ACS-4028 GET Category by id (#1601)

* ACS-4028 Get category by id (#1591)

* ACS-4028: Get category by id endpoint.

* ACS-4028: Get category by id endpoint.

* ACS-4028: Get category by id endpoint - integration TAS tests.

* ACS-4028: Get category by id endpoint - refactoring.

* ACS-4028: Adding test to test suite.

* ACS-4028: Fixes after code review.

* ACS-4019: Removing redundant test group.

packaging/tests/tas-restapi/src/main/java/org/alfresco/rest/model/RestCategoryBodyModel.java

@@ -0,0 +1,43 @@
+package org.alfresco.rest.model;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import org.alfresco.rest.core.IRestModel;
+import org.alfresco.utility.model.TestModel;
+
+/**
+ * Generated by 'mpichura' on '2022-12-01 13:41' from 'Alfresco Content Services REST API' swagger file 
+ * Generated from 'Alfresco Content Services REST API' swagger file
+ * Base Path {@linkplain /alfresco/api/-default-/public/alfresco/versions/1}
+ */
+public class RestCategoryBodyModel extends TestModel implements IRestModel<RestCategoryBodyModel>
+{
+    @JsonProperty(value = "entry")
+    RestCategoryBodyModel model;
+
+    @Override
+    public RestCategoryBodyModel onModel()
+    {
+        return model;
+    }
+
+    /**
+    The name of the category.
+
+This must be unique within the parent category.
+
+    */	        
+
+    @JsonProperty(required = true)    
+    private String name;	    
+
+    public String getName()
+    {
+        return this.name;
+    }
+
+    public void setName(String name)
+    {
+        this.name = name;
+    }				
+}
+ 

packaging/tests/tas-restapi/src/main/java/org/alfresco/rest/model/RestCategoryLinkBodyModel.java

@@ -0,0 +1,40 @@
+package org.alfresco.rest.model;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import org.alfresco.rest.core.IRestModel;
+import org.alfresco.utility.model.TestModel;
+
+/**
+ * Generated by 'mpichura' on '2022-12-01 13:41' from 'Alfresco Content Services REST API' swagger file 
+ * Generated from 'Alfresco Content Services REST API' swagger file
+ * Base Path {@linkplain /alfresco/api/-default-/public/alfresco/versions/1}
+ */
+public class RestCategoryLinkBodyModel extends TestModel implements IRestModel<RestCategoryLinkBodyModel>
+{
+    @JsonProperty(value = "entry")
+    RestCategoryLinkBodyModel model;
+
+    @Override
+    public RestCategoryLinkBodyModel onModel()
+    {
+        return model;
+    }
+
+    /**
+    The identifier of the category.
+    */	        
+
+    @JsonProperty(required = true)    
+    private String id;	    
+
+    public String getId()
+    {
+        return this.id;
+    }
+
+    public void setId(String id)
+    {
+        this.id = id;
+    }				
+}
+ 

packaging/tests/tas-restapi/src/main/java/org/alfresco/rest/model/RestCategoryModel.java

@@ -0,0 +1,104 @@
+package org.alfresco.rest.model;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import org.alfresco.rest.core.IRestModel;
+import org.alfresco.utility.model.TestModel;
+
+/**
+ * Generated by 'mpichura' on '2022-12-01 13:41' from 'Alfresco Content Services REST API' swagger file 
+ * Generated from 'Alfresco Content Services REST API' swagger file
+ * Base Path {@linkplain /alfresco/api/-default-/public/alfresco/versions/1}
+ */
+public class RestCategoryModel extends TestModel implements IRestModel<RestCategoryModel>
+{
+    @JsonProperty(value = "entry")
+    RestCategoryModel model;
+
+    @Override
+    public RestCategoryModel onModel()
+    {
+        return model;
+    }
+
+    /**
+    The identifier for the category.
+    */	        
+
+    @JsonProperty(required = true)    
+    private String id;	    
+    /**
+    The name of the category.
+
+This must be unique within the parent category.
+
+    */	        
+
+    @JsonProperty(required = true)    
+    private String name;	    
+    /**
+    The id of the parent category (or -root- if this is a top level category).
+    */	        
+
+    private String parentId;	    
+    /**
+    True if the category has at least one child category.
+    */	        
+
+    private boolean hasChildren;	    
+    /**
+    The number of nodes that are assigned to this category.
+    */	        
+
+    private long count;
+
+    public String getId()
+    {
+        return this.id;
+    }
+
+    public void setId(String id)
+    {
+        this.id = id;
+    }				
+
+    public String getName()
+    {
+        return this.name;
+    }
+
+    public void setName(String name)
+    {
+        this.name = name;
+    }				
+
+    public String getParentId()
+    {
+        return this.parentId;
+    }
+
+    public void setParentId(String parentId)
+    {
+        this.parentId = parentId;
+    }				
+
+    public boolean getHasChildren()
+    {
+        return this.hasChildren;
+    }
+
+    public void setHasChildren(boolean hasChildren)
+    {
+        this.hasChildren = hasChildren;
+    }				
+
+    public long getCount()
+    {
+        return this.count;
+    }
+
+    public void setCount(long count)
+    {
+        this.count = count;
+    }				
+}
+ 

packaging/tests/tas-restapi/src/main/java/org/alfresco/rest/requests/Categories.java

