Cursor based pagination for SCIM resources phase 1

modules/charon-core/src/main/java/org/wso2/charon3/core/config/CharonConfiguration.java

@@ -36,6 +36,7 @@ public class CharonConfiguration implements Configuration {
     private int maxPayLoadSize;
     private int maxResults;
     private ArrayList<Object[]> authenticationSchemes = new ArrayList<Object[]>();
+    private boolean cursorSupport;
 
     //default count value for pagination
     private int count;
@@ -78,6 +79,15 @@ public void setFilterSupport(boolean supported, int maxResults) {
         this.maxResults = maxResults;
     }
 
+    /**
+     * Set cursor pagination support
+     * @param supported
+     */
+    public void setCursorPaginationSupport(boolean supported) {
+
+        this.cursorSupport = supported;
+    }
+
     /*
      * set Change Password Support
      * @param supported
@@ -145,6 +155,7 @@ public HashMap<String, Object> getConfig() {
         configMap.put(SCIMConfigConstants.PATCH, patchSupport);
         configMap.put(SCIMConfigConstants.AUTHENTICATION_SCHEMES, authenticationSchemes);
         configMap.put(SCIMConfigConstants.PAGINATION_DEFAULT_COUNT, count);
+        configMap.put(SCIMConfigConstants.CURSOR, cursorSupport);
         return  configMap;
     }
 

modules/charon-core/src/main/java/org/wso2/charon3/core/config/SCIMConfigConstants.java

@@ -47,6 +47,7 @@ public class SCIMConfigConstants {
     public static final String AUTHENTICATION_SCHEMES = "authenticationSchemes";
     public static final String SCIM_SCHEMA_EXTENSION_CONFIG = "scim2-schema-extension.config";
     public static final String PAGINATION_DEFAULT_COUNT = "pagination-default-count";
+    public static final String CURSOR = "cursor";
 
 
 }

modules/charon-core/src/main/java/org/wso2/charon3/core/encoder/JSONDecoder.java

@@ -830,7 +830,13 @@ public SearchRequest decodeSearchRequestBody(String scimResourceString,
             searchRequest.setExcludedAttributes(excludedAttributes);
             searchRequest.setSchema((String) schemas.get(0));
             searchRequest.setCountStr(decodedJsonObj.optString(SCIMConstants.OperationalConstants.COUNT));
-            searchRequest.setStartIndexStr(decodedJsonObj.optString(SCIMConstants.OperationalConstants.START_INDEX));
+            if (!decodedJsonObj.optString(SCIMConstants.OperationalConstants.START_INDEX).equals("")) {
+                searchRequest.setStartIndexStr(
+                        decodedJsonObj.optString(SCIMConstants.OperationalConstants.START_INDEX));
+            }
+            if (decodedJsonObj.has(SCIMConstants.OperationalConstants.CURSOR)) {
+                searchRequest.setCursor(decodedJsonObj.optString(SCIMConstants.OperationalConstants.CURSOR));
+            }
             searchRequest.setDomainName(decodedJsonObj.optString(SCIMConstants.OperationalConstants.DOMAIN));
             searchRequest.setFilter(rootNode);
             if (!decodedJsonObj.optString(SCIMConstants.OperationalConstants.SORT_BY).equals("")) {

modules/charon-core/src/main/java/org/wso2/charon3/core/encoder/JSONEncoder.java

@@ -418,6 +418,10 @@ public String buildServiceProviderConfigJsonBody(HashMap<String, Object> config)
         changePasswordObject.put(SCIMConstants.ServiceProviderConfigSchemaConstants.SUPPORTED,
                 config.get(SCIMConfigConstants.CHNAGE_PASSWORD));
 
+        JSONObject paginationObject = new JSONObject();
+        paginationObject.put(SCIMConstants.ServiceProviderConfigSchemaConstants.CURSOR,
+                config.get(SCIMConfigConstants.CURSOR));
+
         JSONArray authenticationSchemesArray = new JSONArray();
         ArrayList<Object[]> values = (ArrayList<Object[]>) config.get(SCIMConfigConstants.AUTHENTICATION_SCHEMES);
 
