Processing list in webscript response xml/json ftl

Hello everyone !

I am sure this would be helpful to you if you are looking for a solution about how to iterate over a list in the ftl. Let's start then.

Returning appropriate responses (xml/json ftls) are the must when you need to do further processing based on your webscript response.
Here, I am providing the code snippets which will be useful to you when you need to process/iterate over the list in your xml/josn ftls for your webscript response.

For example, consider a scenario, where in you have to get the name/noderefs of all the contents from one space. I am sure you would like to get this done by writing a webscript.
In your webscript backend class, you will perform a lucene query, and generally we prefer to use a List in java backed webscript. Hence, will populate the list with the result noderefs.
Now, you need to process this result list and return the name/noderef in the xml/json ftls as the webscript response.

To process a list in webscript response ftls, you need to do below things -

1. Java backed webscript -
 - In your java backed declarative webscript, initialize the model object.
   Map<String, Object> model = new HashMap<String, Object>();
 - Prepare the List object to be set.
   List<NodeRef>  resultList = new ArrayList<NodeRef>();
   resultList = queryResult(query) // You are invoking a function which has code for performing lucene query and return the list.
 - Populate the model object
   model.put("nodelist", resultList);
 - Do return the model object from your webcript backend class.
   return model;

2. If you want to return xml as the response. Then, use below code in your webscript's response xml.ftl (yourwebscript.xml.ftl)
   <?xml version="1.0" encoding="UTF-8"?>
    <#escape x as x?html>
    <nodes>
        <#list nodelist as node>
            <nodeid>${node.id}</nodeid>
            <name>${node.name}</name>      
        </#list>
    </nodes>
    </#escape>

3. If you want to return json as the response. Then, use below code in your webscript's response json.ftl (yourwebcript.json.ftl)
   <#escape x as jsonUtils.encodeJSONString(x)>
   {
   "nodes": [
         <#if nodelist??>      
             <#assign first=true>
             <#list nodelist as node>
                 <#if node??>
                    <#if !first>
                     ,
                    <#else>
                    <#assign first=false>
                     </#if>
                     {
                        "nodeid":"${node.id}",
                         "name":"${node.name}"
                     }                  
                 </#if>
             </#list>      
         <#else> </#if>
       ] 
   }
  </#escape>

Processing a list in ftl is simpler now. You may want to try it in your webscripts.

Thanks,
Ramesh C

Sending bytearray and other parameters to the webscript at the same time

Hey everyone !

There may be the scenarios where you want to upload a file to the alfresco repository through the webscript and also want to pass some parameters to the webscript.
That means you want to send the uploaded file (bytearray) alongwith some parameters to the webscript.

In this scenario, You definitely will think of writing a POST webscript. Absolutely fine.

However, It is not possible to send both the content (other parameters) and uploaded file to the webscript at the same time. You may try doing it from POSTER plugin, it will not allow.
Note : Poster is a firebug plugin I generally use for testing POST webscripts.

In order to send bytearray of the content and also pass other parameters to the webscript. Here is the trick.

You will need to do below -
1. Open poster
2. Provide your webscript URL.
    e.g. http://localhost:8080/alfresco/service/test/upload
3. Provide the parameters you want to send as the querystring. Hence, modify the URL as below.
    e.g. http://localhost:8080/alfresco/service/test/upload?nodeid=parentid&type=thumb
4. In poster, click on Content to send tab. Open the file you want to upload and Click on POST to hit the webscript.

In your controller class of the webscript -
You can retrieve the uploaded content as mentioned below.
1. For parameters, use request.getParameter("nodeid");  This we all have used.
2. To retrieve uploaded content, use request.getContent() and this way you will get the uploaded content. You can get the inputstream of the content and use it for further processing.

This way you can pass bytearray and other parameters to the webscript at the same time.

Hope this will help you at some point of your coding experience in alfresco.

Thanks,