@@ -0,0 +1,55 @@
+/*-
+ * #%L
+ * alfresco-tas-restapi
+ * %%
+ * Copyright (C) 2005 - 2022 Alfresco Software Limited
+ * %%
+ * This file is part of the Alfresco software.
+ * If the software was purchased under a paid Alfresco license, the terms of
+ * the paid license agreement will prevail.  Otherwise, the software is
+ * provided under the following open source license terms:
+ *
+ * Alfresco is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Alfresco is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
+ * #L%
+ */
+package org.alfresco.rest.requests;
+
+import org.alfresco.rest.core.RestRequest;
+import org.alfresco.rest.core.RestWrapper;
+import org.alfresco.rest.model.RestCategoryModel;
+import org.springframework.http.HttpMethod;
+
+public class Categories extends ModelRequest<Categories>
+{
+    private RestCategoryModel category;
+
+    public Categories(RestWrapper restWrapper, RestCategoryModel category)
+    {
+        super(restWrapper);
+        this.category = category;
+    }
+
+    /**
+     * Retrieves a category with ID using GET call on using GET call on "/tags/{tagId}"
+     *
+     * @return
+     */
+    public RestCategoryModel getCategory()
+    {
+        RestRequest request = RestRequest
+                .simpleRequest(HttpMethod.GET, "categories/{categoryId}?{parameters}", category.getId(), restWrapper.getParameters());
+        return restWrapper.processModel(RestCategoryModel.class, request);
+    }
+
+}

packaging/tests/tas-restapi/src/main/java/org/alfresco/rest/requests/coreAPI/RestCoreAPI.java

@@ -26,12 +26,14 @@
 package org.alfresco.rest.requests.coreAPI;
 
 import org.alfresco.rest.core.RestWrapper;
+import org.alfresco.rest.model.RestCategoryModel;
 import org.alfresco.rest.model.RestDownloadsModel;
 import org.alfresco.rest.model.RestSiteModelsCollection;
 import org.alfresco.rest.model.RestTagModel;
 import org.alfresco.rest.model.RestTagModelsCollection;
 import org.alfresco.rest.requests.Actions;
 import org.alfresco.rest.requests.Audit;
+import org.alfresco.rest.requests.Categories;
 import org.alfresco.rest.requests.ContentStorageInformation;
 import org.alfresco.rest.requests.Downloads;
 import org.alfresco.rest.requests.Groups;
@@ -184,6 +186,12 @@ public class RestCoreAPI extends ModelRequest<RestCoreAPI>
     {
         return new Tags(tag, restWrapper).getTag();
     }
+
+
+    public Categories usingCategory(RestCategoryModel categoryModel)
+    {
+        return new Categories(restWrapper, categoryModel);
+    }
     
     public Queries usingQueries()
     {

packaging/tests/tas-restapi/src/test/java/org/alfresco/rest/categories/GetCategoriesTests.java

@@ -0,0 +1,83 @@
+/*
+ * #%L
+ * Alfresco Remote API
+ * %%
+ * Copyright (C) 2005 - 2022 Alfresco Software Limited
+ * %%
+ * This file is part of the Alfresco software.
+ * If the software was purchased under a paid Alfresco license, the terms of
+ * the paid license agreement will prevail.  Otherwise, the software is
+ * provided under the following open source license terms:
+ *
+ * Alfresco is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Alfresco is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
+ * #L%
+ */
+
+package org.alfresco.rest.categories;
+
+import static org.alfresco.utility.report.log.Step.STEP;
+import static org.springframework.http.HttpStatus.BAD_REQUEST;
+import static org.springframework.http.HttpStatus.NOT_FOUND;
+
+import org.alfresco.rest.RestTest;
+import org.alfresco.rest.model.RestCategoryModel;
+import org.alfresco.utility.model.FolderModel;
+import org.alfresco.utility.model.SiteModel;
+import org.alfresco.utility.model.TestGroup;
+import org.alfresco.utility.model.UserModel;
+import org.testng.annotations.BeforeClass;
+import org.testng.annotations.Test;
+
+public class GetCategoriesTests extends RestTest
+{
+    private UserModel user;
+
+    @BeforeClass(alwaysRun = true)
+    public void dataPreparation() throws Exception
+    {
+        STEP("Create a user");
+        user = dataUser.createRandomTestUser();
+    }
+
+    /**
+     * Check we get an error when passing -root- as category id
+     */
+    @Test(groups = {TestGroup.REST_API})
+    public void testGetCategoryByIdProvidingRootAsId()
+    {
+        STEP("Get category with -root- as id (which does not exist)");
+        final RestCategoryModel rootCategory = new RestCategoryModel();
+        rootCategory.setId("-root-");
+        restClient.authenticateUser(user).withCoreAPI().usingCategory(rootCategory).getCategory();
+        restClient.assertStatusCodeIs(NOT_FOUND);
+    }
+
+    /**
+     * Check we get an error when passing  as category id
+     */
+    @Test(groups = {TestGroup.REST_API})
+    public void testGetCategoryByIdProvidingFolderAsId()
+    {
+        STEP("Create a site and a folder inside it");
+        final SiteModel site = dataSite.usingUser(user).createPublicRandomSite();
+        final FolderModel folder = dataContent.usingUser(user).usingSite(site).createFolder();
+
+        STEP("Get category with folder id passed as id");
+        final RestCategoryModel rootCategory = new RestCategoryModel();
+        rootCategory.setId(folder.getNodeRef());
+        restClient.authenticateUser(user).withCoreAPI().usingCategory(rootCategory).getCategory();
+        restClient.assertStatusCodeIs(BAD_REQUEST);
+    }
+
+}

packaging/tests/tas-restapi/src/test/java/org/alfresco/rest/rules/ReorderRulesTests.java

