diff --git a/.gitignore b/.gitignore
index 8bd3a05..58eaa38 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,4 @@
 /.settings/
 /.classpath
 /.project
+*.iml
\ No newline at end of file
diff --git a/pom.xml b/pom.xml
index e226ef7..a17cc19 100644
--- a/pom.xml
+++ b/pom.xml
@@ -1,215 +1,232 @@
 <?xml version="1.0"?>
-<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
-	<modelVersion>4.0.0</modelVersion>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
 
-	<groupId>li.strolch</groupId>
-	<artifactId>strolch-bookshop</artifactId>
-	<version>0.1.0-SNAPSHOT</version>
-	<packaging>war</packaging>
-	
-	<name>strolch-bookshop</name>
-	<description>Bookshop built on Strolch</description>
-	<inceptionYear>2017</inceptionYear>
+    <groupId>li.strolch</groupId>
+    <artifactId>strolch-bookshop</artifactId>
+    <version>0.1.0-SNAPSHOT</version>
+    <packaging>war</packaging>
 
-	<properties>
-		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-		<maven.build.timestamp.format>yyyy-MM-dd HH:mm:ss</maven.build.timestamp.format>
-		<buildTimestamp>${maven.build.timestamp}</buildTimestamp>
+    <name>strolch-bookshop</name>
+    <description>Bookshop built on Strolch</description>
+    <inceptionYear>2017</inceptionYear>
 
-		<java-version>1.8</java-version>
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <maven.build.timestamp.format>yyyy-MM-dd HH:mm:ss</maven.build.timestamp.format>
+        <buildTimestamp>${maven.build.timestamp}</buildTimestamp>
 
-		<strolch.version>1.6.0-SNAPSHOT</strolch.version>
-		<jersey.version>2.25.1</jersey.version>
-		<jaxrs.api.version>2.0</jaxrs.api.version>
+        <jdk.version>1.8</jdk.version>
 
-		<warFinalName>bookshop</warFinalName>
-		<m2eclipse.wtp.contextRoot>${warFinalName}</m2eclipse.wtp.contextRoot>
-	</properties>
+        <jersey.version>2.25.1</jersey.version>
+        <slf4j.version>1.7.25</slf4j.version>
+        <logback.version>1.2.3</logback.version>
+        <petitparser.version>2.1.0</petitparser.version>
+        <hikaricp.version>2.7.1</hikaricp.version>
+        <postgresql.version>42.1.4</postgresql.version>
+        <gson.version>2.8.2</gson.version>
+        <annotation.version>1.3.1</annotation.version>
+        <javaxmail.version>1.6.0</javaxmail.version>
+        <serverlet.version>3.1.0</serverlet.version>
+        <jaxrs.api.version>2.1</jaxrs.api.version>
 
-	<dependencies>
-		<!-- base -->
-		<dependency>
-			<groupId>org.slf4j</groupId>
-			<artifactId>slf4j-api</artifactId>
-			<version>1.7.25</version>
-		</dependency>
-		<dependency>
-			<groupId>ch.qos.logback</groupId>
-			<artifactId>logback-classic</artifactId>
-			<version>1.2.3</version>
-		</dependency>
+        <junit.version>4.12</junit.version>
+        <hamcrest.version>1.3</hamcrest.version>
+        <mockito.version>2.0.8-beta</mockito.version>
 
