Commit Graph

4 Commits

Author SHA1 Message Date
Kgothatso Ngako
98f766fcd3 fix: put the invite in the room, so a stuck one can be seen
Inviting a member to a group that already had members put nothing whatsoever in
the transcript. Not "put it in late" -- nothing, and nothing ever if the invite
did not complete. So the one failure the user is best placed to notice, an
invite that never reached the person it was made for, was the one the app kept
to itself.

The line existed. It was written by `MarmotOutboundDao.deliveryWelcome`, which
is the wrong place for it, and the reason is the two paths through
`inviteMember` that docs/marmot-membership.md already describes. A group that is
still only its creator has nobody to inform, so its Welcome goes out immediately
and `deliveryWelcome` runs inside the invite. A group that has members must
broadcast a commit first, and its Welcome waits for a relay to acknowledge it --
`DatabaseNostrRepository.broadcastProcessed` picks the stored `MarmotCommitResult`
back up and delivers then. Every invite after a group's first therefore wrote
its transcript line a relay round trip away from the invite, if at all.

**Four separate silences, not one.** Worth listing because only the first is
about the deferral, and fixing that alone would have left the other three:

1. The deferred path wrote nothing until the ack, and nothing ever without one.
2. The write hung off `getMarmotKeyPackageById(...)?.let { getProfileByPublicKey(...)?.let { ... } }`.
   Those two lookups were there to *name* the invitee, and a miss on either cost
   the whole line rather than just the name.
3. `deliveryWelcome` wraps its body in `catch (e: Throwable) { logger.e(...) }`
   and returned Unit, so a Welcome that could not be built reached the log and
   no further.
4. `inviteMemberToChatRoom` is `@Transaction`. An invite that threw -- no MLS
   state for the room, a credential identity that does not match the peer --
   rolled its line back with everything else, which is right, and left no
   account of the refusal anywhere durable.

And the line it did write was `messageType = "message"`, `isUserMessage = true`,
so it rendered as a chat bubble: "Invited Bob to chat", attributed to the
inviter as something they said.

**Three membership types, and the line moves to invite time.**
`ChatMessage.MEMBERSHIP_TYPES` -- `memberInvited`, `memberInviteSent`,
`memberInviteFailed` -- rendered by the transcript as system notices through
`RitualNotice`, the way the ceremony, signing and chronicle lines already are.

`memberInvited` is written by `inviteMember` and by `addMembersToChatRoom`'s
batch path, *when the invite is made*, and deliberately **inside** the caller's
transaction. Both halves of that matter and they pull opposite ways: written any
later and an invite waiting on an ack that never comes shows nothing, which is
the bug; written outside the transaction and an invite that does not survive
`addMember` leaves the room claiming one was made.

`memberInviteSent` is written by `DatabaseNostrRepository` alone. It is not
written on the immediate path, and that is not an oversight: there the Welcome
goes out in the same breath as the invite, so one line is the whole truth. It
would also be a line the transcript could not order -- `MantraConverters` stores
`Instant` as `epochSeconds`, the room query is `ORDER BY createdAt DESC`, and two
rows written in the same second tie. Only the deferred path separates the two
events in time, so only it owes a second line.

`memberInviteFailed` carries the reason, because it is the only copy the user
gets. `deliveryWelcome` now returns `Boolean` and files this line from its own
catch before returning false -- its callers had no other way to see a failure it
had already swallowed, and on the deferred path there is no invite screen left
to fail back to. `addMembersToChatRoom` reads that answer instead of a
`runCatching` that could never catch anything.

**The refusal is written from outside the transaction that rolled it back.**
`DatabaseChatRepository.inviteMember` catches, calls `announceInviteFailed`, and
rethrows. The throw is what puts a message on the invite screen now; the line is
what is still there tomorrow. Swallowing it instead would have popped the user
back to the chat as though the invite had gone out, which is the bug the
existing `runCatching` in `AddMemberToChatRoomConfirmationViewModel` was added
to stop.

