AEM code snippets : export page data as json format using sling model exporter

In my previous article’s you have seen how to export page data as a JSON format using servlet, now, I am going to explain exporting page content as JSON using sling models exporter, using sling model exporter you can get below advantages

No need to write servlet to export data as JSON format
You can use same code which is written using sling models to render content and to export as JSON format

The below things are developed on AEM 6.3 so, we do not need to install any other dependencies

Sling model exporter is very useful when you want to publish your data to third party system’s or consuming within the site using ajax request if you have sling models and wants to serialize them, by providing @Exporter annotations to the existing sling models you can convert your model as CaaS based URL

Here, I am serializing list collections component data, the text property I am returning as it is and also returning child nodes of the configured path which is a nodePath property

Step 1: create a model

Here, I have created a simple list collection model which contains three properties getText(), getLinks() and getMessage()

The getText() returns whatever data is authored in the authoring dialog
The getLinks() read path from the authoring dialog and return all child nodes
The getMessage() returns static text

If you see the below code, the sling model exporter is not only serializing injected properties it is also serializing custom properties which are getMessage()

package com.aem.toolkit.core.models;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import javax.annotation.PostConstruct;
import javax.inject.Inject;
import javax.inject.Named;
import org.apache.sling.api.resource.Resource;
import org.apache.sling.api.resource.ResourceResolver;
import org.apache.sling.models.annotations.Default;
import org.apache.sling.models.annotations.DefaultInjectionStrategy;
import org.apache.sling.models.annotations.Exporter;
import org.apache.sling.models.annotations.ExporterOption;
import org.apache.sling.models.annotations.Model;
import com.day.cq.wcm.api.Page;

@Model(adaptables = Resource.class, resourceType = "examples/components/content/listcollection", defaultInjectionStrategy = DefaultInjectionStrategy.OPTIONAL)
@Exporter(name = "jackson", extensions = "json", options = {
		@ExporterOption(name = "MapperFeature.SORT_PROPERTIES_ALPHABETICALLY", value = "true"),
		@ExporterOption(name = "SerializationFeature.WRITE_DATES_AS_TIMESTAMPS", value = "false") })
public class ListCollectionModel {

	public static java.util.List<PageBean> links = new ArrayList<PageBean>();
	Resource resource;

	@Inject
	@Named("sling:resourceType")
	@Default(values = "No resourceType")
	protected String resourceType;

	@Inject
	@org.apache.sling.models.annotations.Optional
	private String text;

	@Inject
	@org.apache.sling.models.annotations.Optional
	private String nodePath;

	private String message;

	@Inject
	private Resource res;

	@Inject
	private ResourceResolver resourceResolver;

	@PostConstruct
	protected void init() {
		message = "Welcome to keys and strokes technical blog";
	}
	public List<PageBean> getLinks() {
		resource = resourceResolver.resolve(nodePath);
		links.clear();
		if (resource != null) {
			Iterator<Resource> linkResources = resource.listChildren();
			linkResources.forEachRemaining(res -> populateModel(res));
		}
		return links;
	}
	public void populateModel(Resource resource) {
		PageBean link = new PageBean();
		Page page = resource.adaptTo(Page.class);
		if (page != null) {
			if (page.getTitle() != null) {
				link.setTitle(page.getTitle());
				link.setPath(page.getPath());
			}
			links.add(link);
		}
	}
	public String getMessage() {
		return message;
	}
	public String getText() {
		return text;
	}
}

package com.aem.toolkit.core.models;

import java.util.ArrayList;

import java.util.Iterator;

import java.util.List;

import javax.annotation.PostConstruct;

import javax.inject.Inject;

import javax.inject.Named;

import org.apache.sling.api.resource.Resource;

import org.apache.sling.api.resource.ResourceResolver;

import org.apache.sling.models.annotations.Default;

import org.apache.sling.models.annotations.DefaultInjectionStrategy;

import org.apache.sling.models.annotations.Exporter;

import org.apache.sling.models.annotations.ExporterOption;

import org.apache.sling.models.annotations.Model;

import com.day.cq.wcm.api.Page;

@Model(adaptables = Resource.class, resourceType = "examples/components/content/listcollection", defaultInjectionStrategy = DefaultInjectionStrategy.OPTIONAL)

@Exporter(name = "jackson", extensions = "json", options = {

@ExporterOption(name = "MapperFeature.SORT_PROPERTIES_ALPHABETICALLY", value = "true"),

@ExporterOption(name = "SerializationFeature.WRITE_DATES_AS_TIMESTAMPS", value = "false") })

public class ListCollectionModel {

public static java.util.List<PageBean> links = new ArrayList<PageBean>();