-		<!-- strolch -->
-		<dependency>
-			<groupId>li.strolch</groupId>
-			<artifactId>li.strolch.utils</artifactId>
-			<version>${strolch.version}</version>
-		</dependency>
-		<dependency>
-			<groupId>li.strolch</groupId>
-			<artifactId>li.strolch.privilege</artifactId>
-			<version>${strolch.version}</version>
-		</dependency>
-		<dependency>
-			<groupId>li.strolch</groupId>
-			<artifactId>li.strolch.model</artifactId>
-			<version>${strolch.version}</version>
-		</dependency>
-		<dependency>
-			<groupId>li.strolch</groupId>
-			<artifactId>li.strolch.agent</artifactId>
-			<version>${strolch.version}</version>
-		</dependency>
-		<dependency>
-			<groupId>li.strolch</groupId>
-			<artifactId>li.strolch.rest</artifactId>
-			<version>${strolch.version}</version>
-		</dependency>
-		<dependency>
-			<groupId>li.strolch</groupId>
-			<artifactId>li.strolch.service</artifactId>
-			<version>${strolch.version}</version>
-		</dependency>
-		<dependency>
-			<groupId>li.strolch</groupId>
-			<artifactId>li.strolch.testbase</artifactId>
-			<version>${strolch.version}</version>
-			<scope>test</scope>
-		</dependency>
+        <maven-compiler-plugin.version>3.7.0</maven-compiler-plugin.version>
+        <maven-source-plugin.version>3.0.1</maven-source-plugin.version>
+        <maven-jar-plugin.version>3.0.2</maven-jar-plugin.version>
+        <maven-war-plugin.version>3.1.0</maven-war-plugin.version>
 
-		<!-- utils -->
-		<dependency>
-			<groupId>com.github.petitparser.java-petitparser</groupId>
-			<artifactId>petitparser-core</artifactId>
-			<version>2.0.3</version>
-		</dependency>
-		<dependency>
-			<groupId>com.google.code.gson</groupId>
-			<artifactId>gson</artifactId>
-			<version>2.3.1</version>
-		</dependency>
+        <strolch.version>1.6.0-SNAPSHOT</strolch.version>
 
-		<!-- web -->
-		<dependency>
-			<groupId>javax.servlet</groupId>
-			<artifactId>javax.servlet-api</artifactId>
-			<version>3.0.1</version>
-			<scope>provided</scope>
-		</dependency>
-		<dependency>
-			<groupId>javax.ws.rs</groupId>
-			<artifactId>javax.ws.rs-api</artifactId>
-			<version>${jaxrs.api.version}</version>
-		</dependency>
+        <warFinalName>bookshop</warFinalName>
+        <m2eclipse.wtp.contextRoot>${warFinalName}</m2eclipse.wtp.contextRoot>
+    </properties>
 
-		<!-- testing -->
-		<dependency>
-			<groupId>junit</groupId>
-			<artifactId>junit</artifactId>
-			<version>4.11</version>
-			<scope>test</scope>
-		</dependency>
-		<dependency>
-			<groupId>org.hamcrest</groupId>
-			<artifactId>hamcrest-core</artifactId>
-			<version>1.3</version>
-			<scope>test</scope>
-		</dependency>
-		<dependency>
-			<groupId>org.hamcrest</groupId>
-			<artifactId>hamcrest-library</artifactId>
-			<version>1.3</version>
-			<scope>test</scope>
-		</dependency>
-	</dependencies>
+    <dependencies>
 
-	<build>
-		<resources>
-			<!-- filter properties files, and copy the rest -->
-			<resource>
-				<directory>src/main/resources</directory>
-				<filtering>true</filtering>
-				<includes>
-					<include>**/*.properties</include>
-				</includes>
-			</resource>
-			<resource>
-				<directory>src/main/resources</directory>
-				<filtering>false</filtering>
-				<excludes>
-					<exclude>**/*.properties</exclude>
-				</excludes>
-			</resource>
-		</resources>
+        <!-- base -->
+        <dependency>
+            <groupId>org.slf4j</groupId>
+            <artifactId>slf4j-api</artifactId>
+            <version>${slf4j.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>ch.qos.logback</groupId>
+            <artifactId>logback-classic</artifactId>
+            <version>${logback.version}</version>
+            <scope>runtime</scope>
+        </dependency>
 
