Fixes#1432
Refactors the invite + registration system to be simpler and more consistent
with regards to existing user invites. Previously, per-user invites are
stored in the user.invites dict instead of in the invites collection,
which creates a few issues:
- Existing user do not show up in Org Invites list: #1432
- Existing user invites also do not expire, unlike new user invites,
creating potential security issue.
Instead, existing user invites should be treated like new user invites.
This PR moves them into the same collection,
adding a `userid` field to InvitePending to match with an existing user.
If a user already exists, it will be matched by userid, instead of by
email. This allows for user to update their email while still being
invited. Note that the email of the invited existing user will not
change in the invite email. This is also by design: an admin of one org
should not be given any hint that an invited user already has an
account, such as by having their email automatically update. For an org
admin, the invite to a new or existing user should be indistinguishable.
The sha256 of invite token is stored instead of actual token for better
security.
The registration system has also been refactored with the following
changes:
- Auto-creation of new orgs for new users has been removed
- User.create_user() replaces the old User._create() and just creates the user with
additional complex logic around org auto-add
- Users are added to org in org add_user_to_org()
- Users are added to org through invites with add_user_with_invite()
Tests:
- Additional tests include verifying that existing and new pending
invites appear in the pending invites list
- Tests for `/users/invite/<token>?email=` and
`/users/me/invite/<token>` endpoints
- Deleting pending invites
- Additional tests added for user self-registration, including existing
user self-registration to default org of existing user (in nightly
tests)