@@ -26,6 +26,7 @@
 package org.alfresco.rest.rules;
 
 import static java.util.stream.Collectors.toList;
+
 import static org.alfresco.utility.report.log.Step.STEP;
 import static org.springframework.http.HttpStatus.FORBIDDEN;
 import static org.springframework.http.HttpStatus.OK;

packaging/tests/tas-restapi/src/test/resources/test-suites/part3-suite.xml

@@ -16,6 +16,7 @@
             <package name="org.alfresco.rest.trashcan.*"/>
             <package name="org.alfresco.rest.workflow.*"/>
             <package name="org.alfresco.rest.models.*"/>
+            <package name="org.alfresco.rest.categories.*"/>
         </packages>
     </test>
 </suite>

remote-api/src/main/java/org/alfresco/rest/api/Categories.java

@@ -0,0 +1,38 @@
+/*
+ * #%L
+ * Alfresco Remote API
+ * %%
+ * Copyright (C) 2005 - 2022 Alfresco Software Limited
+ * %%
+ * This file is part of the Alfresco software.
+ * If the software was purchased under a paid Alfresco license, the terms of
+ * the paid license agreement will prevail.  Otherwise, the software is
+ * provided under the following open source license terms:
+ *
+ * Alfresco is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Alfresco is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
+ * #L%
+ */
+
+package org.alfresco.rest.api;
+
+import org.alfresco.rest.api.model.Category;
+import org.alfresco.rest.framework.resource.parameters.Parameters;
+import org.alfresco.service.Experimental;
+import org.alfresco.service.cmr.repository.NodeRef;
+
+@Experimental
+public interface Categories
+{
+    Category getCategoryById(String id, Parameters params);
+}

remote-api/src/main/java/org/alfresco/rest/api/categories/CategoriesEntityResource.java

@@ -0,0 +1,61 @@
+/*
+ * #%L
+ * Alfresco Remote API
+ * %%
+ * Copyright (C) 2005 - 2016 Alfresco Software Limited
+ * %%
+ * This file is part of the Alfresco software.
+ * If the software was purchased under a paid Alfresco license, the terms of
+ * the paid license agreement will prevail.  Otherwise, the software is
+ * provided under the following open source license terms:
+ *
+ * Alfresco is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Alfresco is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
+ * #L%
+ */
+package org.alfresco.rest.api.categories;
+
+import javax.servlet.http.HttpServletResponse;
+
+import org.alfresco.rest.api.Categories;
+import org.alfresco.rest.api.model.Category;
+import org.alfresco.rest.framework.WebApiDescription;
+import org.alfresco.rest.framework.core.exceptions.EntityNotFoundException;
+import org.alfresco.rest.framework.resource.EntityResource;
+import org.alfresco.rest.framework.resource.actions.interfaces.EntityResourceAction;
+import org.alfresco.rest.framework.resource.parameters.Parameters;
+
+/**
+ * Entity Resource for Categories
+ *
+ * @author mpichura
+ */
+@EntityResource(name = "categories", title = "Categories")
+public class CategoriesEntityResource implements EntityResourceAction.ReadById<Category>
+{
+    private final Categories categories;
+
+    public CategoriesEntityResource(Categories categories)
+    {
+        this.categories = categories;
+    }
+
+    @WebApiDescription(title = "Get category by its id",
+            description = "Retrieves a category given category node id",
+            successStatus = HttpServletResponse.SC_OK)
+    @Override
+    public Category readById(String id, Parameters parameters) throws EntityNotFoundException
+    {
+        return categories.getCategoryById(id, parameters);
+    }
+}

remote-api/src/main/java/org/alfresco/rest/api/categories/package-info.java

@@ -0,0 +1,30 @@
+/*
+ * #%L
+ * Alfresco Remote API
+ * %%
+ * Copyright (C) 2005 - 2022 Alfresco Software Limited
+ * %%
+ * This file is part of the Alfresco software.
+ * If the software was purchased under a paid Alfresco license, the terms of
+ * the paid license agreement will prevail.  Otherwise, the software is
+ * provided under the following open source license terms:
+ *
+ * Alfresco is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Alfresco is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
+ * #L%
+ */
+@WebApi(name = "alfresco", scope = Api.SCOPE.PUBLIC, version = 1)
+package org.alfresco.rest.api.categories;
+
+import org.alfresco.rest.framework.Api;
+import org.alfresco.rest.framework.WebApi;

remote-api/src/main/java/org/alfresco/rest/api/impl/CategoriesImpl.java

@@ -0,0 +1,93 @@
+/*
+ * #%L
+ * Alfresco Remote API
+ * %%
+ * Copyright (C) 2005 - 2022 Alfresco Software Limited
+ * %%
+ * This file is part of the Alfresco software.
+ * If the software was purchased under a paid Alfresco license, the terms of
+ * the paid license agreement will prevail.  Otherwise, the software is
+ * provided under the following open source license terms:
+ *
+ * Alfresco is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Alfresco is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
+ * #L%
+ */
+
+package org.alfresco.rest.api.impl;
+
+import static org.alfresco.rest.api.Nodes.PATH_ROOT;
+
+import java.util.List;
+
+import org.alfresco.model.ContentModel;
+import org.alfresco.rest.api.Categories;
+import org.alfresco.rest.api.Nodes;
+import org.alfresco.rest.api.model.Category;
+import org.alfresco.rest.api.model.Node;
+import org.alfresco.rest.framework.core.exceptions.InvalidArgumentException;
+import org.alfresco.rest.framework.resource.parameters.Parameters;
+import org.alfresco.service.Experimental;
+import org.alfresco.service.cmr.repository.ChildAssociationRef;
+import org.alfresco.service.cmr.repository.NodeRef;
+import org.alfresco.service.cmr.repository.NodeService;
+import org.alfresco.service.namespace.RegexQNamePattern;
+import org.apache.commons.collections.CollectionUtils;
+
+@Experimental
+public class CategoriesImpl implements Categories
+{
+    static final String NOT_A_VALID_CATEGORY = "Node id does not refer to a valid category";
+
+    private final Nodes nodes;
+    private final NodeService nodeService;
+
+    public CategoriesImpl(Nodes nodes, NodeService nodeService)
+    {
+        this.nodes = nodes;
+        this.nodeService = nodeService;
+    }
+
+    @Override
+    public Category getCategoryById(final String id, final Parameters params)
+    {
+        final NodeRef nodeRef = nodes.validateNode(id);
+        final boolean isCategory = nodes.isSubClass(nodeRef, ContentModel.TYPE_CATEGORY, false);
+        if (!isCategory || isRootCategory(nodeRef))
+        {
+            throw new InvalidArgumentException(NOT_A_VALID_CATEGORY, new String[]{id});
+        }
+        final Node categoryNode = nodes.getNode(nodeRef.getId());
+        final Category category = new Category();
+        category.setId(nodeRef.getId());
+        category.setName(categoryNode.getName());
+        category.setParentId(getParentId(nodeRef));
+        final boolean hasChildren = CollectionUtils
+                .isNotEmpty(nodeService.getChildAssocs(nodeRef, RegexQNamePattern.MATCH_ALL, RegexQNamePattern.MATCH_ALL, false));
+        category.setHasChildren(hasChildren);
+
+        return category;
+    }
+
+    private boolean isRootCategory(final NodeRef nodeRef)
+    {
+        final List<ChildAssociationRef> parentAssocs = nodeService.getParentAssocs(nodeRef);
+        return parentAssocs.stream().anyMatch(pa -> pa.getQName().equals(ContentModel.ASPECT_GEN_CLASSIFIABLE));
+    }
+
+    private String getParentId(final NodeRef nodeRef)
+    {
+        final NodeRef parentRef = nodeService.getPrimaryParent(nodeRef).getParentRef();
+        return isRootCategory(parentRef) ? PATH_ROOT : parentRef.getId();
+    }
+}