-		<plugins>
-			<plugin>
-				<groupId>org.apache.maven.plugins</groupId>
-				<artifactId>maven-compiler-plugin</artifactId>
-				<version>3.0</version>
-				<configuration>
-					<source>${java-version}</source>
-					<target>${java-version}</target>
-				</configuration>
-			</plugin>
-			<plugin>
-				<groupId>org.apache.maven.plugins</groupId>
-				<artifactId>maven-war-plugin</artifactId>
-				<version>2.4</version>
-				<configuration>
-					<failOnMissingWebXml>false</failOnMissingWebXml>
-					<warName>${warFinalName}</warName>
-				</configuration>
-			</plugin>
-		</plugins>
-	</build>
+        <!-- strolch -->
+        <dependency>
+            <groupId>li.strolch</groupId>
+            <artifactId>li.strolch.utils</artifactId>
+            <version>${strolch.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>li.strolch</groupId>
+            <artifactId>li.strolch.privilege</artifactId>
+            <version>${strolch.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>li.strolch</groupId>
+            <artifactId>li.strolch.model</artifactId>
+            <version>${strolch.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>li.strolch</groupId>
+            <artifactId>li.strolch.agent</artifactId>
+            <version>${strolch.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>li.strolch</groupId>
+            <artifactId>li.strolch.rest</artifactId>
+            <version>${strolch.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>li.strolch</groupId>
+            <artifactId>li.strolch.service</artifactId>
+            <version>${strolch.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>li.strolch</groupId>
+            <artifactId>li.strolch.testbase</artifactId>
+            <version>${strolch.version}</version>
+            <scope>test</scope>
+        </dependency>
 
-	<repositories>
-		<!-- used by petit-parser -->
-		<repository>
-			<id>jitpack.io</id>
-			<name>snapshots</name>
-			<url>https://jitpack.io</url>
-			<releases>
-				<enabled>true</enabled>
-			</releases>
-			<snapshots>
-				<enabled>true</enabled>
-			</snapshots>
-		</repository>
-	</repositories>
+        <!-- utils -->
+        <dependency>
+            <groupId>com.google.code.gson</groupId>
+            <artifactId>gson</artifactId>
+            <version>${gson.version}</version>
+        </dependency>
 
-	<profiles>
-		<!-- active when building on eitch's machines -->
-		<profile>
-			<id>m2e.eitchpc</id>
-			<activation>
-				<property>
-					<name>user.name</name>
-					<value>eitch</value>
-				</property>
-				<os>
-					<family>unix</family>
-				</os>
-			</activation>
-			<properties>
-				<strolch.env>dev.eitchpc</strolch.env>
-			</properties>
-		</profile>
-		<profile>
-			<id>m2e.eitchmac</id>
-			<activation>
-				<property>
-					<name>user.name</name>
-					<value>eitch</value>
-				</property>
-				<os>
-					<family>mac</family>
-				</os>
-			</activation>
-			<properties>
-				<strolch.env>dev.eitchmac</strolch.env>
-			</properties>
-		</profile>
-	</profiles>
+        <!-- web -->
+        <dependency>
+            <groupId>javax.servlet</groupId>
+            <artifactId>javax.servlet-api</artifactId>
+            <version>${serverlet.version}</version>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>javax.ws.rs</groupId>
+            <artifactId>javax.ws.rs-api</artifactId>
+            <version>${jaxrs.api.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.glassfish.jersey.core</groupId>
+            <artifactId>jersey-common</artifactId>
+            <version>${jersey.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.glassfish.jersey.core</groupId>
+            <artifactId>jersey-server</artifactId>
+            <version>${jersey.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.glassfish.jersey.containers</groupId>
+            <artifactId>jersey-container-servlet</artifactId>
+            <version>${jersey.version}</version>
+        </dependency>
+
+        <!-- testing -->
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>${junit.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.hamcrest</groupId>
+            <artifactId>hamcrest-core</artifactId>
+            <version>${hamcrest.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.hamcrest</groupId>
+            <artifactId>hamcrest-library</artifactId>
+            <version>${hamcrest.version}</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <resources>
+            <!-- filter properties files, and copy the rest -->
+            <resource>
+                <directory>src/main/resources</directory>
+                <filtering>true</filtering>
+                <includes>
+                    <include>**/*.properties</include>
+                </includes>
+            </resource>
+            <resource>
+                <directory>src/main/resources</directory>
+                <filtering>false</filtering>
+                <excludes>
+                    <exclude>**/*.properties</exclude>
+                </excludes>
+            </resource>
+        </resources>
+
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>${maven-compiler-plugin.version}</version>
+                <configuration>
+                    <source>${jdk.version}</source>
+                    <target>${jdk.version}</target>
+                </configuration>
+            </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-war-plugin</artifactId>
+                <version>${maven-war-plugin.version}</version>
+                <configuration>
+                    <failOnMissingWebXml>false</failOnMissingWebXml>
+                    <warName>${warFinalName}</warName>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+
+    <profiles>
+        <!-- active when building on eitch's machines -->
+        <profile>
+            <id>m2e.eitchpc</id>
+            <activation>
+                <property>
+                    <name>user.name</name>
+                    <value>eitch</value>
+                </property>
+                <os>
+                    <family>unix</family>
+                </os>
+            </activation>
+            <properties>
+                <strolch.env>dev.eitchpc</strolch.env>
+            </properties>
+        </profile>
+        <profile>
+            <id>m2e.eitchmac</id>
+            <activation>
+                <property>
+                    <name>user.name</name>
+                    <value>eitch</value>
+                </property>
+                <os>
+                    <family>mac</family>
+                </os>
+            </activation>
+            <properties>
+                <strolch.env>dev.eitchmac</strolch.env>
+            </properties>
+        </profile>
+    </profiles>
 </project>
diff --git a/src/main/java/li/strolch/bookshop/rest/BooksResource.java b/src/main/java/li/strolch/bookshop/rest/BooksResource.java
index d9df346..50e313d 100644
--- a/src/main/java/li/strolch/bookshop/rest/BooksResource.java
+++ b/src/main/java/li/strolch/bookshop/rest/BooksResource.java
@@ -1,42 +1,34 @@
 package li.strolch.bookshop.rest;
 