@@ -457,6 +461,8 @@ public String buildServiceProviderConfigJsonBody(HashMap<String, Object> config)
                 etagObject);
         rootObject.put(SCIMConstants.ServiceProviderConfigSchemaConstants.AUTHENTICATION_SCHEMAS,
                 authenticationSchemesArray);
+        rootObject.put(SCIMConstants.ServiceProviderConfigSchemaConstants.PAGINATION,
+                paginationObject);
 
         return rootObject.toString();
 

modules/charon-core/src/main/java/org/wso2/charon3/core/extensions/UserManager.java

@@ -24,6 +24,7 @@
 import org.wso2.charon3.core.exceptions.NotImplementedException;
 import org.wso2.charon3.core.objects.Group;
 import org.wso2.charon3.core.objects.User;
+import org.wso2.charon3.core.objects.plainobjects.Cursor;
 import org.wso2.charon3.core.objects.plainobjects.GroupsGetResponse;
 import org.wso2.charon3.core.objects.plainobjects.UsersGetResponse;
 import org.wso2.charon3.core.schema.AttributeSchema;
@@ -53,22 +54,44 @@ public void deleteUser(String userId)
             throws NotFoundException, CharonException, NotImplementedException, BadRequestException;
 
     /**
-     * List users with Get.
+     * List users with Get using offset pagination.
      *
-     * @param node               Node
-     * @param startIndex         Start Index
-     * @param count              Count
-     * @param sortBy             Sort by
-     * @param sortOrder          Sort order
-     * @param domainName         Domain name
-     * @param requiredAttributes Required user attributes
-     * @return Users with requested attributes
-     * @throws CharonException         Error while listing users
-     * @throws NotImplementedException Operation note implemented
-     * @throws BadRequestException     Bad request
+     * @param node               Tree node built based on the filtering conditions.
+     * @param startIndex         Start Index.
+     * @param count              Count.
+     * @param sortBy             Sort by.
+     * @param sortOrder          Sort order.
+     * @param domainName         Domain name.
+     * @param requiredAttributes Required user attributes.
+     * @return Users with requested attributes.
+     * @throws CharonException         Error while listing users.
+     * @throws NotImplementedException Operation note implemented.
+     * @throws BadRequestException     Bad request.
      */
     default UsersGetResponse listUsersWithGET(Node node, Integer startIndex, Integer count, String sortBy,
-                        String sortOrder, String domainName, Map<String, Boolean> requiredAttributes)
+                                         String sortOrder, String domainName, Map<String, Boolean> requiredAttributes)
+            throws CharonException, NotImplementedException, BadRequestException {
+
+        return null;
+    }
+
+    /**
+     * List users with Get using cursor pagination.
+     *
+     * @param node               Tree node built based on the filtering conditions.
+     * @param cursor             Cursor value for pagination and the Pagination direction.
+     * @param count              Count.
+     * @param sortBy             Sort by.
+     * @param sortOrder          Sort order.
+     * @param domainName         Domain name.
+     * @param requiredAttributes Required user attributes.
+     * @return Users with requested attributes.
+     * @throws CharonException         Error while listing users.
+     * @throws NotImplementedException Operation note implemented.
+     * @throws BadRequestException     Bad request.
+     */
+    default UsersGetResponse listUsersWithGET(Node node, Cursor cursor, Integer count, String sortBy, String sortOrder,
+                                              String domainName, Map<String, Boolean> requiredAttributes)
             throws CharonException, NotImplementedException, BadRequestException {
 
         return null;
@@ -86,7 +109,7 @@ default UsersGetResponse listUsersWithGET(Node node, Integer startIndex, Integer
      */
     @Deprecated
     default UsersGetResponse listUsersWithGET(Node node, int startIndex, int count, String sortBy, String sortOrder,
-            String domainName, Map<String, Boolean> requiredAttributes)
+                                              String domainName, Map<String, Boolean> requiredAttributes)
             throws CharonException, NotImplementedException, BadRequestException {
 
         return null;
@@ -188,7 +211,7 @@ public Group updateGroup(Group oldGroup, Group newGroup, Map<String, Boolean> re
      *
      * @param oldGroup
      * @param newGroup
-     *
+     * 
      * @throws NotImplementedException
      * @throws BadRequestException
      * @throws CharonException

modules/charon-core/src/main/java/org/wso2/charon3/core/objects/ListedResource.java