remote-api/src/main/java/org/alfresco/rest/api/model/Category.java

@@ -0,0 +1,75 @@
+/*
+ * #%L
+ * Alfresco Remote API
+ * %%
+ * Copyright (C) 2005 - 2022 Alfresco Software Limited
+ * %%
+ * This file is part of the Alfresco software.
+ * If the software was purchased under a paid Alfresco license, the terms of
+ * the paid license agreement will prevail.  Otherwise, the software is
+ * provided under the following open source license terms:
+ *
+ * Alfresco is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Alfresco is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
+ * #L%
+ */
+
+package org.alfresco.rest.api.model;
+
+public class Category
+{
+    private String id;
+    private String name;
+    private String parentId;
+    private boolean hasChildren;
+
+    public String getId()
+    {
+        return id;
+    }
+
+    public void setId(String id)
+    {
+        this.id = id;
+    }
+
+    public String getName()
+    {
+        return name;
+    }
+
+    public void setName(String name)
+    {
+        this.name = name;
+    }
+
+    public String getParentId()
+    {
+        return parentId;
+    }
+
+    public void setParentId(String parentId)
+    {
+        this.parentId = parentId;
+    }
+
+    public boolean getHasChildren()
+    {
+        return hasChildren;
+    }
+
+    public void setHasChildren(boolean hasChildren)
+    {
+        this.hasChildren = hasChildren;
+    }
+}

remote-api/src/main/resources/alfresco/public-rest-context.xml

@@ -828,7 +828,26 @@
             </list>
         </property>
     </bean>
-    
+
+    <bean id="categories" class="org.alfresco.rest.api.impl.CategoriesImpl">
+        <constructor-arg name="nodes" ref="nodes"/>
+        <constructor-arg name="nodeService" ref="NodeService"/>
+    </bean>
+
+    <bean id="Categories" class="org.springframework.aop.framework.ProxyFactoryBean">
+        <property name="proxyInterfaces">
+            <value>org.alfresco.rest.api.Categories</value>
+        </property>
+        <property name="target">
+            <ref bean="categories"/>
+        </property>
+        <property name="interceptorNames">
+            <list>
+                <idref bean="legacyExceptionInterceptor"/>
+            </list>
+        </property>
+    </bean>
+
     <bean id="tags" class="org.alfresco.rest.api.impl.TagsImpl">
         <property name="nodes" ref="nodes" />
         <property name="taggingService" ref="TaggingService" />
@@ -1075,11 +1094,15 @@
     <bean class="org.alfresco.rest.api.people.PersonGroupsRelation">
         <property name="groups" ref="Groups" />
     </bean>
-	
+
+    <bean class="org.alfresco.rest.api.categories.CategoriesEntityResource">
+        <constructor-arg name="categories" ref="Categories"/>
+    </bean>
+
     <bean class="org.alfresco.rest.api.tags.TagsEntityResource">
         <property name="tags" ref="Tags" />
     </bean>
-	
+
     <bean class="org.alfresco.rest.api.people.PersonSitesRelation">
         <property name="sites" ref="Sites" />
     </bean>

remote-api/src/test/java/org/alfresco/rest/api/categories/CategoriesEntityResourceTest.java

@@ -0,0 +1,68 @@
+/*
+ * #%L
+ * Alfresco Remote API
+ * %%
+ * Copyright (C) 2005 - 2022 Alfresco Software Limited
+ * %%
+ * This file is part of the Alfresco software.
+ * If the software was purchased under a paid Alfresco license, the terms of
+ * the paid license agreement will prevail.  Otherwise, the software is
+ * provided under the following open source license terms:
+ *
+ * Alfresco is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Alfresco is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
+ * #L%
+ */
+
+package org.alfresco.rest.api.categories;
+
+import static org.junit.Assert.assertEquals;
+import static org.mockito.BDDMockito.given;
+import static org.mockito.BDDMockito.then;
+
+import org.alfresco.rest.api.Categories;
+import org.alfresco.rest.api.model.Category;
+import org.alfresco.rest.framework.resource.parameters.Parameters;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+
+@RunWith(MockitoJUnitRunner.class)
+public class CategoriesEntityResourceTest
+{
+    private static final String CATEGORY_ID = "category-node-id";
+    @Mock
+    private Categories categoriesMock;
+    @Mock
+    private Category categoryMock;
+    @Mock
+    private Parameters parametersMock;
+
+    @InjectMocks
+    private CategoriesEntityResource objectUnderTest;
+
+    @Test
+    public void testReadCategoryById()
+    {
+        given(categoriesMock.getCategoryById(CATEGORY_ID, parametersMock)).willReturn(categoryMock);
+
+        //when
+        final Category category = objectUnderTest.readById(CATEGORY_ID, parametersMock);
+
+        then(categoriesMock).should().getCategoryById(CATEGORY_ID, parametersMock);
+        then(categoriesMock).shouldHaveNoMoreInteractions();
+        assertEquals(categoryMock, category);
+    }
+}

