fix(backend): propagate failure when granting data access

addDataAccessUser returns a Rejection rather than throwing, and the
empty else branch discarded it. The caller then stamped claimedAt, so
a failed insert burned the invite, granted nothing, and reported
success with no log or event.

Throw the Rejection (it extends GraphQLError) so the accept aborts
before the invite is marked claimed. Removes both TODOs.

Author: shivoomiess

apps/backend/src/mutations/InviteMutations.ts

@@ -482,27 +482,26 @@ export default class InviteMutations {
         continue;
       }
 
-      // TODO: what happens if there is an error during accept?
-      // we need graceful error handling from the database later
-      const isRejection =
-        await this.dataAccessUsersDataSource.addDataAccessUser(
-          claim.proposalPk,
-          claimerUserId
-        );
+      const failure = await this.dataAccessUsersDataSource.addDataAccessUser(
+        claim.proposalPk,
+        claimerUserId
+      );
 
-      if (!isRejection) {
-        this.eventBus.publish({
-          type: Event.PROPOSAL_DATA_ACCESS_INVITE_ACCEPTED,
-          isRejection: false,
-          key: 'proposal',
-          loggedInUserId: claimerUserId,
-          invite: invite,
-          description: `User with ID ${claimerUserId} accepted data access invite for proposal ${claim.proposalPk}`,
-          proposalPKey: claim.proposalPk,
-        });
-      } else {
-        // TODO: what happens if there is an error during accept?
+      // Rejection extends GraphQLError, so throwing aborts the accept before
+      // the invite is stamped as claimed.
+      if (failure) {
+        throw failure;
       }
+
+      this.eventBus.publish({
+        type: Event.PROPOSAL_DATA_ACCESS_INVITE_ACCEPTED,
+        isRejection: false,
+        key: 'proposal',
+        loggedInUserId: claimerUserId,
+        invite: invite,
+        description: `User with ID ${claimerUserId} accepted data access invite for proposal ${claim.proposalPk}`,
+        proposalPKey: claim.proposalPk,
+      });
     }
   }