@@ -130,6 +130,42 @@ public void setStartIndex(int startIndex) {
         }
     }
 
+    /**
+     * Setting the next cursor as an SCIM attribute.
+     *
+     * @param nextCursor  The base64 encoded JSON string, made up of the cursor value and the pagination direction.
+     */
+    public void setNextCursor(String nextCursor) {
+
+        if (!isAttributeExist(SCIMConstants.ListedResourceSchemaConstants.NEXT_CURSOR)) {
+            SimpleAttribute nextCursorAttribute =
+                    new SimpleAttribute(SCIMConstants.ListedResourceSchemaConstants.NEXT_CURSOR, nextCursor);
+            attributeList.put(SCIMConstants.ListedResourceSchemaConstants.NEXT_CURSOR, nextCursorAttribute);
+        } else {
+            SimpleAttribute nextCursorAttribute = ((SimpleAttribute) attributeList
+                    .get(SCIMConstants.ListedResourceSchemaConstants.NEXT_CURSOR));
+            nextCursorAttribute.setValue(nextCursor);
+        }
+    }
+
+    /**
+     * Setting the previous cursor as an SCIM attribute.
+     *
+     * @param previousCursor  The base64 encoded JSON string, made up of the cursor value and the pagination direction.
+     */
+    public void setPreviousCursor(String previousCursor) {
+
+        if (!isAttributeExist(SCIMConstants.ListedResourceSchemaConstants.PREVIOUS_CURSOR)) {
+            SimpleAttribute prevCursorAttribute =
+                    new SimpleAttribute(SCIMConstants.ListedResourceSchemaConstants.PREVIOUS_CURSOR, previousCursor);
+            attributeList.put(SCIMConstants.ListedResourceSchemaConstants.PREVIOUS_CURSOR, prevCursorAttribute);
+        } else {
+            SimpleAttribute previousCursorAttribute = ((SimpleAttribute) attributeList
+                    .get(SCIMConstants.ListedResourceSchemaConstants.PREVIOUS_CURSOR));
+            previousCursorAttribute.setValue(previousCursor);
+        }
+    }
+
     /**
      * set the listed resources
      *

modules/charon-core/src/main/java/org/wso2/charon3/core/objects/plainobjects/Cursor.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2022, WSO2 Inc. (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.charon3.core.objects.plainobjects;
+
+/**
+ * This class representation can be used to create a cursor type object which carries direction and cursor value
+ * to be used in cursor-based pagination.
+ */
+public class Cursor {
+
+    private String cursorValue;
+    private String direction;
+
+    public Cursor (String cursorVal, String direction) {
+        this.cursorValue = cursorVal;
+        this.direction = direction;
+    }
+
+    public String getCursorValue() {
+
+        return cursorValue;
+    }
+
+    public void setCursorValue(String cursorValue) {
+
+        this.cursorValue = cursorValue;
+    }
+
+    public String getDirection() {
+
+        return direction;
+    }
+
+    public void setDirection(String direction) {
+
+        this.direction = direction;
+    }
+}

modules/charon-core/src/main/java/org/wso2/charon3/core/objects/plainobjects/UsersGetResponse.java

@@ -22,12 +22,20 @@
 import java.util.List;
 
 /**
+<<<<<<< HEAD
  * This class representation can be used to create a UsersGetResponse type object which carries the total number of
  * users identified from the filter and the list of users returned for this request.
+=======
+ * This class representation can be used to create a UserGetResponse type object which carries the list of users,
+ * total number of users and optionally the previous and next cursor value.
+ *
+>>>>>>> Cursor based pagination for scim resources.
  */
 public class UsersGetResponse {
 
     private int totalUsers;
+    private String nextCursor;
+    private String previousCursor;
     private List<User> users;
 
