topic Re: DataMapper - Transform JSON array to XML in Talend Studio

DataMapper - Transform JSON array to XML

param75 — Tue, 25 Oct 2016 08:50:51 GMT

Hi,
I use a mapping (component tHMap) to transform data from a JSON to XML.
However, I do not know how to retrieve the first, second (or more) values of a JSON array.
My first step would be to just get the first item and place it in the first tag category_1.
Ditto for the next elements.
"category" field into my JSON file:

"category":

Here is the structure that I want to generate:

<categories>
	<category_1>test</category_1>
	<category_1>test_talend_2</category_1>
	<category_1>test_talend</category_1>
</categories>

Here is my mapping (Map):

I think we should to use a Loop function but i dont know how to use it:

Properties of "category" in JSON structure:

My second step is to sort the values by string length. Exemple:

<categories>
	<category_1>test</category_1>
	<category_1>test_talend</category_1>
	<category_1>test_talend_2</category_1>
</categories>

Is there a function for this in DataMapper?
Thks all.

Re: DataMapper - Transform JSON array to XML

Anonymous — Fri, 04 Nov 2016 02:20:54 GMT

Hello,
We have re-directed your issue to TDM expert and then come back to you as soon as we can.
Best regards
Sabrina

Re: DataMapper - Transform JSON array to XML

Haitao — Fri, 04 Nov 2016 10:17:59 GMT

Hello PM_param, what's your expected output?

a loop of category_1?

<categories>
 <category_1>test</category_1>
 <category_1>test_talend_2</category_1>
 <category_1>test_talend</category_1>
</categories>

category_1 and category_2 and category_3?

<categories>
 <category_1>test</category_1>
 <category_2>test_talend_2</category_2>
 <category_3>test_talend</category_3>
</categories>

a sorted loop of category_1?

<categories>
 <category_1>test</category_1>
 <category_1>test_talend</category_1>
 <category_1>test_talend_2</category_1>
</categories>

Something else?

Re: DataMapper - Transform JSON array to XML

Haitao — Fri, 04 Nov 2016 14:53:15 GMT

To get the 2nd type of output, please use the AgConcat and SingleIndex functions as below

Re: DataMapper - Transform JSON array to XML

param75 — Fri, 04 Nov 2016 15:35:57 GMT

Hi hnie,
Thank's for your answer, the expected ouput is the lowest value in category 1, category 2 in the second and last (the longuest value) in category 3.
Today i resolve the first problem which was the XML structure. Now the field is set as below:

In my Map, I loop on "category" and I recovers only one that interested me as below:

However I think there is a simpler method to get the right values, no? There is a function for compare values length?
Thank's for you help.

Re: DataMapper - Transform JSON array to XML

Haitao — Wed, 09 Nov 2016 22:54:25 GMT

Functions/String/StringLength and Functions/Comparison and Logical/* will allow your to compare values length.

Re: DataMapper - Transform JSON array to XML

param75 — Mon, 14 Nov 2016 12:21:09 GMT

Thank's for reply, I used a RegEx for determine category to use.
category_1:

category_2:
category_3:
However, when I click on "Test Run", I have the bug:
" Exception during test run:

Thread Expr in$/Root/hits/hits/_source/category enclosing node: out$/Root/RequiredRecord/souscategorie_value != out$/Root/RequiredRecord/souscategorie2_value"
I specify that I use this function in several Maps. On the other Map (1 only), everything is ok.
There is a problem with json structure?