I need to create a custom token for a custom content type in Drupal 8.
there is a field, e.g 'field_image' I'm trying to use Token Custom module to pull the value of the filed and into the token.
The token itself is used in the 'Metatag' module to provide a value for an OG:image
this means that the Content-type needs to assign the image name into the token so that when the content is viewed, the image URL appears in the property.
I have no idea where to start on pulling this value from the field, I've looked at field_tokens module but I'm not sure where to start with this one.
The Custom Content type is from a third party module that I have no control of its development but I can develop for D8 no problem.
Does anyone have any ideas?