support form submissions

[techieshark]

This would be useful:
https://legacydocs.hubspot.com/docs/methods/forms/get-submissions-for-a-form

Example GET URL:
https://api.hubapi.com/form-integrations/v1/submissions/forms/583d14ff-91af-403d-b94a-c8b5d954da6f

Example response:

{
 "results": [
   {
     "submittedAt": 1547130102576,
     "values": [
       {
         "name": "email",
         "value": "[email protected]"
       },
       {
         "name": "company",
         "value": "Example Co"
       },
       {
         "name": "phone",
         "value": "123 555 4567"
       }
     ],
     "pageUrl": "https://www.example.com/form"
   },

See also:

• Airbyte implementation https://github.com/airbytehq/airbyte/blob/fbc63ee0616250109bc643127090f689d41e17f6/airbyte-integrations/connectors/source-hubspot/source_hubspot/streams.py#L1769
• gitlab/hotglue implementation: https://gitlab.com/hotglue/tap-hubspot-beta/-/blob/master/tap_hubspot_beta/streams.py?ref_type=heads#L533

Note:

• The Hubspot API is AFAIK somewhat strange in that there are two places where (partial) info about a form submission can be found. First, the form submission API; that gives you things like the email address and other form values. Secondly, the Hubspot Contact API - each contact will have a nested object that has info about form submissions, and this is where one can identify the unique form submission ID (but it doesn't give you the values). So theoretically to get the full picture, as far as I can tell, one would actually need to piece together data from two different APIs. Which is... crazy and annoying, so maybe that should be considered in a separate task at some future point.