League Visibility

Every league is public or private.

The rule

• A public league can be joined by any authenticated player, with nothing in hand. It has no invitation code, there is nothing for one to guard.
• A private league can be joined only by presenting its invitation code. There is no exception for its league admin, and none is needed: an admin is already in the league they own, see below, so there is nothing for an exception to let in.

The Global League is public, and therefore codeless. It is the one league every player is enrolled in on first login, so it must stay joinable by anyone.

Visibility governs joining, not reading

This is the part the original GDD does not say, and the part most likely to be assumed the other way round.

A private league's page, factsheet and standings stay readable by anyone who has its id. Only joining is gated. Someone handed an invitation should be able to see what they are being invited to, how many teams, which Wikipedia edition, how much season is left, before committing to it, and the standings have always been served unscoped anyway.

The league id is therefore not a secret and never was a credential. The invitation code is the credential.

Who may hand the code out

Each league carries an invite policy, chosen on the creation form. It only means anything for a private league, since a public one has no code:

• members: any player fielding a team in the league can share the code.
• admin: only the league admin can.

A public league still stores a policy, and creation still insists on one. It decides nothing today, but a league that later turned private with no policy recorded would be read as admin, a rule nobody chose, arrived at by omission.

The founder is a member

Creating a league and fielding a team in it are one act: the league row and its founder's team are written in the same transaction, so there is no moment at which a league exists that nobody is in. This matters beyond tidiness, the league list is scoped to the leagues a player has a team in, so a league written without its founder would be invisible to everyone, and a private one would hold an invitation code nobody could reach.

The founder is the league's admin, and because founding is joining, an admin is a member by construction and never has to get past the gate at all. Nor is there a back way in for one who left: leaving hands the league on in the same transaction, so a founder coming back to their own private league presents its code like anybody else. The gate therefore never has to name the admin.

A caller the policy does not allow is answered exactly as if the league did not exist. Telling a stranger that a code exists tells them there is something worth guessing at.

Related

• League Season: the other thing fixed at creation: when the season starts and how long it may run.
• League Lifecycle: the other gate on joining (a league that has ended or been closed admits nobody), and the admin's other privilege: closing the league they own.
• ADR 0008: League Invitation Codes: the code's format, where it may travel, and how the join is enforced.
• FantaWiki Requirements: the original public/private definition (glossary) and the create/join user stories.
• API Naming Rules: §5, on choosing between 403 and 404 for a refusal.