| Key | Field | Type | Description | Requiredness | Default value |
| 1 | url | url.Url | Web: The "raw" value in here is the value of
document.referrer as reported by the browser
Native app: If this is populated, we will use it.
If it is not populated, it will be synthesised using
the nativeAppSource field.
| optional | |
| 4 | component | string | the component that was clicked on for this referral,
if the previous page was served by the guardian
| optional | |
| 10 | linkName | link.LinkName | The link name associated with the element clicked.
| optional | |
| 5 | platform | platform.Platform | the platform of the referrer,
if the previous page was served by the guardian
| optional | |
| 6 | viewId | string | the viewId of the referrer,
if the previous page was served by the guardian
| optional | |
| 7 | email | string | if this was from a guardian email, what email it was
| optional | |
| 8 | nativeAppSource | source.Source | If this referral was from a native app, the source of the referral
| optional | |
| 9 | google | googlereferral.GoogleReferral | If this referral was from google, and we have additional data on the query string,
the values we got.
| optional | |
| 11 | tagIdFollowed | string | | optional | |
Information about the referrer - previous page - that the reader navigated to
this one from.