get totalResults by user count

components/org.wso2.carbon.identity.scim2.common/src/main/java/org/wso2/carbon/identity/scim2/common/impl/SCIMUserManager.java

@@ -1440,7 +1440,13 @@ private UsersGetResponse filterUsersBySingleAttribute(ExpressionNode node, Map<S
                     maxLimit = Math.max(maxLimit, limit);
                 }
                 // Get total users based on the filter query without depending on pagination params.
-                totalResults += filterUsers(node, 1, maxLimit, sortBy, sortOrder, domainName).size();
+                if(SCIMCommonUtils.isRetrieveTotalResultsByUserCountEnabled()) {
+                    //Get the total user count by the filter query.
+                    totalResults += getUserCountByAttribute(node, 1, maxLimit, sortBy, sortOrder, domainName);
+                } else {
+                    totalResults += filterUsers(node, 1, maxLimit, sortBy, sortOrder, domainName).size();
+                }
+
             } else {
                 totalResults += users.size();
             }
@@ -1451,6 +1457,29 @@ private UsersGetResponse filterUsersBySingleAttribute(ExpressionNode node, Map<S
         return getDetailedUsers(filteredUsers, totalResults);
     }
 
+    /**
+     * method to get user count by filtering parameter.
+     *
+     * @param node       Expression node for single attribute filtering
+     * @param offset     Starting index of the count
+     * @param limit      Counting value
+     * @param sortBy     SortBy
+     * @param sortOrder  Sorting order
+     * @param domainName Domain to run the filter
+     * @return User count
+     * @throws BadRequestException
+     * @throws CharonException
+     */
+    private int getUserCountByAttribute(Node node, int offset, int limit, String sortBy,
+                             String sortOrder, String domainName) throws BadRequestException, CharonException {
+
+        if (SCIMConstants.UserSchemaConstants.GROUP_URI.equals(((ExpressionNode) node).getAttributeValue())) {
+            getUserCountByGroup(node, domainName);
+        }
+
+        return filterUsers(node, 1, limit, sortBy, sortOrder, domainName).size();
+    }
+
     /**
      * Method to check whether the all configured user stores are JDBC.
      *
@@ -1688,6 +1717,54 @@ private Set<org.wso2.carbon.user.core.common.User> filterUsers(Node node, int of
         }
     }
 
+    /**
+     * Method to get User Count by Group filter
+     *
+     * @param node       Expression or Operation node.
+     * @param domainName Domain name.
+     * @return User count for the filtered group.
+     * @throws CharonException
+     * @throws BadRequestException
+     */
+    private int getUserCountByGroup(Node node, String domainName)
+            throws CharonException, BadRequestException {
+
+        int count = 0;
+        // Set filter values.
+        String attributeName = ((ExpressionNode) node).getAttributeValue();
+        String filterOperation = ((ExpressionNode) node).getOperation();
+        String attributeValue = ((ExpressionNode) node).getValue();
+
+        /*
+        If there is a domain and if the domain separator is not found in the attribute value, append the domain
+        with the domain separator in front of the new attribute value.
+        */
+        attributeValue = UserCoreUtil.addDomainToName(((ExpressionNode) node).getValue(), domainName);
+
+        try {
+            List<String> roleNames = getRoleNames(attributeName, filterOperation, attributeValue);
+            count = getUserCountForRole(roleNames);
+            return count;
+        } catch (UserStoreException e) {
+            String errorMessage = String.format("Error while filtering the users for filter with attribute name: "
+                            + "%s, filter operation: %s and attribute value: %s.", attributeName, filterOperation,
+                    attributeValue);
+            throw resolveError(e, errorMessage);
+        }
+    }
+
+    private int getUserCountForRole(List<String> roleNames) throws
+                        org.wso2.carbon.user.core.UserStoreException {
+
+        int count = 0;
+        if (roleNames != null) {
+            for (String roleName : roleNames) {
+                count += carbonUM.getUserCountForRole(roleName);
+            }
+        }
+        return count;
+    }
+
     /**
      * Method to perform a multiple domain search when the domain is not specified in the request. The same function
      * can be used to listing users by passing a condition for conditionForListingUsers parameter.

components/org.wso2.carbon.identity.scim2.common/src/main/java/org/wso2/carbon/identity/scim2/common/utils/SCIMCommonConstants.java

@@ -102,6 +102,8 @@ public class SCIMCommonConstants {
             "SCIM2.ConsiderMaxLimitForTotalResult";
     public static final String SCIM_ENABLE_CONSIDER_TOTAL_RECORDS_FOR_TOTAL_RESULT_OF_LDAP =
             "SCIM2.ConsiderTotalRecordsForTotalResultOfLDAP";
+    public static final String SCIM_ENABLE_RETRIEVE_TOTAL_RESULTS_BY_User_Count =
+            "SCIM2.EnableRetrieveTotalResultsByUserCount";
     public static final String SCIM_ENABLE_MANDATE_DOMAIN_FOR_GROUPNAMES_IN_GROUPS_RESPONSE =
             "SCIM2.MandateDomainForGroupNamesInGroupsResponse";
     public static final String SCIM_ENABLE_MANDATE_DOMAIN_FOR_USERNAMES_AND_GROUPNAMES_IN_RESPONSE =

components/org.wso2.carbon.identity.scim2.common/src/main/java/org/wso2/carbon/identity/scim2/common/utils/SCIMCommonUtils.java

@@ -619,6 +619,17 @@ public static boolean isEnterpriseUserExtensionEnabled() {
                 .getProperty(SCIMCommonConstants.ENTERPRISE_USER_EXTENSION_ENABLED));
     }
 
+    /**
+     * Checks whether the identity.xml config is available to retrieve totalResults by user count.
+     *
+     * @return whether 'RetrieveTotalResultsByUserCount' property is enabled in identity.xml.
+     */
+    public static boolean isRetrieveTotalResultsByUserCountEnabled() {
+
+        return Boolean.parseBoolean(IdentityUtil.getProperty(
+                SCIMCommonConstants.SCIM_ENABLE_RETRIEVE_TOTAL_RESULTS_BY_User_Count));
+    }
+
     /**
      * Checks whether the identity.xml config is available to notify userstore availability.
      *