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Slice 5 Work-first Schedule reference workload

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This is the checked PostgreSQL Gate A proof for the source-only preview. It creates a one-time Work Schedule, runs one manual pass, and verifies one immutable occurrence and one accepted Work. It proves durable identity and target acceptance; external provider effects remain governed by the Work registration's provider-safety policy.

Prerequisites

  • PostgreSQL 17.5 through Docker/Testcontainers, or APPSURFACE_POSTGRES_TEST_CONNECTION pointing to PostgreSQL 17.5.
  • A migration-owner applies 0001 through 0004, then runs configure-postgresql-roles.sql with distinct migration-owner, dispatcher, and runtime roles.
  • The Schedule processor receives a dispatcher data source, a separate runtime data source, immutable Work registry, validated PostgreSqlDurableWorkOptions, and PostgreSqlDurableScheduleOptions containing the exact runtime role name.

Run the proof from the repository root:

./Durable/verify-postgresql.sh --quick --schedule

The named test is PostgreSqlDurableScheduleTests.AtWorkSchedule_CapturesOneAnchor_DeduplicatesCreate_AndMaterializesOneWork. It creates an At Schedule with the default QueueOne + RunOnce policies, retries the same create request, and runs one ProcessDueAsync call. Expected durable facts are:

Fact Expected result
Schedule create Created, then Duplicate with the same persisted commit timestamp
Dispatch pass one claimed queue row, one recorded occurrence, one materialized Work target
Ledger one schedule_occurrence row
Work store one accepted Work aggregate
Public snapshot no next occurrence for the terminal one-time Schedule

The provider also checks After and unanchored Every explanation semantics without opening a database. The stored transaction_timestamp() anchor—not caller wall clock and not later Work accepted_at—defines their first due time.

PostgreSqlDurableScheduleTests.EveryQueueOne_CoalescesWhileWorkIsNonTerminal_AndRequeuesWhenWorkBecomesTerminal proves the default QueueOne policy: one active Work target holds the slot, a later nominal instant becomes one coalesced occurrence, and the Work terminal transaction requeues that pending occurrence for the next bounded Schedule pass.

Operating limits

PostgreSqlDurableScheduleProcessRequest.MaximumSchedules defaults to 1 and is limited to 128. A zero-result pass is success. Cancellation is checked before the next dispatch lease, so it never undoes a committed Schedule fact. Do not place an unbounded loop around this API in an HTTP request and do not register a hosted service; that activation boundary remains Slice 6.

Deferred proof

This workload does not claim CronosV1, Flow targets, hosted scheduling, or the five deterministic child-process crash barriers. Flow is blocked until its start operation accepts a caller-owned transaction; Cron requires a pinned evaluator and time-zone compatibility proof. Those gates must pass before the increment is called full Slice 5 completion.