AuthenticationController {
 
   @GetMapping(value = "/auth", produces = {"text/html"})
   public Mono<byte[]> getAuth(ServerWebExchange exchange) {
     Mono<CsrfToken> token = exchange.getAttributeOrDefault(CsrfToken.class.getName(), Mono.empty());
     return token
-        .map(AuthController::csrfToken)
+        .map(AuthenticationController::csrfToken)
         .defaultIfEmpty("")
         .map(csrfTokenHtmlInput -> createPage(exchange, csrfTokenHtmlInput));
   }

api/src/main/java/io/kafbat/ui/controller/AccessController.java → api/src/main/java/io/kafbat/ui/controller/AuthorizationController.java

@@ -26,7 +26,7 @@
 @RestController
 @RequiredArgsConstructor
 @Slf4j
-public class AccessController implements AuthorizationApi {
+public class AuthorizationController implements AuthorizationApi {
 
   private final AccessControlService accessControlService;
 

api/src/main/java/io/kafbat/ui/service/ApplicationInfoService.java

@@ -1,37 +1,51 @@
 package io.kafbat.ui.service;
 
+import static io.kafbat.ui.api.model.AuthType.DISABLED;
+import static io.kafbat.ui.api.model.AuthType.OAUTH2;
 import static io.kafbat.ui.model.ApplicationInfoDTO.EnabledFeaturesEnum;
 import static io.kafbat.ui.util.GithubReleaseInfo.GITHUB_RELEASE_INFO_TIMEOUT;
 
 import com.google.common.annotations.VisibleForTesting;
+import com.google.common.collect.Streams;
+import io.kafbat.ui.model.AppAuthenticationSettingsDTO;
 import io.kafbat.ui.model.ApplicationInfoBuildDTO;
 import io.kafbat.ui.model.ApplicationInfoDTO;
 import io.kafbat.ui.model.ApplicationInfoLatestReleaseDTO;
+import io.kafbat.ui.model.AuthTypeDTO;
+import io.kafbat.ui.model.OAuthProviderDTO;
 import io.kafbat.ui.util.DynamicConfigOperations;
 import io.kafbat.ui.util.GithubReleaseInfo;
 import java.time.format.DateTimeFormatter;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 import java.util.Optional;
 import java.util.Properties;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.boot.info.BuildProperties;
 import org.springframework.boot.info.GitProperties;
+import org.springframework.context.ApplicationContext;
+import org.springframework.core.ResolvableType;
 import org.springframework.scheduling.annotation.Scheduled;
+import org.springframework.security.oauth2.client.registration.ClientRegistration;
+import org.springframework.security.oauth2.core.AuthorizationGrantType;
 import org.springframework.stereotype.Service;
 
 @Service
 public class ApplicationInfoService {
   private final GithubReleaseInfo githubReleaseInfo;
+  private final ApplicationContext applicationContext;
   private final DynamicConfigOperations dynamicConfigOperations;
   private final BuildProperties buildProperties;
   private final GitProperties gitProperties;
 
   public ApplicationInfoService(DynamicConfigOperations dynamicConfigOperations,
+                                ApplicationContext applicationContext,
                                 @Autowired(required = false) BuildProperties buildProperties,
                                 @Autowired(required = false) GitProperties gitProperties,
                                 @Value("${" + GITHUB_RELEASE_INFO_TIMEOUT + ":10}") int githubApiMaxWaitTime) {
+    this.applicationContext = applicationContext;
     this.dynamicConfigOperations = dynamicConfigOperations;
     this.buildProperties = Optional.ofNullable(buildProperties).orElse(new BuildProperties(new Properties()));
     this.gitProperties = Optional.ofNullable(gitProperties).orElse(new GitProperties(new Properties()));
@@ -70,6 +84,38 @@ private List<EnabledFeaturesEnum> getEnabledFeatures() {
     return enabledFeatures;
   }
 
+  public AppAuthenticationSettingsDTO getAuthenticationProperties() {
+    return new AppAuthenticationSettingsDTO()
+        .authType(AuthTypeDTO.fromValue(getAuthType()))
+        .oAuthProviders(getOAuthProviders());
+  }
+
+  private String getAuthType() {
+    return Optional.ofNullable(applicationContext.getEnvironment().getProperty("auth.type"))
+        .orElse(DISABLED.getValue());
+  }
+
+  @SuppressWarnings("unchecked")
+  private List<OAuthProviderDTO> getOAuthProviders() {
+    if (!getAuthType().equalsIgnoreCase(OAUTH2.getValue())) {
+      return Collections.emptyList();
+    }
+    var type = ResolvableType.forClassWithGenerics(Iterable.class, ClientRegistration.class);
+    String[] names = this.applicationContext.getBeanNamesForType(type);
+    var bean = (Iterable<ClientRegistration>) (names.length == 1 ? this.applicationContext.getBean(names[0]) : null);
+
+    if (bean == null) {
+      return Collections.emptyList();
+    }
+
+    return Streams.stream(bean.iterator())
+        .filter(r -> AuthorizationGrantType.AUTHORIZATION_CODE.equals(r.getAuthorizationGrantType()))
+        .map(r -> new OAuthProviderDTO()
+            .clientName(r.getClientName())
+            .authorizationUri("/oauth2/authorization/" + r.getRegistrationId()))
+        .toList();
+  }
+
   // updating on startup and every hour
   @Scheduled(fixedRateString = "${github-release-info-update-rate:3600000}")
   public void updateGithubReleaseInfo() {

contract/src/main/resources/swagger/kafbat-ui-api.yaml

@@ -2150,7 +2150,7 @@ paths:
     get:
       tags:
         - Authorization
-      summary: Get user authentication related info
+      summary: Get user authorization related info
       operationId: getUserAuthInfo
       responses:
         200:
@@ -2244,6 +2244,20 @@ paths:
               schema:
                 $ref: '#/components/schemas/UploadedFileInfo'
 
+  /api/config/authentication:
+    get:
+      tags:
+        - ApplicationConfig
+      summary: Get authentication methods enabled for the app and other related settings
+      operationId: getAuthenticationSettings
+      responses:
+        200:
+          description: OK
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/AppAuthenticationSettings'
+
 components:
   schemas:
     TopicSerdeSuggestion:
@@ -2354,6 +2368,32 @@ components:
             htmlUrl:
               type: string
 
+    AppAuthenticationSettings:
+      type: object
+      properties:
+        authType:
+          $ref: '#/components/schemas/AuthType'
+        oAuthProviders:
+          type: array
+          items:
+            $ref: '#/components/schemas/OAuthProvider'
+
+    OAuthProvider:
+      type: object
+      properties:
+        clientName:
+          type: string
+        authorizationUri:
+          type: string
+
+    AuthType:
+      type: string
+      enum:
+        - DISABLED
+        - OAUTH2
+        - LOGIN_FORM
+        - LDAP
+
     Cluster:
       type: object
       properties: