topic Re: [resolved] Empty/Null fields show up in json output twritejsonfield in Talend Studio

[resolved] Empty/Null fields show up in json output twritejsonfield

jkrfs — Tue, 15 Jan 2013 20:30:04 GMT

I have a flow going into tWriteJsonFIELD which creates an array
{docs:}
However, if lets say the date is missing in one of the fields, it looks like this:
{docs:}
]}
Which is not what I want. If the field is empty/null I do not want it to show up in the output at all, like so:
{docs:}
Does anyone have any advice or ideas on how I can achieve this?
Thank you!

Re: [resolved] Empty/Null fields show up in json output twritejsonfield

Anonymous — Wed, 16 Jan 2013 05:48:48 GMT

Hi
It is impossible to generate the result as you expected by modifying anything on tWriteJasonField, try to replace null with another date or handle the string further after tWriteJasonField, for example, replace all the string ",\"date\":[]"with empty string.
Shong

Re: [resolved] Empty/Null fields show up in json output twritejsonfield

jkrfs — Wed, 16 Jan 2013 14:51:43 GMT

Good thinking Shong, I like the idea of just searching for the whole field and removing it altogether.
Thanks!

Re: [resolved] Empty/Null fields show up in json output twritejsonfield

jkrfs — Wed, 16 Jan 2013 21:42:44 GMT

I added a tJavaRow after tWriteJSONField and did this:
output_row.output = input_row.output.replaceAll(",\"*\":\\", "");
Works like a charm.

Re: [resolved] Empty/Null fields show up in json output twritejsonfield

Anonymous — Thu, 17 Jan 2013 06:17:36 GMT

I added a tJavaRow after tWriteJSONField and did this:
output_row.output = input_row.output.replaceAll(",\"*\":\\", "");
Works like a charm.

Cool, thanks for your feedback and the solution.
Shong

Re: [resolved] Empty/Null fields show up in json output twritejsonfield

Anonymous — Tue, 29 Jul 2014 13:51:39 GMT

BTW, for those, who faced similiar problem:
regex provided by jkrfs works for his case, but will not work if you have fields with underscore character or digits in name. Use this instead:
replaceAll(",?\"*\":\\", "");

Re: [resolved] Empty/Null fields show up in json output twritejsonfield

Anonymous — Wed, 30 Jul 2014 02:14:52 GMT

BTW, for those, who faced similiar problem:
regex provided by jkrfs works for his case, but will not work if you have fields with underscore character or digits in name. Use this instead:
replaceAll(",?\"*\":\\", "");

Hi Andrey
Thanks for offering a more comprehensive expression.
Best regards
Shong

Re: [resolved] Empty/Null fields show up in json output twritejsonfield

_AnonymousUser — Thu, 03 Nov 2016 23:49:27 GMT

I have a flow going into tWriteJsonFIELD which creates an array
{docs:}
However, if lets say the date is missing in one of the fields, it looks like this:
{docs:}
]}
Which is not what I want. If the field is empty/null I do not want it to show up in the output at all, like so:
{docs:}
Does anyone have any advice or ideas on how I can achieve this?
Thank you!

Hi,
How did you achieve the below using the twriteJson, Please assist.
{docs:}

Thanks,

Re: [resolved] Empty/Null fields show up in json output twritejsonfield

Anonymous — Sun, 06 Nov 2016 09:01:33 GMT

Hi,
How did you achieve the below using the twriteJson, Please assist.
{docs:}

Thanks,

Hello Naina
It seems your problem is not related to this subject. In order to better manage and follow up your questions, please report a topic for your question.
Regards
Shong

Re: [resolved] Empty/Null fields show up in json output twritejsonfield

Anonymous — Mon, 30 Jan 2017 22:04:27 GMT

I'm wondering how the behavior reported here isn't a bug. When the values are empty, how does it make sense to convert it to []? This is especially bad because, at the opposite end, tExtractJSONFields doesn't recognize those [], and either turns it into a literal string of "[]" or (for numbers) throws an exception. I added this hack, and it's working. Is there no option to avoid the hack?