Re: Using DATA-GEN to generate JSON

Not sure what the heck YAGL is Darryl - did you mean YAJL?

Most people use Scott's generator. Where did you get this one?

Regardless, you need to use countprefix to correctly output arrays. By "correctly", I mean only outputting the number of elements that have been filled. BUT outputting empty elements should not cause a crash, regardless.

As always, it would be helpful if you had actually included a sample of the DS and Data-Gen you are using.

This is roughly what it should look like.

Dcl-ds Invoice Qualified Inz;
CustomerId char(6);
Invoice_Number int(10);
count_Invoice_Detail int(5);
Dcl-ds Invoice_Detail Dim(20);
Item char(10);
Quantity int(5);
...
End-ds;
End-ds;

Then the DG would include this:

%Data( json : 'doc=file countprefix=count_ ')


Be aware, though that this may not answer all of your problems. If I recall correctly, one of the issues with DG is that it will output an empty array when the count is zero.

e.g. if count_Invoice_Detail = zero the output would include:

... { "Invoice_Detail" : [ ] } or something like that.

You can see an example that uses countprefix for an optional field in this article https://www.itjungle.com/2021/07/12/guru-web-services-data-into-and-data-gen-part-3/.

For documents that include optional blocks, you will need to use DG's *Start and *End options and output the json in pieces.

Alternatively, for highly complex documents with a lot of optional "bits", you may need to use the raw APIs in YAJL.



Jon Paris
Jon.Paris@xxxxxxxxxxxxxx

On Sep 11, 2025, at 8:30 PM, <dfreinkel@xxxxxxxxxxxxxxxxx> <dfreinkel@xxxxxxxxxxxxxxxxx> wrote:

No, I did not see parameters for those.

Darryl Freinkel

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