Resource resource;

@Inject

@Named("sling:resourceType")

@Default(values = "No resourceType")

protected String resourceType;

@Inject

@org.apache.sling.models.annotations.Optional

private String text;

@Inject

@org.apache.sling.models.annotations.Optional

private String nodePath;

private String message;

@Inject

private Resource res;

@Inject

private ResourceResolver resourceResolver;

@PostConstruct

protected void init() {

message = "Welcome to keys and strokes technical blog";

}

public List<PageBean> getLinks() {

resource = resourceResolver.resolve(nodePath);

links.clear();

if (resource != null) {

Iterator<Resource> linkResources = resource.listChildren();

linkResources.forEachRemaining(res -> populateModel(res));

}

return links;

}

public void populateModel(Resource resource) {

PageBean link = new PageBean();

Page page = resource.adaptTo(Page.class);

if (page != null) {

if (page.getTitle() != null) {

link.setTitle(page.getTitle());

link.setPath(page.getPath());

}

links.add(link);

}

public String getMessage() {

return message;

}

public String getText() {

return text;

}

The resourceType is an optional one, here I am assigning it to my custom listcollection component, which is resourceType = “examples/components/content/listcollection”

The sling models exporter uses Jackson framework which helps us serialize models as JSON format so, you need to provide exporter name as “jackson” and extensions should be “json”

The selector is optional one, if you don’t provide anything then it will take default selector which is “model”

Once, the build and deployment is done then test it using HTL and Rest based Url

Step 2: Test it using HTL

Check below screenshot using HTL, I am rendering the list collection model data

The output is something like below

Step 3: Test it with the REST-based URL

If you hit the URL then you should see something like below, here the “model” is selector

http://localhost:4506/content/examples/en/jcr:content/root/responsivegrid/listcollection.model.json

1	http://localhost:4506/content/examples/en/jcr:content/root/responsivegrid/listcollection.model.json

Step 4: Ignore properties

In some use cases where you don’t want to export all the properties as JSON format, there, you can use Jackson ignore annotation, check the below code and I would recommend you to refer this link to get more information on jackson annotations Jackson Annotations, if you use this then the property will not be serialized

	@JsonIgnore
	private String message;

1 2	@JsonIgnore private String message;

But, for this, you need to load Jackson dependencies

<dependency>
  <groupId>com.fasterxml.jackson.core</groupId>
  <artifactId>jackson-core</artifactId>
  <version>2.5.3</version>
</dependency>

<dependency>
  <groupId>com.fasterxml.jackson.core</groupId>
  <artifactId>jackson-annotations</artifactId>
  <version>2.5.3</version>
</dependency>

<dependency>
  <groupId>com.fasterxml.jackson.core</groupId>
  <artifactId>jackson-databind</artifactId>
  <version>2.5.3</version>
</dependency>

<groupId>com.fasterxml.jackson.core</groupId>

<artifactId>jackson-core</artifactId>

</dependency>

<groupId>com.fasterxml.jackson.core</groupId>

<artifactId>jackson-annotations</artifactId>

</dependency>

<groupId>com.fasterxml.jackson.core</groupId>

<artifactId>jackson-databind</artifactId>

</dependency>

Step 5: prior versions of AEM

If you are working on prior version’s of AEM 6.3 then you must load below sling model 1.3.0 dependencies and remaining things are same

<dependency>
   <groupId>org.apache.sling</groupId>
   <artifactId>org.apache.sling.models.api</artifactId>
   <version>1.3.0</version>
   <scope>provided</scope>
</dependency>
<dependency>
   <groupId>org.apache.geronimo.specs</groupId>
   <artifactId>geronimo-atinject_1.0_spec</artifactId>
   <version>1.0</version>
   <scope>provided</scope>
</dependency>

<groupId>org.apache.sling</groupId>

<artifactId>org.apache.sling.models.api</artifactId>

<scope>provided</scope>

</dependency>

<groupId>org.apache.geronimo.specs</groupId>

<artifactId>geronimo-atinject_1.0_spec</artifactId>

<scope>provided</scope>

</dependency>

Download Code

sling model exporter

About Author

Raj

A technology enthusiast and a professional blogger from India. Through out my IT career, I have had the pleasure of working on various new technologies and built products like www.ziprides.com and some other products. Unfortunately, my attempts have not given me the desired results and as a result, I have finally decided to build a professional blog where I would like to share all my learnings and hoping to learn from other enthusiasts around the world.

Step 1: create a model

Step 2: Test it using HTL

Step 3: Test it with the REST-based URL

Step 4: Ignore properties

Step 5: prior versions of AEM

Related posts:

About Author

Raj