-import java.util.List;
-
 import javax.servlet.http.HttpServletRequest;
-import javax.ws.rs.DELETE;
-import javax.ws.rs.GET;
-import javax.ws.rs.POST;
-import javax.ws.rs.PUT;
-import javax.ws.rs.Path;
-import javax.ws.rs.PathParam;
-import javax.ws.rs.Produces;
-import javax.ws.rs.QueryParam;
+import javax.ws.rs.*;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
 import javax.ws.rs.core.Response;
 import javax.ws.rs.core.Response.Status;
+import java.util.List;
 
 import com.google.gson.JsonObject;
 import com.google.gson.JsonParser;
-
 import li.strolch.bookshop.BookShopConstants;
 import li.strolch.bookshop.query.BooksQuery;
 import li.strolch.bookshop.service.CreateBookService;
 import li.strolch.bookshop.service.RemoveBookService;
 import li.strolch.bookshop.service.UpdateBookService;
 import li.strolch.model.Resource;
-import li.strolch.model.json.StrolchElementToJsonVisitor;
+import li.strolch.model.json.StrolchRootElementToJsonVisitor;
 import li.strolch.model.query.NameSelection;
 import li.strolch.model.query.OrSelection;
 import li.strolch.model.query.ParameterSelection;
 import li.strolch.model.query.ResourceQuery;
+import li.strolch.model.visitor.ResourceVisitor;
 import li.strolch.persistence.api.StrolchTransaction;
 import li.strolch.privilege.model.Certificate;
 import li.strolch.rest.RestfulStrolchComponent;
 import li.strolch.rest.StrolchRestfulConstants;
 import li.strolch.rest.helper.ResponseUtil;
-import li.strolch.rest.util.JsonServiceArgument;
-import li.strolch.rest.util.JsonServiceResult;
+import li.strolch.service.JsonServiceArgument;
+import li.strolch.service.JsonServiceResult;
 import li.strolch.service.StringServiceArgument;
 import li.strolch.service.api.ServiceHandler;
 import li.strolch.service.api.ServiceResult;
@@ -62,17 +54,16 @@ public class BooksResource {
 		try (StrolchTransaction tx = RestfulStrolchComponent.getInstance().openTx(cert, getClass())) {
 
 			// prepare the query
-			ResourceQuery<JsonObject> query = new BooksQuery<JsonObject>() //
-					// set transformation to JSON
-					.setVisitor(new StrolchElementToJsonVisitor().flat());
+			ResourceQuery<Resource> query = new BooksQuery<>();
 
