Prebid doesn't recognize CMP

Question

I'm trying to setup Prebid to send a GDPR consent value to SSPs. I've implemented CMP but in console I can see that Prebid just ignores it

WARNING: CMP not found. Resuming auction without consent data as per consentManagement config. undefined

I've no idea why Prebid doesn't recognize CMP, it is IAB compliant so everything should be ok. Any ideas where I made mistake?

Edit: The problem is I implemented setup from prebid.org to my site

        pbjs.que.push(function() {
          pbjs.setConfig({
      consentManagement: {
        cmpApi: 'iab',
        timeout: 5000,
        allowAuctionWithoutConsent: true
      }
    }); 

Also made a change to prebid.js file which now contains consentManagement adapter.

script type="text/javascript" src="http://testowa.epizy.com/prebid2.9.0.js" async>

I built a digi-trust cmp from https://github.com/adform/cmp and also implemented it on my site.

Everything looks ok, CMP works fine, I get an consent and I can see it in my console. However Prebid dosen't see that there is an CMP and it throws out a warning with an information I've mentioned before.

So even though I get consent and see cookie the request for an ad goes without it because prebid doesn't recognize it.

I need that consent to go with an ad request to SSPs.

Hope I made it a bit easier to understand what my problem is. I could provide a test page if needed.

Answer 1

For whatever reason it doesn't recognise the cookie, a possible fix is just to send the cookie as static:

{
  cmpApi: 'static',
  timeout: 5000,
  allowAuctionWithoutConsent: true,
  consentData: {
    getConsentData: {
      gdprApplies: true,
      hasGlobalScope: false,
      consentData: 'COOKIE CONTENT'
    },
    getVendorConsents: {
      metadata: 'COOKIE CONTENT',
      gdprApplies: true
    }
  }
}

This way you would send the whole cookie so it should work, but note that you need all attributes I mention above (prebid issues not related to this). Make sure you validate the cookie though, just to be sure.

Answer 2

It sounds like you haven't implemented the __cmp stub function. This is what should happen on your page:

• Define the window.__cmp() function (inline or synchronously)
• Load the CMP (cmp.bundle.js) asynchronously which replaces window.__cmp() with the actual CMP.
• Load Prebid asynchronously

Prebid.js calls __cmp().ping() to see if the real __cmp() has been loaded. If __cmp() doesn't exist at all it just assumes that you haven't implemented a CMP and goes ahead with the auction.

Check out the 'Setup Script' chapter of the DigiTrust CMP documentation. The required code is also here: https://github.com/InteractiveAdvertisingBureau/GDPR-Transparency-and-Consent-Framework/blob/master/CMP%20JS%20API%20v1.1%20Final.md#CMP-stub-sample

Answer 3

I had the same problem. I got it working when I loaded the CMP script synchronously before prebid.js library, with the consent management module included.

also changed: allowAuctionWithoutConsent: false