remote-api/src/test/java/org/alfresco/rest/api/impl/CategoriesImplTest.java

@@ -0,0 +1,201 @@
+/*
+ * #%L
+ * Alfresco Remote API
+ * %%
+ * Copyright (C) 2005 - 2022 Alfresco Software Limited
+ * %%
+ * This file is part of the Alfresco software.
+ * If the software was purchased under a paid Alfresco license, the terms of
+ * the paid license agreement will prevail.  Otherwise, the software is
+ * provided under the following open source license terms:
+ *
+ * Alfresco is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Alfresco is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
+ * #L%
+ */
+
+package org.alfresco.rest.api.impl;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertThrows;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.BDDMockito.given;
+import static org.mockito.BDDMockito.then;
+
+import java.util.Collections;
+import java.util.List;
+
+import org.alfresco.model.ContentModel;
+import org.alfresco.rest.api.Nodes;
+import org.alfresco.rest.api.model.Category;
+import org.alfresco.rest.api.model.Node;
+import org.alfresco.rest.framework.core.exceptions.EntityNotFoundException;
+import org.alfresco.rest.framework.core.exceptions.InvalidArgumentException;
+import org.alfresco.rest.framework.resource.parameters.Parameters;
+import org.alfresco.service.cmr.repository.ChildAssociationRef;
+import org.alfresco.service.cmr.repository.NodeRef;
+import org.alfresco.service.cmr.repository.NodeService;
+import org.alfresco.service.cmr.repository.StoreRef;
+import org.alfresco.service.namespace.RegexQNamePattern;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+
+@RunWith(MockitoJUnitRunner.class)
+public class CategoriesImplTest
+{
+    private static final String CATEGORY_ID = "category-node-id";
+    private static final String CATEGORY_NAME = "categoryName";
+    private static final String PARENT_ID = "parent-node-id";
+    private static final String CAT_ROOT_NODE_ID = "cat-root-node-id";
+
+    @Mock
+    private Nodes nodesMock;
+    @Mock
+    private NodeService nodeServiceMock;
+    @Mock
+    private Parameters parametersMock;
+    @Mock
+    private ChildAssociationRef dummyChildAssociationRefMock;
+    @Mock
+    private ChildAssociationRef categoryChildAssociationRefMock;
+
+    @InjectMocks
+    private CategoriesImpl objectUnderTest;
+
+    @Test
+    public void shouldNotGetRootCategoryById()
+    {
+        final NodeRef categoryRootNodeRef = new NodeRef(StoreRef.STORE_REF_WORKSPACE_SPACESSTORE, CAT_ROOT_NODE_ID);
+        given(nodesMock.validateNode(CAT_ROOT_NODE_ID)).willReturn(categoryRootNodeRef);
+        given(nodesMock.isSubClass(categoryRootNodeRef, ContentModel.TYPE_CATEGORY, false)).willReturn(true);
+        given(categoryChildAssociationRefMock.getQName()).willReturn(ContentModel.ASPECT_GEN_CLASSIFIABLE);
+        given(nodeServiceMock.getParentAssocs(categoryRootNodeRef)).willReturn(List.of(categoryChildAssociationRefMock));
+
+        //when
+        assertThrows(InvalidArgumentException.class, () -> objectUnderTest.getCategoryById(CAT_ROOT_NODE_ID, parametersMock));
+
+        then(nodesMock).should().validateNode(CAT_ROOT_NODE_ID);
+        then(nodesMock).should().isSubClass(categoryRootNodeRef, ContentModel.TYPE_CATEGORY, false);
+        then(nodesMock).shouldHaveNoMoreInteractions();
+        then(nodeServiceMock).should().getParentAssocs(categoryRootNodeRef);
+        then(nodeServiceMock).shouldHaveNoMoreInteractions();
+    }
+
+    @Test
+    public void testGetCategoryById_withChildren()
+    {
+        final NodeRef categoryNodeRef = new NodeRef(StoreRef.STORE_REF_WORKSPACE_SPACESSTORE, CATEGORY_ID);
+        given(nodesMock.validateNode(CATEGORY_ID)).willReturn(categoryNodeRef);
+        given(nodesMock.isSubClass(categoryNodeRef, ContentModel.TYPE_CATEGORY, false)).willReturn(true);
+        final Node categoryNode = new Node();
+        categoryNode.setName(CATEGORY_NAME);
+        categoryNode.setNodeId(CATEGORY_ID);
+        final NodeRef parentNodeRef = new NodeRef(StoreRef.STORE_REF_WORKSPACE_SPACESSTORE, PARENT_ID);
+        categoryNode.setParentId(parentNodeRef);
+        given(nodesMock.getNode(CATEGORY_ID)).willReturn(categoryNode);
+        final ChildAssociationRef parentAssoc = new ChildAssociationRef(null, parentNodeRef, null, categoryNodeRef);
+        given(nodeServiceMock.getPrimaryParent(categoryNodeRef)).willReturn(parentAssoc);
+        final List<ChildAssociationRef> dummyChildren = List.of(dummyChildAssociationRefMock);
+        given(nodeServiceMock.getChildAssocs(categoryNodeRef, RegexQNamePattern.MATCH_ALL, RegexQNamePattern.MATCH_ALL, false))
+                .willReturn(dummyChildren);
+        //when
+        final Category category = objectUnderTest.getCategoryById(CATEGORY_ID, parametersMock);
+
+        then(nodesMock).should().validateNode(CATEGORY_ID);
+        then(nodesMock).should().isSubClass(categoryNodeRef, ContentModel.TYPE_CATEGORY, false);
+        then(nodesMock).should().getNode(CATEGORY_ID);
+        then(nodesMock).shouldHaveNoMoreInteractions();
+
+        then(nodeServiceMock).should().getPrimaryParent(categoryNodeRef);
+        then(nodeServiceMock).should().getParentAssocs(parentNodeRef);
+        then(nodeServiceMock).should().getParentAssocs(categoryNodeRef);
+        then(nodeServiceMock).should().getChildAssocs(categoryNodeRef, RegexQNamePattern.MATCH_ALL, RegexQNamePattern.MATCH_ALL, false);
+        then(nodeServiceMock).shouldHaveNoMoreInteractions();
+
+        assertEquals(categoryNode.getName(), category.getName());
+        assertEquals(CATEGORY_ID, category.getId());
+        assertEquals(PARENT_ID, category.getParentId());
+        assertTrue(category.getHasChildren());
+    }
+
+    @Test
+    public void testGetCategoryById_withoutChildren()
+    {
+        final NodeRef categoryNodeRef = new NodeRef(StoreRef.STORE_REF_WORKSPACE_SPACESSTORE, CATEGORY_ID);
+        given(nodesMock.validateNode(CATEGORY_ID)).willReturn(categoryNodeRef);
+        given(nodesMock.isSubClass(categoryNodeRef, ContentModel.TYPE_CATEGORY, false)).willReturn(true);
+        final Node categoryNode = new Node();
+        categoryNode.setName(CATEGORY_NAME);
+        categoryNode.setNodeId(CATEGORY_ID);
+        final NodeRef parentNodeRef = new NodeRef(StoreRef.STORE_REF_WORKSPACE_SPACESSTORE, PARENT_ID);
+        categoryNode.setParentId(parentNodeRef);
+        given(nodesMock.getNode(CATEGORY_ID)).willReturn(categoryNode);
+        final ChildAssociationRef parentAssoc = new ChildAssociationRef(null, parentNodeRef, null, categoryNodeRef);
+        given(nodeServiceMock.getPrimaryParent(categoryNodeRef)).willReturn(parentAssoc);
+        given(nodeServiceMock.getChildAssocs(categoryNodeRef, RegexQNamePattern.MATCH_ALL, RegexQNamePattern.MATCH_ALL, false))
+                .willReturn(Collections.emptyList());
+        //when
+        final Category category = objectUnderTest.getCategoryById(CATEGORY_ID, parametersMock);
+
+        then(nodesMock).should().validateNode(CATEGORY_ID);
+        then(nodesMock).should().isSubClass(categoryNodeRef, ContentModel.TYPE_CATEGORY, false);
+        then(nodesMock).should().getNode(CATEGORY_ID);
+        then(nodesMock).shouldHaveNoMoreInteractions();
+
+        then(nodeServiceMock).should().getPrimaryParent(categoryNodeRef);
+        then(nodeServiceMock).should().getParentAssocs(parentNodeRef);
+        then(nodeServiceMock).should().getParentAssocs(categoryNodeRef);
+        then(nodeServiceMock).should().getChildAssocs(categoryNodeRef, RegexQNamePattern.MATCH_ALL, RegexQNamePattern.MATCH_ALL, false);
+        then(nodeServiceMock).shouldHaveNoMoreInteractions();
+
+        assertEquals(categoryNode.getName(), category.getName());
+        assertEquals(CATEGORY_ID, category.getId());
+        assertEquals(PARENT_ID, category.getParentId());
+        assertFalse(category.getHasChildren());
+    }
+
+    @Test
+    public void testGetCategoryById_notACategory()
+    {
+        final NodeRef categoryNodeRef = new NodeRef(StoreRef.STORE_REF_WORKSPACE_SPACESSTORE, CATEGORY_ID);
+        given(nodesMock.validateNode(CATEGORY_ID)).willReturn(categoryNodeRef);
+        given(nodesMock.isSubClass(categoryNodeRef, ContentModel.TYPE_CATEGORY, false)).willReturn(false);
+
+        //when
+        assertThrows(InvalidArgumentException.class, () -> objectUnderTest.getCategoryById(CATEGORY_ID, parametersMock));
+
+        then(nodesMock).should().validateNode(CATEGORY_ID);
+        then(nodesMock).should().isSubClass(categoryNodeRef, ContentModel.TYPE_CATEGORY, false);
+        then(nodesMock).shouldHaveNoMoreInteractions();
+
+        then(nodeServiceMock).shouldHaveNoInteractions();
+    }
+
+    @Test
+    public void testGetCategoryById_nodeNotExists()
+    {
+        given(nodesMock.validateNode(CATEGORY_ID)).willThrow(EntityNotFoundException.class);
+
+        //when
+        assertThrows(EntityNotFoundException.class, () -> objectUnderTest.getCategoryById(CATEGORY_ID, parametersMock));
+
+        then(nodesMock).should().validateNode(CATEGORY_ID);
+        then(nodesMock).shouldHaveNoMoreInteractions();
+
+        then(nodeServiceMock).shouldHaveNoInteractions();
+    }
+}

