The counters this fills are the ones the windows already knew how to read.
What was missing was anything that put a number in them.
Burn is recorded as segments: one stretch of one run at one unchanging rate,
opened when the rate becomes true and closed when it stops being. Not a row per
session, because a session's rate does not survive its own lifetime — a second
run changes what the account spends per second while the first is still going,
and a rate that applied from that moment must not be backdated over the time
before it. Not a row per event either, because burn accrues against an envelope
that is held rather than per thing consumed.
Closing a segment is what moves burn into the counters, so a long run lands
incrementally instead of all at the end. Burn that only arrives when a session
stops is burn that cannot refuse the next one, and a bar that does not move
while something is running is a bar nobody believes.
The counters are written with the staleness rule as a single statement: add to
the total if its stamp is still inside the window, otherwise start again from
this amount. Reading and then deciding would be two statements with a gap, and
the gap is where a concurrent tick doubles or vanishes. The first tick for a
team and the thousandth are the same call, for the same reason.
The gate sits at the one moment it is allowed to speak — before a run starts,
never again. A limit refuses the next run and never interrupts one already
going; someone losing a session mid-game to a meter does not come back. Every
window is checked rather than the shortest, because they protect different
things over different spans.
The answer comes back with the created run rather than being thrown away: the
response carries where each window stands, what the account spends per second
now, and what one more run would cost. Every surface that can start a run has
to show that before the click, and a second call for it is a call nobody makes.
Asking twice would also let the number shown and the number billed disagree.
Accrual is wired to the run's own state transition, in the same transaction
that moves it. A session that went live without its meter starting is free
hardware; one that ended without its meter stopping bills forever. Both are
silent, so neither may be a second write that might not happen.
A single secret that turned any request into an operator was the only
credential several routes accepted, and it had no caller left: the device
pairing it existed for is on hold, and nothing in this tree or any client
sent it. What remained was a key that bypassed authentication entirely,
required to boot, and checked by nobody.
Every route behind it had a better answer available:
- Library and game sync move to host credentials. Both took a `userId` in
the body, which meant one secret could write into anybody's library. A
host now says which of its enrolled users a batch is for, and that claim
is checked against the Steam sign-ins it actually holds — one box carries
several people's accounts, so the pair is the unit.
- Download-state reporting narrows to hosts alone, and the body that could
name a different host is gone. Which host is reporting comes from its own
credentials, and a body that still names one is refused rather than
ignored.
- Linking a Steam account is always for the caller.
- Creating a game by hand is deleted; syncing already upserts the catalogue.
- Reading the waitlist is deleted. Every address on it belongs to someone
who has not agreed to anything, and answering it over HTTP made that list
something a leaked key could drain.
- The pairing-code routes are deleted with the flow they served. The domain
module and its table stay, so returning to it is a route file rather than
a migration.
Nothing in the API now accepts a credential that stands for more than one
caller: every request resolves to a specific user or a specific host, which
is what lets a route say "the caller's own library" and mean it.
BREAKING CHANGE: the `x-nestri-admin-token` header is no longer accepted and
`ADMIN_SHARED_SECRET` is no longer read. `POST /games`, `GET /waitlist` and
the `/pairing-code` routes are gone; `POST /games/sync` and `POST /library/sync`
now require host credentials and take `userId` in the body; `POST /steam/link`
no longer accepts `userId`; `POST /games/download-state` no longer accepts
`hostId`.