**No schema change.** `messageType` is a free-form string column with a default,
so new values need no migration -- unlike the chronicle rename, which had to
rewrite the ones already stored. Nothing reindexes these either: they carry no
`marmotGroupEventId`, so `getResolvedMarmotGroupEventIds` cannot see them and
`UNRESOLVED_MARMOT_TYPES` does not name them.

Six new tests. Four on the DAO: the immediate path leaves a line naming the
invitee where the old code left none, the deferred path leaves one *and* claims
no Welcome sent before any ack, everything an invite writes is a membership type
rather than something the transcript would render as a bubble, and a refused
invite leaves no claim that one was made. Two new ones on
`DatabaseChatRepository`, which had no test file: a refused invite is written
into the room, and the caller still gets the throw.

Still open, and now said plainly in the doc rather than implied: a Participant
row carries no state saying where its invite got to. The transcript narrates it;
the `TODO: Update status of participant Invitation.PENDING -> Invitation.SENT`
is untouched. Nor does an invitee with no published key package reach the room
at all -- that fails in the view model, before there is an invite to write a
line about.

806 tests pass -- 509 jvm, 297 android.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-06 18:16:26 +02:00
Kgothatso Ngako
3dea07135c fix: add a group's whole membership in one commit, closing the epoch race
`MarmotOutboundDao.addMembersToChatRoom` stages every member with `proposeAdd` and
issues a single `commit()`. Both callers that know their membership up front now
use it: `SelectChatRoomTypeViewModel.inviteMembers` at room creation, and
`DkgRitualViewModel.inviteAdmins` for the #admins room.

Inviting one at a time created an epoch per member, and each of those commits
raced the previous member's welcome. MarmotInboundManager refuses future-epoch
messages outright, on both wire formats, with no queue and no replay -- so the
member who lost that race was silently stuck an epoch behind while the caller saw
a successful invite. Deriving isOneMemberInitialGroupCreation narrowed that window;
this removes it. No member ever has to process a commit for an epoch they were not
yet in, so there is no longer a race to lose.

One commit yields one welcome: `buildWelcome` emits an EncryptedGroupSecrets per
added member and each joiner finds its own entry by key package reference. The blob
is shared, delivery stays per peer, because each welcome event is tagged with that
peer's key package.

## Why this needed no schema change

Batching at creation time means the single commit happens while the group is still
only its creator, which takes the immediate-welcome branch: nothing is broadcast
and MarmotCommitResult is never written. The bookkeeping that assumes one peer per
commit is simply not on this path.

So the batch is taken only when `members().size == 1`, and anything else falls back
to inviting sequentially -- correct, if not ideal. Batching into an established
group would take the deferred branch, where `peerKeyPackageEventId` is singular and
the ack-triggered delivery in DatabaseNostrRepository expects one welcome; making
that work needs a list there and a fan-out on acknowledgement. Nothing currently
adds several members to an established group, so that is left outstanding and
documented rather than speculatively built.

The group state is persisted after `commit()` and before any welcome goes out, so a
crash between them leaves the group at the epoch the welcomes describe rather than
one behind it.

## Reporting

Members with no published key package still cannot be added -- a Marmot invite
needs one -- and are now returned alongside any that failed to receive their
welcome, rather than the two being conflated. Both still only reach the log; the
coordinator is not yet told.

docs/marmot-membership.md is updated in the same change: batching moves from
outstanding work to described behaviour, with the schema constraint that shapes it
and the remaining fan-out work recorded. The note about sequential invites is
narrowed to where they still happen.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-05 15:02:06 +02:00
Kgothatso Ngako
8fc1c9e650 fix: stop deferring the first invitee's welcome behind a commit nobody needs
`inviteMember` now works out for itself whether the group it is adding to has
anybody to inform:

    val isOneMemberInitialGroupCreation = mlsGroup.members().size == 1

read before `addMember` advances the tree. The parameter is gone from the
signature and no caller passes it any more.

