Closes#27.
Guild membership is now the whole gate. `discordCallback` checks membership
(and `DISCORD_REQUIRED_ROLE` when set), then `Store.EnsureReader` creates the
Reader on first sight and returns the same row on every later login. The
refusal returns before `EnsureReader`, so a turned-away sign-in leaves no row
behind. `OWNER_DISCORD_ID` still seeds the owner, but only as the
administrator — it no longer gates login.
The cutover grace path goes with it: `API_TOKEN`, `API_TOKEN_GRACE_UNTIL` and
the legacy branch in `httpmw.ResolveReader` are deleted, so a credential
authenticates exactly one Reader or nothing. `userscript.Handler` drops its
re-derivation too — the resolved path segment is already the credential.
New surfaces: an empty library offers both install links (behind the
tab-specific empty states, so "No favourites yet" still wins), and the owner
alone gets a Readers panel with `POST /readers/{id}/revoke`. The owner's own
row is not revocable — 404, not a self-logout.
Isolation is asserted from both directions for read, modify and delete, and
the shared-series invariant is pinned: two Readers on one series produce one
series row, two independent progresses, one poll per due cycle, and one
Reader's delete leaves the other's bookmark and the poll intact.
Verified: `go test ./...` green; live smoke against a throwaway Postgres —
empty-library state in both colour branches, roster rendering, a real revoke
through the panel (target 401s next request, owner untouched), owner
self-revoke refused 404, per-Reader `/u/<cred>` and bearer auth both 200 with
404 for an unknown credential.
Reviewed-on: #36
Co-authored-by: Sulthan Zaki <sultankiki05@gmail.com>
Co-committed-by: Sulthan Zaki <sultankiki05@gmail.com>
Implements #23 per ADR-0002.
- Discord authorization code grant (identify + guilds.members.read), form-encoded token exchange
- Guild membership gate via the single-guild endpoint; optional DISCORD_REQUIRED_ROLE (empty default)
- Owner Discord ID is the only identity allowed to sign in
- Sessions are DB rows with opaque random ids; cookie carries only the id; expiry enforced; delete = revoke
- HMAC session signing, derived key, and WEB_PASSWORD removed; no replacement signing secret
- Login rate limiting preserved on the callback
- Full flow tested through the real router against a local Discord stub (DISCORD_API_BASE)
- Env: DISCORD_CLIENT_ID/_CLIENT_SECRET/_GUILD_ID/_REQUIRED_ROLE/_API_BASE/_REDIRECT_URI; docs updated
go test ./... passes.
Reviewed-on: #31
Co-authored-by: Sulthan Zaki <sultankiki05@gmail.com>
Co-committed-by: Sulthan Zaki <sultankiki05@gmail.com>