 			// prepare selections
 			if (StringHelper.isEmpty(queryS)) {
 				query.withAny();
 			} else {
 				OrSelection or = new OrSelection();
-				or.with(ParameterSelection.stringSelection(BookShopConstants.BAG_PARAMETERS,
-						BookShopConstants.PARAM_DESCRIPTION, queryS, StringMatchMode.ci()));
+				or.with(ParameterSelection
+						.stringSelection(BookShopConstants.BAG_PARAMETERS, BookShopConstants.PARAM_DESCRIPTION, queryS,
+								StringMatchMode.ci()));
 				or.with(new NameSelection(queryS, StringMatchMode.ci()));
 
 				// add selections
@@ -80,13 +71,15 @@ public class BooksResource {
 			}
 
 			// perform the query
-			List<JsonObject> books = tx.doQuery(query);
+			List<Resource> books = tx.doQuery(query);
 
 			// perform paging
-			Paging<JsonObject> page = Paging.asPage(books, offset, limit);
+			Paging<Resource> paging = Paging.asPage(books, offset, limit);
+			List<Resource> page = paging.getPage();
 
-			// return result
-			return ResponseUtil.toResponse(StrolchRestfulConstants.DATA, page.getPage());
+			// return result, transforming to JSON
+			ResourceVisitor<JsonObject> visitor = new StrolchRootElementToJsonVisitor().flat().asResourceVisitor();
+			return ResponseUtil.listToResponse(StrolchRestfulConstants.DATA, page, a -> a.accept(visitor));
 		}
 	}
 
@@ -107,7 +100,7 @@ public class BooksResource {
 				return ResponseUtil.toResponse(Status.NOT_FOUND, "Book " + id + " does not exist!");
 
 			// transform to JSON
-			JsonObject bookJ = book.accept(new StrolchElementToJsonVisitor().flat());
+			JsonObject bookJ = book.accept(new StrolchRootElementToJsonVisitor().flat());
 
 			// return
 			return ResponseUtil.toResponse(StrolchRestfulConstants.DATA, bookJ);
diff --git a/src/main/java/li/strolch/bookshop/service/CreateBookService.java b/src/main/java/li/strolch/bookshop/service/CreateBookService.java
index 49f56b1..6819639 100644
--- a/src/main/java/li/strolch/bookshop/service/CreateBookService.java
+++ b/src/main/java/li/strolch/bookshop/service/CreateBookService.java
@@ -1,15 +1,15 @@
 package li.strolch.bookshop.service;
 
-import com.google.gson.JsonObject;
+import static li.strolch.report.ReportConstants.BAG_RELATIONS;
 
+import com.google.gson.JsonObject;
 import li.strolch.bookshop.BookShopConstants;
 import li.strolch.model.Resource;
 import li.strolch.model.json.FromFlatJsonVisitor;
-import li.strolch.model.json.StrolchElementToJsonVisitor;
-import li.strolch.persistence.api.AddResourceCommand;
+import li.strolch.model.json.StrolchRootElementToJsonVisitor;
 import li.strolch.persistence.api.StrolchTransaction;
-import li.strolch.rest.util.JsonServiceArgument;
-import li.strolch.rest.util.JsonServiceResult;
+import li.strolch.service.JsonServiceArgument;
+import li.strolch.service.JsonServiceResult;
 import li.strolch.service.api.AbstractService;
 
 public class CreateBookService extends AbstractService<JsonServiceArgument, JsonServiceResult> {
@@ -37,19 +37,17 @@ public class CreateBookService extends AbstractService<JsonServiceArgument, Json
 			book = tx.getResourceTemplate(BookShopConstants.TYPE_BOOK);
 
 			// map all values from the JSON object into the new book element
-			new FromFlatJsonVisitor().visit(book, arg.jsonElement.getAsJsonObject());
+			book.accept(new FromFlatJsonVisitor(arg.jsonElement.getAsJsonObject()).ignoreBag(BAG_RELATIONS));
 
-			// add command to store the resource
-			AddResourceCommand cmd = new AddResourceCommand(getContainer(), tx);
-			cmd.setResource(book);
-			tx.addCommand(cmd);
+			// save changes
+			tx.add(book);
 
