Handle Userstore failures gracefully without affecting other Userstores

core/org.wso2.carbon.user.core/src/main/java/org/wso2/carbon/user/core/CircuitBreakerOpenException.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2024, WSO2 LLC. (http://www.wso2.com).
+ *
+ * WSO2 Inc. 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.wso2.carbon.user.core;
+
+/**
+ * The exception to throw when the Circuit Breaker triggers for user stores.
+ */
+public class CircuitBreakerOpenException extends UserStoreException {
+
+    public CircuitBreakerOpenException(String message, Throwable cause) {
+
+        super(message, cause);
+    }
+
+    public CircuitBreakerOpenException(String message, String errorCode, Throwable cause) {
+
+        super(message, errorCode, cause);
+    }
+
+    public CircuitBreakerOpenException(String message, String errorCode) {
+
+        super(message, errorCode);
+    }
+
+    public CircuitBreakerOpenException(String message) {
+
+        super(message);
+    }
+
+    public CircuitBreakerOpenException(Throwable cause) {
+
+        super(cause);
+    }
+}

core/org.wso2.carbon.user.core/src/main/java/org/wso2/carbon/user/core/UserCoreConstants.java

@@ -121,6 +121,10 @@ public class UserCoreConstants {
     public static final String USER_LOCKED = "true";
     public static final String USER_UNLOCKED = "false";
 
+    // Server level config introduced for backward compatibility with the CircuitBreaker.
+    public static final String PROP_ENABLE_CIRCUIT_BREAKER_FOR_USERSTORE =
+            "UserStore.enableCircuitBreakerForUserStores";
+
     public static final class RealmConfig {
         public static final String LOCAL_NAME_USER_MANAGER = "UserManager";
         public static final String LOCAL_NAME_REALM = "Realm";
@@ -239,6 +243,9 @@ public static final class RealmConfig {
         public static final String LEADING_OR_TRAILING_SPACE_ALLOWED_IN_USERNAME =
                 "LeadingOrTrailingSpaceAllowedInUserName";
         public static final String PROPERTY_USER_ID_ENABLED = "UserIDEnabled";
+
+        public static final String CIRCUIT_STATE_OPEN = "open";
+        public static final String CIRCUIT_STATE_CLOSE = "close";
     }
 
     public static final class ClaimTypeURIs {

core/org.wso2.carbon.user.core/src/main/java/org/wso2/carbon/user/core/UserStoreConfigConstants.java

@@ -178,8 +178,18 @@ public class UserStoreConfigConstants {
     public static final String CONNECTION_RETRY_DELAY_DESCRIPTION = "Specifies waiting time in milliseconds"
             + " inorder to establish the connection after couple of failure attempts.";
     public static final int DEFAULT_CONNECTION_RETRY_DELAY_IN_MILLISECONDS = 120000;
+    public static final String MAX_CONNECTION_RETRY_DELAY_IN_MILLISECONDS =
+            "UserStore.maxConnectionRetryDelayInMilliSeconds";
+
     public static final String OBJECT_GUID = "objectGuid";
 
+    public static final String CONNECTION_RETRY_COUNT = "ConnectionRetryCount";
+    public static final int DEFAULT_CONNECTION_RETRY_COUNT = 2;
+    public static final String MAX_CONNECTION_RETRY_COUNT = "UserStore.maxConnectionRetryCount";
+    public static final String CONNECTION_RETRY_COUNT_DISPLAY_NAME = "Connection Retry Count";
+    public static final String CONNECTION_RETRY_COUNT_DESCRIPTION = "Specifies connection retry times"
+            + " inorder to re-establish the connection on failure";
+
     // Property for specify case insensitivity for User stores.
     public static final String CASE_INSENSITIVE_USERNAME = "CaseInsensitiveUsername";
     public static final String CASE_INSENSITIVE_USERNAME_DESCRIPTION = "Whether the username is case sensitive or not";
@@ -198,4 +208,5 @@ public class UserStoreConfigConstants {
     public static final String singleValuedAttributesDescription = "Comma-separated list of attributes that need to " +
             "skip multi-valued attribute separation";
     public static final String singleValuedAttributesDisplayName = "Single Valued Attributes";
+
 }

core/org.wso2.carbon.user.core/src/main/java/org/wso2/carbon/user/core/jdbc/JDBCUserStoreConstants.java

@@ -184,6 +184,17 @@ public class JDBCUserStoreConstants {
                 "The default auto-commit state of connections created by this pool",
                 new Property[] { CONNECTION.getProperty(), BOOLEAN.getProperty(), FALSE.getProperty() });
 
+        /* Added for circuit breaker implementation. */
+        setAdvancedProperty(UserStoreConfigConstants.CONNECTION_RETRY_COUNT, UserStoreConfigConstants
+                        .CONNECTION_RETRY_COUNT_DISPLAY_NAME, String.valueOf(UserStoreConfigConstants
+                        .DEFAULT_CONNECTION_RETRY_COUNT), UserStoreConfigConstants.CONNECTION_RETRY_COUNT_DESCRIPTION,
+                new Property[] { CONNECTION.getProperty(), NUMBER.getProperty(), FALSE.getProperty() });
+        setAdvancedProperty(UserStoreConfigConstants.CONNECTION_RETRY_DELAY, UserStoreConfigConstants.
+                CONNECTION_RETRY_DELAY_DISPLAY_NAME, String.valueOf(UserStoreConfigConstants
+                .DEFAULT_CONNECTION_RETRY_DELAY_IN_MILLISECONDS), UserStoreConfigConstants
+                .CONNECTION_RETRY_DELAY_DESCRIPTION, new Property[] { CONNECTION.getProperty(), NUMBER.getProperty(),
+                FALSE.getProperty() });
+
         setAdvancedProperty(JDBCRealmConstants.DEFAULT_READ_ONLY, "Default Read Only", "",
                 "The default read-only state of connections created by this pool",
                 new Property[] { CONNECTION.getProperty(), BOOLEAN.getProperty(), FALSE.getProperty() });