repository/src/main/java/org/alfresco/repo/search/impl/AbstractCategoryServiceImpl.java

@@ -32,6 +32,7 @@ import java.util.HashSet;
 import java.util.Iterator;
 import java.util.LinkedList;
 import java.util.List;
+import java.util.Optional;
 import java.util.Set;
 
 import org.alfresco.error.AlfrescoRuntimeException;
@@ -42,6 +43,7 @@ import org.alfresco.query.PagingResults;
 import org.alfresco.repo.search.IndexerAndSearcher;
 import org.alfresco.repo.search.IndexerException;
 import org.alfresco.repo.tenant.TenantService;
+import org.alfresco.service.Experimental;
 import org.alfresco.service.cmr.dictionary.DictionaryService;
 import org.alfresco.service.cmr.repository.ChildAssociationRef;
 import org.alfresco.service.cmr.repository.InvalidNodeRefException;
@@ -50,6 +52,7 @@ import org.alfresco.service.cmr.repository.NodeService;
 import org.alfresco.service.cmr.repository.Path;
 import org.alfresco.service.cmr.repository.StoreRef;
 import org.alfresco.service.cmr.search.CategoryService;
+import org.alfresco.service.cmr.search.CategoryServiceException;
 import org.alfresco.service.cmr.search.LimitBy;
 import org.alfresco.service.cmr.search.ResultSet;
 import org.alfresco.service.cmr.search.ResultSetRow;
@@ -59,6 +62,7 @@ import org.alfresco.service.namespace.NamespacePrefixResolver;
 import org.alfresco.service.namespace.QName;
 import org.alfresco.util.ISO9075;
 import org.alfresco.util.Pair;
+import org.apache.commons.collections.CollectionUtils;
 