     /**
@@ -39,6 +47,17 @@ public UsersGetResponse(int totalUsers, List<User> users) {
         this.users = users;
     }
 
+    /**
+     * Constructor used to build a response object when using cursor pagination.
+     */
+    public UsersGetResponse(int totalUsers, String nextCursor, String previousCursor, List<User> users) {
+
+        this.totalUsers = totalUsers;
+        this.nextCursor = nextCursor;
+        this.previousCursor = previousCursor;
+        this.users = users;
+    }
+
     public int getTotalUsers() {
 
         return totalUsers;
@@ -48,6 +67,21 @@ public void setTotalUsers(int totalUsers) {
 
         this.totalUsers = totalUsers;
     }
+    public String getNextCursor() {
+        return nextCursor;
+    }
+
+    public void setNextCursor(String nextCursor) {
+        this.nextCursor = nextCursor;
+    }
+
+    public String getPrevCursor() {
+        return previousCursor;
+    }
+
+    public void setPrevCursor(String prevCursor) {
+        this.previousCursor = prevCursor;
+    }
 
     public List<User> getUsers() {
 

modules/charon-core/src/main/java/org/wso2/charon3/core/protocol/SCIMResponse.java

@@ -28,6 +28,7 @@ public class SCIMResponse {
     //If there are any HTTP header parameters to be set in response other than response code,
     protected Map<String, String> headerParamMap;
 
+
     /*
      * Constructor with three params
      *

modules/charon-core/src/main/java/org/wso2/charon3/core/protocol/endpoints/ResourceManager.java

@@ -78,24 +78,44 @@ public interface ResourceManager {
      */
     @Deprecated
     SCIMResponse listWithGET(UserManager userManager, String filter, int startIndex, int count, String sortBy,
-            String sortOrder, String domainName, String attributes, String excludeAttributes);
+                             String sortOrder, String domainName, String attributes, String excludeAttributes);
 
     /*
-     * Get resources
-     *
-     * @param userManager       User manager
-     * @param filter            Filter to be executed
-     * @param startIndexInt     Starting index value of the filter
-     * @param countInt          Number of required results
-     * @param sortBy            SortBy
-     * @param sortOrder         Sorting order
-     * @param domainName        Domain name
-     * @param attributes        Attributes in the request
-     * @param excludeAttributes Exclude attributes
-     * @return SCIM response
+     * Get resources.
+     *
+     * @param userManager       User manager.
+     * @param filter            Filter to be executed.
+     * @param startIndexInt     Starting index value of the filter.
+     * @param countInt          Number of required results.
+     * @param sortBy            SortBy.
+     * @param sortOrder         Sorting order.
+     * @param domainName        Domain name.
+     * @param attributes        Attributes in the request.
+     * @param excludeAttributes Exclude attributes.
+     * @return SCIM response.
      */
     default SCIMResponse listWithGET(UserManager userManager, String filter, Integer startIndexInt, Integer countInt,
-            String sortBy, String sortOrder, String domainName, String attributes, String excludeAttributes) {
+                String sortBy, String sortOrder, String domainName, String attributes, String excludeAttributes) {
+
+        return null;
+    }
+
+    /*
+     * Get resources with cursor.
+     *
+     * @param userManager       User manager.
+     * @param filter            Filter to be executed.
+     * @param cursor            Cursor value for pagination.
+     * @param countInt          Number of required results.
+     * @param sortBy            SortBy.
+     * @param sortOrder         Sorting order.
+     * @param domainName        Domain name.
+     * @param attributes        Attributes in the request.
+     * @param excludeAttributes Exclude attributes.
+     * @return SCIM response.
+     */
+    default SCIMResponse listWithGET(UserManager userManager, String filter, String cursor, Integer countInt,
+                  String sortBy, String sortOrder, String domainName, String attributes, String excludeAttributes) {
 
         return null;
     }