Issues Reading cookies on First Page Load?

[Anonymous]

I have a script that parses my URL and writes parameters to cookies. I can see this functioning with proper cookies being set.

However, when I submit my form the cookies don't appear to be read. All applicable fields are blank or at defaults.

If I go back and resubmit the form, the cookies are read and submit through.

Ideas?

Thanks,

Ben Brooks

[Josh_Hill13]

Need code or url.

Sanford Whiteman​

[Anonymous]

Good call:

https://info.nintex.com/cnt_corp_buyers_guide_0717_lp_o365_bdm.html

https://info.nintex.com/cnt_corp_demystifying_workflow_ebook_0717_lp_o365_bdm.html

[SanfordWhiteman]

Thanks Josh -- yes, Ben, you need to provide a URL.

Setting cookies is a synchronous operation, but if for some reason you kick off your code after the Marketo form is rendered, the form can't pick up the cookie values.

[Anonymous]

Interesting. My cookie setting code in GTM fires on dom.ready and it usually takes longer for the form to load, but that could be an issue.

[SanfordWhiteman · Accepted solution]

That needs to be fixed, as the form can render before or after the DOM is ready (DOMContentLoaded).  Very important to listen for Forms API events, not built-in DOM events.  If simply using GTM tags independent of each other, you'll always have a race condition (since the script-injected scripts are all asynchronous). You have to interlink these somehow, either by running MktoForms2.loadForm after setting cookies or by re-reading the values at form.whenReady() and running addHiddenFields.

[Anonymous]

Thanks Sanford. Apologies for the delay. Is there a good resource you can point me to that explains either how to delay loading the form or adding the hidden fields?

[SanfordWhiteman]

The Forms 2.0 API method addHiddenFields is documented here: http://developers.marketo.com/javascript-api/forms/api-reference/

You can also search my posts here as I use this method a lot.

[SanfordWhiteman]

Ben, observe what happens when I force a 3-second delay on gtm.js on your page (using the proxy server in my test lab). I'm loading with ?utm_campaign=c1 in the URL.

The document.cookie is populated correctly on its own:

But the cookie work happened after the form loaded, so the form does not contain utmcampaign:

Now if I switch it around, letting gtm.js load at regular network speed and forcing a 3-second delay on the form loading, I get the cookie:

AND I now get the form field:

If it's surprising that a form on a Marketo-hosted LP can finish rendering before GTM finishes injecting its script tags, consider that (unlike an embedded form) a form on a Marketo LP doesn't need to load the descriptor from Marketo (it's printed right into the LP). So while there is still a little bit of indirection, it's perfectly feasible for the Forms2 library to create a form from the descriptor and get the form completely ready before your GTM stuff runs. Even if it's a difference of 50ms that'll upset your plans.

[SanfordWhiteman]

Off-topic (somewhat) while I was looking at your network traffic I noticed you fall victim to a form of this: http://blog.teknkl.com/flop-timized-marketo-lps-and-the-case-of-the-350kb-favicon/