piano analytics support

[nathangoulding]

Fixes issue #1769.

[dvoytenko]

/to @avimehta

[avimehta]

@nathangoulding While looking at examples today, I realized that your config does not contain a client id scope. Can you Send out a PR to add the scope/cookie name? Without that, the client id value will be empty.

'amp_client_id=${clientId}&aid=${aid}',

[nathangoulding]

Ahh yeah, will do.

[avimehta]

Thanks, Please cc me on the pull request.

[nathangoulding]

@avimehta Looking over the documentation for this now. It sounds like the clientId is tied to a logged-in user - is that correct? I thought the clientId was generated by the AMP viewer and was always populated, effectively a unique viewerId (equivalent of a browserId for mobile browsers). I'm not sure I understand the significance of the clientId.

Is there a way to get an automatically generated viewerId? There's also mention of reading a fallback cookie, but it's unclear how a 3rd-party analytics provider could set a first-party cookie that could get read by AMP.

Could you point me to the documentation on this?

[rudygalfi]

@nathangoulding clientId is not tied to authenticated data. Here's the design doc from the ITI (#961): https://docs.google.com/document/d/1f7z3X2GM_ASb3ZCI_7tngglxwS6WoWi1EB3aKzdf6vo/edit

[avimehta]

@nathangoulding Someone recently asked about the client id setup for piano analytics configuration. The way it is setup currently, the value of amp_client_id is always ''. Using client id without a parameter also results in an error getting logged in console. Can you find out what the right thing for you here would be?

• You can pass in a cookie name like: ${clientId(cookieName)} and the viewer will generate an id for you that is persisted per browser.
• You can remove the ${clientId} from your configuration completely.