JSON Array with Web Service TRestClient

Francis28 — Fri, 02 Jan 2026 14:45:42 GMT

Hello,

I have a JSON file that looks like this:

I get JSON data from the web service using a TRESTClient component and I extract data with a tExtractJSONFields.

BUT I can't extract data from the "rapprochements" array.

I tried several JSON query unsuccesfully.

Any idea or suggestion ?

Thanks in advance for your help

Regards,

Re: JSON Array with Web Service TRestClient

anselmopeixoto — Sat, 08 Jul 2023 23:35:01 GMT

Hi @Francis Noyeau

Your JSON has two loops defined by its arrays: the root level array and the "rapprochements" array.

But the tExtractJSONFields component allows only one loop at the "Requéte de boucle JSONPath".

So, there are some approaches you can try and see what fits best for you:

A) Set the Loop Jsonpath query to iterate over the root array using the "$" operator (that is the root object/element of a JSON). And then, in the Mapping Json query, you could use expressions like:

"id"
"rapprochements[*].propositionId"
"rapprochements[*].demande.id"

One downside of this approach is that the component will not loop over the "rapprochements" element. Instead, it will output its subelements as an array.

B) Set the Loop Jsonpath query to iterate over the "rapprochements" array using the expression "$..rapprochements[*]". And then, in the Mapping Json query, you could use expressions like:

".propositionId"
".demande.id"

But notice that using this loop level, you wouldn't be able to reach the "id" on the parent level because the jsonpath doesn't have a parent operator (reference).

C) Change the "Read by" option on tExtractJSONField to use Xpath expressions and set the loop xpath query to "/rapprochements". And then, in the Mapping Xpath query, you could use expressions like:

"../id"
"./propositionId"
"./demande/id"

Notice that this approach use the same loop level as the previous, but it allows you to reach the elements at parent level using the ".." expression.

D) Finally, since you're using tRESTClient to get this JSON, you could use tXMLMap instead of tExtractJSONFields because tRESTClient automatically converts JSON responses to a DOM Document and looping over multiple levels using tXMLMap is far easier, in my opinion.

Re: JSON Array with Web Service TRestClient

Francis28 — Tue, 11 Jul 2023 10:26:06 GMT

Hi @Anselmo Peixoto

Thank you very much for your reply.

It helps me to solve my problem and to learn more about Jsonpath query

Regards

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JSON Array with Web Service TRestClient

Re: JSON Array with Web Service TRestClient

Re: JSON Array with Web Service TRestClient