How can I map a JS value based on certain DOM conditions?

[rjbueno]

I want to check for an DOM element's existence, then create/set a variable based on that condition, then map this variable value to a tag. Should this be done in a JS extension? If so how would I create the data layer variable to map (or do I have to do that)?

[Srinivasan]

@rjbueno

Please have deep dive into the below related links which you are looking for,

https://community.tealiumiq.com/t5/Tealium-iQ/JavaScript-Code-Extension/ta-p/11925

https://community.tealiumiq.com/t5/Tealium-iQ/Javascript-Extension-Output-DOM-Scraping-How-to-send-t...

https://community.tealiumiq.com/t5/Tealium-iQ/DOM-Ready-JavaScript-Extensions-amp-Isolation/m-p/5203...

Hope it help!

[steve_lake]

Further to the answer from @Srinivasan - you can actually do this using just a set data values extension, with a condition.  Then just take the output from the extension (in this case, test_trait) and map it to the required tag. 

If you need to create a new data source you can add it directly from the extension, by pressing the + button in the middle of the configuration box (see below)

You could also scope the extension to the tag, if you only want that data to be available for that exact tag. 

[rjbueno]

I don't think the "set data values" extension will allow custom JS.  I will need that to parse the DOM and set my value.  

[rjbueno]

One other thing I forgot to mention, I noticed that there is no conditional configuration option available on the custom JS extension.  Is there a way to isolate the custom JS to a specific URL (aside from the custom JS to detect the path, etc.)?

[rjbueno]

Can I use a ternary conditional in the JS value field of the "Set Data Value" extension?

something like

[if DOM element exists] ? 'value one' : 'value two';

[steve_lake]

You can use a ternary conditional in the JS value field, yes.