Follow+Notes: Expose ability to retrieve current user's follower status for a grant via Finder API

[TylerHendrickson]

Subtask of [STORY]: Update 'Status' to 'Follow + Note' feature #2960

Blocked by

N/A

Blocks

• Follow+Notes: Implement Grant Activity card component in Grant Details view #3406

Definition of Done

A new API route exists that allows users retrieve followers (within the same tenant/organization) of a particular grant.

Implementation Details

• In packages/server/src/lib/grantsCollaboration/followers.js, update the exported interface with the following functions:
  • getFollowerForGrant(knex, grantId, userId)
    • Performs a query that retrieves a single row in the grant_followers table for the identified grant and user combination.
    • The knex argument represents a knex connection object, e.g. as implemented by the existing followGrant() function.
    • Returns null if the identified user does not follow the identified grant, else the following data structure:

      {
        id: grant_followers.id,
        grant: { id: grant_followers.grant_id },
        user: {  id: grant_followers.user_id },
        createdAt: grant_followers.created_at,
      }

• In packages/server/src/lib/grantsCollaboration, import/export the getFollowerForGrant() function exported from packages/server/src/lib/grantsCollaboration/followers.js
• In packages/server/src/routes/grants.js, define a new GET /:grantId/follow API route handler as follows:
  • Requires authentication.
  • Calls getFollowerForGrant() from packages/server/src/lib/grantsCollaboration with the grant ID from request path parameters and the authenticated user's ID.
  • If the call to getFollowerForGrant() returns an object (instead of null), provides the function's return value as a JSON-serialized response with status code 200
  • If the call to getFollowerForGrant() returns null, provides a standard 404 response