 			// notify the TX that it should commit on close
 			tx.commitOnClose();
 		}
 
 		// map the return value to JSON
-		JsonObject result = book.accept(new StrolchElementToJsonVisitor().flat());
+		JsonObject result = book.accept(new StrolchRootElementToJsonVisitor().flat());
 
 		// and return the result
 		return new JsonServiceResult(result);
diff --git a/src/main/java/li/strolch/bookshop/service/RemoveBookService.java b/src/main/java/li/strolch/bookshop/service/RemoveBookService.java
index 774c48a..a3c06b8 100644
--- a/src/main/java/li/strolch/bookshop/service/RemoveBookService.java
+++ b/src/main/java/li/strolch/bookshop/service/RemoveBookService.java
@@ -2,7 +2,6 @@ package li.strolch.bookshop.service;
 
 import li.strolch.bookshop.BookShopConstants;
 import li.strolch.model.Resource;
-import li.strolch.persistence.api.RemoveResourceCommand;
 import li.strolch.persistence.api.StrolchTransaction;
 import li.strolch.service.StringServiceArgument;
 import li.strolch.service.api.AbstractService;
@@ -31,10 +30,8 @@ public class RemoveBookService extends AbstractService<StringServiceArgument, Se
 			// get the existing book
 			Resource book = tx.getResourceBy(BookShopConstants.TYPE_BOOK, arg.value, true);
 
-			// add command to remove the resource
-			RemoveResourceCommand cmd = new RemoveResourceCommand(getContainer(), tx);
-			cmd.setResource(book);
-			tx.addCommand(cmd);
+			// save changes
+			tx.remove(book);
 
 			// notify the TX that it should commit on close
 			tx.commitOnClose();
diff --git a/src/main/java/li/strolch/bookshop/service/UpdateBookService.java b/src/main/java/li/strolch/bookshop/service/UpdateBookService.java
index 17df92c..e5243b3 100644
--- a/src/main/java/li/strolch/bookshop/service/UpdateBookService.java
+++ b/src/main/java/li/strolch/bookshop/service/UpdateBookService.java
@@ -1,16 +1,16 @@
 package li.strolch.bookshop.service;
 
-import com.google.gson.JsonObject;
+import static li.strolch.report.ReportConstants.BAG_RELATIONS;
 
+import com.google.gson.JsonObject;
 import li.strolch.bookshop.BookShopConstants;
 import li.strolch.model.Resource;
 import li.strolch.model.Tags.Json;
 import li.strolch.model.json.FromFlatJsonVisitor;
-import li.strolch.model.json.StrolchElementToJsonVisitor;
+import li.strolch.model.json.StrolchRootElementToJsonVisitor;
 import li.strolch.persistence.api.StrolchTransaction;
-import li.strolch.persistence.api.UpdateResourceCommand;
-import li.strolch.rest.util.JsonServiceArgument;
-import li.strolch.rest.util.JsonServiceResult;
+import li.strolch.service.JsonServiceArgument;
+import li.strolch.service.JsonServiceResult;
 import li.strolch.service.api.AbstractService;
 import li.strolch.utils.dbc.DBC;
 
@@ -43,19 +43,17 @@ public class UpdateBookService extends AbstractService<JsonServiceArgument, Json
 			book = tx.getResourceBy(BookShopConstants.TYPE_BOOK, arg.objectId, true);
 
 			// map all values from the JSON object into the new book element
-			new FromFlatJsonVisitor().visit(book, arg.jsonElement.getAsJsonObject());
+			book.accept(new FromFlatJsonVisitor(arg.jsonElement.getAsJsonObject()).ignoreBag(BAG_RELATIONS));
 
-			// add command to update the resource
-			UpdateResourceCommand cmd = new UpdateResourceCommand(getContainer(), tx);
-			cmd.setResource(book);
-			tx.addCommand(cmd);
+			// save changes
+			tx.update(book);
 
 			// notify the TX that it should commit on close
 			tx.commitOnClose();
 		}
 
 		// map the return value to JSON
-		JsonObject result = book.accept(new StrolchElementToJsonVisitor().flat());
+		JsonObject result = book.accept(new StrolchRootElementToJsonVisitor().flat());
 
 		// and return the result
 		return new JsonServiceResult(result);