Callers were the wrong place for this decision and both of them got it wrong.
`inviteMemberToChatRoom` hardcoded `false`, and `ChatRepository.inviteMember` did
not expose it at all, so every invite made through a group -- room creation in
SelectChatRoomTypeViewModel, and the #admins room -- took the deferred-welcome
path. That includes the first invite, when the group is still only its creator, at
which point:

  - the commit has no audience. No other member exists, and nobody outside the
    group can decrypt it, so it is noise on the relay.
  - the welcome is then withheld until a relay acknowledges that noise. If the ack
    never lands, the first invitee receives nothing at all.

Only createMlsDirectMessageChatRoom passed `true`, and only because a DM has
exactly one invite. A group of n has one such invite too -- the first -- and it was
not getting it.

The condition is right at any size, not just for DMs: "the group has nobody to
inform" is true exactly once. Invite two sees one member who must advance, invite
three sees two, and so on. Their commits are encrypted with
`commitResult.preCommitExporterSecret`, the epoch the earlier invitees received in
their own welcome, so they can decrypt and advance. `members()` skips empty leaves,
so this also stays correct for a group that has had members removed.

## What this does and does not fix

It removes a pointless commit and, with DefaultDMRelayList now a single relay, a
single point of failure sitting in front of every group's first member.

It also narrows a silent race rather than closing it. MarmotInboundManager refuses
future-epoch messages outright on both wire formats -- no queue, no replay -- so a
commit arriving before its recipient's welcome is dropped and that member never
advances, while the coordinator sees a successful invite. Previously both commits
went out before either welcome; now welcome 1 is sent before commit 2 exists, so
the first invitee is already at the right epoch. For n >= 3 the window between
welcome 1 and commit 2 remains.

Closing it needs the adds batched into one commit, which is the outstanding work
described in docs/marmot-membership.md. That doc is updated here to describe the
derived flag as current behaviour rather than a proposal, and to keep batching as
the remaining item.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-05 14:44:28 +02:00
Kgothatso Ngako
b99cb8fcd5 docs: write down the shared-key subsystem and how Marmot membership fails
First docs in the repo -- README.md is still the stock KMP template. Three
documents plus an index, covering the parts whose behaviour is not recoverable by
reading the code: where the reasoning lives in a protocol, where a failure mode is
silent, or where a decision looked arbitrary and was not.

marmot-membership.md is the one that earns its place. Everything about adding a
member compiles, the invite reports success, and a member simply never appears --
and the reason is never in the invite code. It records that
inviteMemberToChatRoom hardcodes isOneMemberInitialGroupCreation = false and that
ChatRepository does not expose it, so every group invite takes the deferred-welcome
path including the first, when the group is still just its creator and the commit
has no audience at all. Then why that is silent rather than noisy:
MarmotInboundManager refuses future-epoch messages outright, on both wire formats,
with no queue and no replay, so a commit arriving before its recipient's welcome
is dropped and that member never advances. EPOCH_RETENTION_WINDOW retains past
epochs and does nothing for messages from ahead. Three options are set out with the
per-invite correctness table, including the honest limit that the recommended one
narrows the race without closing it.

shared-key-derivation.md argues why the paths are not BIP32 -- no chain code
exists, hardened derivation is impossible rather than unimplemented, and a FROST
tweak takes the scalar as input so the chain code leaves the problem entirely. It
records the x-only serialisation trap avoided by choosing the scalar directly, and
states the rule that must not be broken: never reconstruct a derived key in the
clear, because k = k' - t hands over the group key rather than one derived key.

shared-key-ceremony.md covers the seven kinds, the three approval gates and why
the coordinator's aggregations are deliberately not among them, faults as values
rather than exceptions, and the transcript's idempotency-by-construction. It also
writes down the invariant that produces no error when broken: pendingApproval must
mirror the gates in advance, or the screen offers an approval that does nothing --
or none while the ritual sits still.

Every factual claim was checked against the source rather than recalled, which
turned up one correction worth having: there are two future-epoch refusals, for
PrivateMessage and for Commit, so the drop covers both wire formats and not just
one.

Each document leads with the failure mode rather than the architecture, on the
grounds that a failure is what sends somebody to docs in the first place, and each
lists its known gaps -- including that none of this has run on a physical device.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-05 14:39:19 +02:00