 /**
  * Category service implementation
@@ -67,6 +71,9 @@ import org.alfresco.util.Pair;
  */
 public abstract class AbstractCategoryServiceImpl implements CategoryService
 {
+    static final String CATEGORY_ROOT_NODE_NOT_FOUND = "Category root node not found";
+    static final String NODE_WITH_CATEGORY_ROOT_TYPE_NOT_FOUND = "Node with category_root type not found";
+
     protected NodeService nodeService;
     
     protected NodeService publicNodeService;
@@ -538,4 +545,23 @@ public abstract class AbstractCategoryServiceImpl implements CategoryService
     }
 
     public abstract List<Pair<NodeRef, Integer>> getTopCategories(StoreRef storeRef, QName aspectName, int count);
+
+    @Override
+    @Experimental
+    public Optional<NodeRef> getRootCategoryNodeRef(final StoreRef storeRef)
+    {
+        final NodeRef rootNode = nodeService.getRootNode(storeRef);
+        final ChildAssociationRef categoryRoot = nodeService.getChildAssocs(rootNode, Set.of(ContentModel.TYPE_CATEGORYROOT)).stream()
+                .findFirst()
+                .orElseThrow(() -> new CategoryServiceException(NODE_WITH_CATEGORY_ROOT_TYPE_NOT_FOUND));
+        final List<ChildAssociationRef> categoryRootAssocs = nodeService.getChildAssocs(categoryRoot.getChildRef());
+        if (CollectionUtils.isEmpty(categoryRootAssocs))
+        {
+            throw new CategoryServiceException(CATEGORY_ROOT_NODE_NOT_FOUND);
+        }
+        return categoryRootAssocs.stream()
+                .filter(ca -> ca.getQName().equals(ContentModel.ASPECT_GEN_CLASSIFIABLE))
+                .map(ChildAssociationRef::getChildRef)
+                .findFirst();
+    }
 }

repository/src/main/java/org/alfresco/service/cmr/search/CategoryService.java

@@ -1,37 +1,39 @@
-/*
- * #%L
- * Alfresco Repository
- * %%
- * Copyright (C) 2005 - 2016 Alfresco Software Limited
- * %%
- * This file is part of the Alfresco software. 
- * If the software was purchased under a paid Alfresco license, the terms of 
- * the paid license agreement will prevail.  Otherwise, the software is 
- * provided under the following open source license terms:
- * 
- * Alfresco is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Lesser General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- * 
- * Alfresco is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Lesser General Public License for more details.
- * 
- * You should have received a copy of the GNU Lesser General Public License
- * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
- * #L%
- */
+/*
+ * #%L
+ * Alfresco Repository
+ * %%
+ * Copyright (C) 2005 - 2016 Alfresco Software Limited
+ * %%
+ * This file is part of the Alfresco software. 
+ * If the software was purchased under a paid Alfresco license, the terms of 
+ * the paid license agreement will prevail.  Otherwise, the software is 
+ * provided under the following open source license terms:
+ * 
+ * Alfresco is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * Alfresco is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
+ * #L%
+ */
 package org.alfresco.service.cmr.search;
 
 import java.util.Collection;
 import java.util.List;
+import java.util.Optional;
 
 import org.alfresco.api.AlfrescoPublicApi;
 import org.alfresco.query.PagingRequest;
 import org.alfresco.query.PagingResults;
 import org.alfresco.service.Auditable;
+import org.alfresco.service.Experimental;
 import org.alfresco.service.cmr.repository.ChildAssociationRef;
 import org.alfresco.service.cmr.repository.NodeRef;
 import org.alfresco.service.cmr.repository.StoreRef;
@@ -234,10 +236,10 @@ public interface CategoryService
      */
     @Auditable(parameters = {"nodeRef"})
     public void deleteCategory(NodeRef nodeRef);
-    
-   /** 
-    * Get the most polular categories 
-    * 
+
+   /**
+    * Get the most polular categories
+    *
     * @param storeRef StoreRef
     * @param aspectName QName
     * @param count int
@@ -245,4 +247,16 @@ public interface CategoryService
     */
     @Auditable(parameters = {"storeRef", "aspectName", "count"})
     public List<Pair<NodeRef, Integer>> getTopCategories(StoreRef storeRef, QName aspectName, int count);
+
+    /**
+     * Get a root category NodeRef
+     *
+     * @return NodeRef for category root node
+     */
+    @Experimental
+    @Auditable(parameters = {"storeRef"})
+    default Optional<NodeRef> getRootCategoryNodeRef(final StoreRef storeRef)
+    {
+        return Optional.empty();
+    }
 }

repository/src/main/java/org/alfresco/service/cmr/search/CategoryServiceException.java

