The chain lives on the bus alone: the store's tables of builds, rollouts and assignments are dropped (design 47 milestone 5, delivery 2: issues 1094, 1108, 1109, 1110, 1096, 1111)
#381
Merged
mesh-toolsmerged 13 commits from feat/chain-on-the-bus-d2 into main2026-10-18 12:30:43 +00:00
mesh/merge-gate head 68db18bdfc1b merged into trunk da6d038e07c0 — pass: builds build-agent, mesh-controller → ace, g14, novox, shanks; no bus step; every …
The merge gate raises the snapshot's mesh in a throwaway store and now gives it a chain in memory, since the chain lives only on the bus. A module with no commit is carried by no send (a send is read from the commits on the assignments' keys), so the grants step flags only a module with a commit as newly assigned. The tests that sent a module with no build record one, the merge test waits for the merges' consumer before publishing and for the last look of a window before the next test, the pending test follows a chain that deletes nothing, and a wait's settling is a value of its key.
mesh/merge-gate head cbc6bac8c070 merged into trunk da6d038e07c0 — error: builds build-agent, mesh-controller → ace, g14, novox, shanks; no bus step; the m…
mesh/repo-check head cbc6bac8c070 merged into trunk da6d038e07c0 — fail: its merge-check.sh failed: --- FAIL: TestTheGrantsStepSendsTheUserListAndNothingEl…
The fixtures' fresh chain writes the layout marker, as the controller's start leaves a mesh, so the gate stays for the live start. A pending wait that ended unanswered is carried by the next one, so both are known. A hand send forgets what each assignment runs, so the test writes its build and commit after the send.
mesh/merge-gate head 0b4cd46b3f04 merged into trunk da6d038e07c0 — error: builds build-agent, mesh-controller → ace, g14, novox, shanks; no bus step; the m…
mesh/repo-check head 0b4cd46b3f04 merged into trunk da6d038e07c0 — fail: its merge-check.sh failed: --- FAIL: TestAnAssignmentThatBlocksAnotherMachineSaysW…
The live start recorded its layout in chain_moved, so the marker is missing and the layout runs once more over the old keys. It wrote newest, worked, held, commit and source over the pointers of every build made since. Pointers are now made only where missing, and a record already under its new key is not read again.
Delivery 2 deleted the move and chain_moved, so the layout of the builds under their modules is made by the controller's start (LayBuildsOut), recorded by the key layout.done in the builds bucket, retried every half minute with an urgent condition while it fails; the chain on the bus is refused until it exists. Its source readers use the module and pointer reads.
A found ended or pending key is skipped and a pulled-in key is created only where no key exists. RecordSentWith and RecordSentUnder set sent_builds = null in their own update of the node row, so a machine delivery 2 has sent is never copied afterwards. These two updates and the copy's own null are the only writes to the column.
Delivery 1 wrote no commit on the key of a pulled-in module, so after the upgrade those modules fell out of SentBuilds. At the start of the lease holder a copy fills every key that names no commit (creating a standing pulled-in key where none stands), overwrites nothing, empties each column it copied, and raises an urgent condition while it fails. Migration 0105 no longer drops node.sent_builds (issue 1112 does).
The migration raises first unless chain_moved names builds, rollouts and assignments for every kind that holds rows, and unless pending_assignment holds no open or unanswered row; then it drops build_request, build, batched_merge, release_plan, pending_assignment, assignment, raise_assignment_generation(), node.sent_builds and chain_moved. build_gate stays.
Every method of builds, build requests, rollouts, merges and assignments reads and writes the chain alone: the else branches that read the tables, the movers and MoveChain with their tests, chain_moved reads, ChainReads and the flags that switched a kind, the store's assignments mirror (KeepAssignmentPlans needs none of it: it uses only the AssignmentMirrored type, mirrors.go, and AssignmentValues, provisioning.go) and its tick, the move code of the controller's start, and ForTest's chain_moved row. The listed store tests of the move go with their functions; the tests of the readers, requests, assignments and plans that lived beside them stay in chain_store_test.go. Tests that replayed old data migrations over the build, assignment and pin tables are removed with the tables. The static test that no plan is written but through SavePlansMoving now reads the plan's chain path.
SentBuilds answers from the keys of the node's assignments that name a commit, known when the node was sent anything and no key says its commit unknown. A send that names its builds writes the commit, build and rollout on each carried module's key (a module nothing assigns gets a standing key marked pulled-in, never a state) and clears what every other key of the node named; a send by hand writes sent-unknown, a time, on every key and clears their commits. A failed write of these fails the record of the send. node.sent_builds is no longer written. The plan pass ends a pulled-in key only when no send carries it.
A wait that ended unmade and whose condition nobody answered is carried by the wait that replaces it, so the operator is never left without the condition for a module still not on its machine, and taking it back, its condition and the orphan sweep read it there. The condition id stays node.module.<id> with the string id. clearOrphaned says a taken-back wait too. TestAnAssignmentWaitingForItsBuildIsOneKeyOfTheAssignmentsBucket enters through the assign verb and reads the key before and after the build's outcome.
A wait for a build is the value of <node>.<module> with state pending and a pending object (id p-<unix nanoseconds>, a string), so every reader that skips a value with a state skips it, and the controller's own lists skip it through Stands. The transitions are compare-and-set on the key's revision (claim, release, settle, repoint, mark); assigning over a wait carries it into the value that stands, applied when it was waiting; a plan pass never overwrites it; one open wait per machine and module, and a key that holds the module refuses a new one. The table is no longer read or written, ForgetEndedPending is gone (no key is removed), and a wait of a machine the store dropped is none. Callers change type only; their conditions are the next issue.
jschoubben