Implemented the generic Auth feature.

Author: th37rose

server/api-service/lowcoder-sdk/src/main/java/org/lowcoder/sdk/auth/Oauth2SimpleAuthConfig.java

@@ -38,7 +38,7 @@ public String getAuthorizeUrl() {
             case AuthTypeConstants.GITHUB -> replaceAuthUrlClientIdPlaceholder(Oauth2Constants.GITHUB_AUTHORIZE_URL);
             case AuthTypeConstants.ORY -> replaceAuthUrlClientIdPlaceholder(Oauth2Constants.ORY_AUTHORIZE_URL);
             case AuthTypeConstants.KEYCLOAK -> replaceAuthUrlClientIdPlaceholder(Oauth2Constants.KEYCLOAK_AUTHORIZE_URL);
-            case AuthTypeConstants.GENERIC -> ((Oauth2GenericAuthConfig)this).getAuthorizationEndpoint();
+            case AuthTypeConstants.GENERIC -> replaceAuthUrlClientIdPlaceholder(((Oauth2GenericAuthConfig)this).getAuthorizationEndpoint());
             default -> null;
         };
     }

server/api-service/lowcoder-server/src/main/java/org/lowcoder/api/authentication/AuthenticationController.java

@@ -130,4 +130,24 @@ public Mono<ResponseView<List<APIKey>>> getAllAPIKeys() {
                 .collectList()
                 .map(ResponseView::success);
     }
+
+    /**
+     * This endpoint is to get IDP configuration
+     * @param issuerUri String
+     * @param source String
+     * @param sourceName String
+     * @param clientId String
+     * @param clientSecret String
+     * @return Oauth2GenericAuthConfig
+     */
+    @Override
+    public Mono<ResponseView<Oauth2GenericAuthConfig>> addOAuthProvider(String issuerUri,
+                                                                        String source,
+                                                                        String sourceName,
+                                                                        String clientId,
+                                                                        String clientSecret) {
+        return authenticationApiService.fetchAndParseConfiguration(issuerUri, source, sourceName, clientId, clientSecret)
+                .map(ResponseView::success);
+    }
+
 }

server/api-service/lowcoder-server/src/main/java/org/lowcoder/api/authentication/service/AuthenticationApiService.java

@@ -6,6 +6,7 @@
 import org.lowcoder.domain.authentication.FindAuthConfig;
 import org.lowcoder.domain.user.model.APIKey;
 import org.lowcoder.domain.user.model.AuthUser;
+import org.lowcoder.sdk.auth.Oauth2GenericAuthConfig;
 import org.springframework.web.server.ServerWebExchange;
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
@@ -29,4 +30,19 @@ public interface AuthenticationApiService {
     Mono<Void> deleteAPIKey(String authId);
 
     Flux<APIKey> findAPIKeys();
+
+    /**
+     * This method is to fetch and parse the OpenID configuration from the issuer URI.
+     * @param issuerUri String
+     * @param source String
+     * @param sourceName String
+     * @param clientId String
+     * @param clientSecret String
+     * @return Oauth2GenericAuthConfig
+     */
+    Mono<Oauth2GenericAuthConfig> fetchAndParseConfiguration(String issuerUri,
+                                                             String source,
+                                                             String sourceName,
+                                                             String clientId,
+                                                             String clientSecret);
 }

server/api-service/lowcoder-server/src/main/java/org/lowcoder/api/authentication/service/AuthenticationApiServiceImpl.java

@@ -333,6 +333,56 @@ public Flux<APIKey> findAPIKeys() {
                 );
     }
 
+    /**
+     * This method is to fetch and parse the OpenID configuration from the issuer URI.
+     * @param issuerUri String
+     * @param source String
+     * @param sourceName String
+     * @param clientId String
+     * @param clientSecret String
+     * @return Oauth2GenericAuthConfig
+     */
+    @Override
+    public Mono<Oauth2GenericAuthConfig> fetchAndParseConfiguration(String issuerUri,
+                                                                    String source,
+                                                                    String sourceName,
+                                                                    String clientId,
+                                                                    String clientSecret) {
+        String wellKnownUri = issuerUri + "/.well-known/openid-configuration";
+        return WebClientBuildHelper.builder()
+                .systemProxy()
+                .build()
+                .get()
+                .uri(wellKnownUri)
+                .retrieve()
+                .bodyToMono(Map.class)
+                .map(map -> mapToConfig(map, source, sourceName, clientId, clientSecret));
+    }
+
+    /**
+     * This method is to map to config for Generic Auth Provider
+     * @param map Object that comes from /.well-known endpoint for IDP Configuration
+     * @return Oauth2GenericAuthConfig
+     */
+    private Oauth2GenericAuthConfig mapToConfig(Map<String, Object> map,
+                                                String source,
+                                                String sourceName,
+                                                String clientId,
+                                                String clientSecret) {
+        return Oauth2GenericAuthConfig.builder()
+                .authType(AuthTypeConstants.GENERIC)
+                .source(source)
+                .sourceName(sourceName)
+                .clientId(clientId)
+                .clientSecret(clientSecret)
+                .issuerUri((String) map.get("issuer"))
+                .authorizationEndpoint((String) map.get("authorization_endpoint"))
+                .tokenEndpoint((String) map.get("token_endpoint"))
+                .userInfoEndpoint((String) map.get("userinfo_endpoint"))
+                .build();
+    }
+
+
     private Mono<Void> removeTokensByAuthId(String authId) {
         return sessionUserService.getVisitorOrgMemberCache()
                 .flatMapMany(orgMember -> orgMemberService.getOrganizationMembers(orgMember.getOrgId()))

server/api-service/lowcoder-server/src/main/java/org/lowcoder/api/authentication/service/factory/AuthConfigFactoryImpl.java

@@ -19,7 +19,6 @@ public class AuthConfigFactoryImpl implements AuthConfigFactory {
 
     @Override
     public AbstractAuthConfig build(AuthConfigRequest authConfigRequest, boolean enable) {
-        buildOauth2GenericAuthConfig(authConfigRequest, enable);
         return switch (authConfigRequest.getAuthType()) {
             case AuthTypeConstants.FORM -> buildEmailAuthConfig(authConfigRequest, enable);
             case AuthTypeConstants.GITHUB -> buildOauth2SimpleAuthConfig(GITHUB, GITHUB_NAME, authConfigRequest, enable);