@@ -0,0 +1,61 @@
+/*
+ * #%L
+ * Alfresco Remote API
+ * %%
+ * Copyright (C) 2005 - 2022 Alfresco Software Limited
+ * %%
+ * This file is part of the Alfresco software.
+ * If the software was purchased under a paid Alfresco license, the terms of
+ * the paid license agreement will prevail.  Otherwise, the software is
+ * provided under the following open source license terms:
+ *
+ * Alfresco is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Alfresco is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
+ * #L%
+ */
+
+package org.alfresco.service.cmr.search;
+
+import org.alfresco.error.AlfrescoRuntimeException;
+
+/**
+ * Category Service Exception Class
+ */
+public class CategoryServiceException extends AlfrescoRuntimeException
+{
+	/**
+	 * Serial version UID
+	 */
+	private static final long serialVersionUID = 3257571687441467958L;
+
+	/**
+	 * Construtor
+	 *
+	 * @param message 	the message string
+	 */
+	public CategoryServiceException(String message)
+	{
+		super(message);
+	}
+
+	/**
+	 * Constructor
+	 *
+	 * @param message	the message string
+	 * @param source	the source exception
+	 */
+	public CategoryServiceException(String message, Throwable source)
+	{
+		super(message, source);
+	}
+}

repository/src/test/java/org/alfresco/repo/search/SearchTestSuite.java

@@ -28,6 +28,7 @@ package org.alfresco.repo.search;
 import org.alfresco.repo.search.impl.parsers.CMISTest;
 import org.alfresco.repo.search.impl.parsers.CMIS_FTSTest;
 import org.alfresco.repo.search.impl.parsers.FTSTest;
+import org.alfresco.repo.search.impl.solr.SolrCategoryServiceImplTest;
 import org.alfresco.repo.search.impl.solr.SolrChildApplicationContextFactoryTest;
 import org.alfresco.repo.search.impl.solr.SolrSubsystemTest;
 import org.alfresco.util.NumericEncodingTest;
@@ -46,7 +47,8 @@ import org.junit.runners.Suite;
     CMISTest.class,
     FTSTest.class,
     SolrChildApplicationContextFactoryTest.class,
-    SolrSubsystemTest.class
+    SolrSubsystemTest.class,
+    SolrCategoryServiceImplTest.class
 })
 
 public class SearchTestSuite

repository/src/test/java/org/alfresco/repo/search/impl/solr/SolrCategoryServiceImplTest.java

@@ -0,0 +1,93 @@
+/*
+ * #%L
+ * Alfresco Remote API
+ * %%
+ * Copyright (C) 2005 - 2022 Alfresco Software Limited
+ * %%
+ * This file is part of the Alfresco software.
+ * If the software was purchased under a paid Alfresco license, the terms of
+ * the paid license agreement will prevail.  Otherwise, the software is
+ * provided under the following open source license terms:
+ *
+ * Alfresco is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Alfresco is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
+ * #L%
+ */
+
+package org.alfresco.repo.search.impl.solr;
+
+import static org.junit.Assert.*;
+import static org.mockito.BDDMockito.given;
+import static org.mockito.BDDMockito.then;
+
+import java.util.List;
+import java.util.Optional;
+import java.util.Set;
+
+import org.alfresco.model.ContentModel;
+import org.alfresco.repo.search.impl.noindex.NoIndexCategoryServiceImpl;
+import org.alfresco.service.cmr.repository.ChildAssociationRef;
+import org.alfresco.service.cmr.repository.NodeRef;
+import org.alfresco.service.cmr.repository.NodeService;
+import org.alfresco.service.cmr.repository.StoreRef;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+
+/**
+ * This test class covers part of the code implemented in abstract class {@link org.alfresco.repo.search.impl.AbstractCategoryServiceImpl}.
+ * That's because abstract class cannot be instantiated and directly tested.
+ */
+@RunWith(MockitoJUnitRunner.class)
+public class SolrCategoryServiceImplTest
+{
+    private static final String PATH_ROOT = "-root-";
+    private static final String CAT_ROOT_NODE_ID = "cat-root-node-id";
+
+    @Mock
+    private NodeService nodeServiceMock;
+    @Mock
+    private ChildAssociationRef categoryRootChildAssociationRefMock;
+    @Mock
+    private ChildAssociationRef categoryChildAssociationRefMock;
+
+    @InjectMocks
+    private NoIndexCategoryServiceImpl objectUnderTest;
+
+    @Test
+    public void testGetRootCategoryNodeRef()
+    {
+        final NodeRef rootNodeRef = new NodeRef(StoreRef.STORE_REF_WORKSPACE_SPACESSTORE, PATH_ROOT);
+        given(nodeServiceMock.getRootNode(StoreRef.STORE_REF_WORKSPACE_SPACESSTORE)).willReturn(rootNodeRef);
+        given(nodeServiceMock.getChildAssocs(rootNodeRef, Set.of(ContentModel.TYPE_CATEGORYROOT)))
+                .willReturn(List.of(categoryRootChildAssociationRefMock));
+        given(categoryChildAssociationRefMock.getQName()).willReturn(ContentModel.ASPECT_GEN_CLASSIFIABLE);
+        final NodeRef categoryRootNodeRef = new NodeRef(StoreRef.STORE_REF_WORKSPACE_SPACESSTORE, CAT_ROOT_NODE_ID);
+        given(categoryChildAssociationRefMock.getChildRef()).willReturn(categoryRootNodeRef);
+        given(nodeServiceMock.getChildAssocs(categoryRootChildAssociationRefMock.getChildRef()))
+                .willReturn(List.of(categoryChildAssociationRefMock));
+
+        //when
+        final Optional<NodeRef> rooCategoryNodeRef = objectUnderTest.getRootCategoryNodeRef(StoreRef.STORE_REF_WORKSPACE_SPACESSTORE);
+
+        then(nodeServiceMock).should().getRootNode(StoreRef.STORE_REF_WORKSPACE_SPACESSTORE);
+        then(nodeServiceMock).should().getChildAssocs(rootNodeRef, Set.of(ContentModel.TYPE_CATEGORYROOT));
+        then(nodeServiceMock).should().getChildAssocs(categoryRootChildAssociationRefMock.getChildRef());
+        then(nodeServiceMock).shouldHaveNoMoreInteractions();
+
+        assertTrue(rooCategoryNodeRef.isPresent());
+        assertEquals(CAT_ROOT_NODE_ID, rooCategoryNodeRef.get().getId());
+    }
+}