Schedule tick loses timestamp precision and delays due SQLite schedules

[rmcdaniel]

Defect

On SQLite, ScheduleManager::tick() can miss a schedule during its exact due second. With a once-per-minute trigger this delays dispatch by one full minute and turns the original occurrence into backfill.

WorkflowSchedule persists next_fire_at with six fractional digits (Y-m-d H:i:s.u). The due query passes now() as a DateTime binding; Laravel's connection grammar serializes it to whole seconds. SQLite compares its stored timestamps as text, so 2026-01-01 12:00:00.000000 is greater than 2026-01-01 12:00:00.

Confirmed on current main / Workflow 2.0.11 with PHP 8.4 and Laravel 13: a persisted/reloaded schedule due exactly at frozen 2026-01-01 12:00:00.000000 UTC yields an empty tick instead of a start. The current implementation is also present in 2.0.9. No lost workflow data was observed; this is late dispatch.

Acceptance

• Use the model's persisted timestamp precision for the due predicate without changing global connection date serialization.
• Test exact whole-second equality, exact fractional equality, elapsed time within the same second, and a future fractional deadline that must not start early.
• Verify original occurrence identity, at-most-one dispatch on repeated ticks, and existing namespace fairness/overlap behavior.
• Qualify SQLite plus supported MySQL/PostgreSQL behavior; publish the fix and inspect affected downstream consumers before marking delivery complete.

A focused regression is being added to V2ScheduleTest; no scheduler replacement, polling-frequency workaround or protocol change is needed.

[rmcdaniel]

Fix merged in #506 at 98d9058. Full main CI has passed its MySQL, PostgreSQL, MariaDB, Laravel upgrade, coverage, quality and regression-corpus jobs; local SQLite schedule/degraded-mode/command qualification passed 89 tests / 452 assertions. Publication and affected-consumer qualification remain next, so this issue stays open until delivery.

[rmcdaniel]

Downstream inspection: Server pins Workflow 2.0.11 and needs a dependency update plus image release; Sample App locks 2.0.11 and needs its embedded dependency/prepared images refreshed. Waterline only has a development-time Workflow dependency, so this fix does not require a Waterline release. SDK/CLI contracts are unchanged. Preparing 2.0.12 metadata and published-package schedule boundary qualification before declaring delivery.

[rmcdaniel]

Published package verified

Workflow 2.0.12, source 3994044, is available on Packagist and GitHub Releases. Release verification passed the published platform contract and all 16 supported Laravel/PHP upgrade journeys.

Clean Composer install qualification finished September 10, 00:09 UTC with PHP 8.4.25, Laravel 13.31.0, Testbench 11.2.0 and PHPUnit 13.3.3. Only the Workflow dependency changed between the old/new package runs; a reflection assertion required ScheduleManager to come from the freshly installed package, not the source checkout.

Published package	SQLite	MySQL 8.0.46	PostgreSQL 16.4
2.0.11 reproduction	Three due cases fail; future case passes	Two fractional due cases fail; whole-second/future pass	Two fractional due cases fail; whole-second/future pass
2.0.12 qualification	89 schedule/degraded-mode/command tests, 452 assertions pass	Seven tick/boundary/fairness tests, 36 assertions pass	Seven tick/boundary/fairness tests, 36 assertions pass

Reused the committed V2ScheduleTest, V2SchedulerDegradedModeTest and V2ScheduleTickCommandTest through a separate Composer project requiring the exact published version. SQLite used fresh PHPUnit processes (--process-isolation); MySQL/PostgreSQL used --filter testTick with their real isolated databases. These checks cover persisted/reloaded fractional timestamps, exact deadline dispatch, original occurrence identity, repeated ticks and future deadlines. The initial PostgreSQL harness lacked its PDO driver; it was corrected before the reported runs. No production or external paid infrastructure was used.

Downstream delivery remains open: Server #156 prepares 2.3.9 / Helm 0.1.88 and passes 131 local command/schedule tests (721 assertions); Sample App #87 updates its embedded package lock and artifact manifest. No unchanged SDK/CLI/Waterline release is required.

[rmcdaniel]

Downstream follow-through: Server 2.3.9 / Helm 0.1.88 are published with Workflow 2.0.12; the downloaded image passed cron/fixed-rate cadence and missed-fire/restart qualification (durable-workflow/server#156). Sample App embedded adoption #87 is published and its prepared images are promoted. The separately pinned service-mode Server adoption is now sample-app#88, with normal CI in progress. This issue remains open until that final example adoption is delivered; no SDK/CLI version-only releases are needed.

[rmcdaniel]

Delivered in Workflow 2.0.12 and Server 2.3.9 / Helm 0.1.88.

• Published-package regression proof reproduces the old boundary failures and passes the fixed SQLite, MySQL and PostgreSQL cases.
• Published upgrade verification passes all 16 Laravel/PHP journeys.
• Published Server qualification passes the selected cron, fixed-rate, missed-fire and restart cases. This is focused schedule coverage, not a claim that every unrelated conformance experiment ran.
• Sample App #87 and #88 deliver the embedded and service-mode dependencies. Main tests, PHP/Python/Rust execution, and both published development-image architectures are qualified.

The sample's auxiliary Python poller also now respects the Server's retryable long-poll backpressure instead of cancelling its activity worker. No SDK/protocol change or version-only SDK release was needed. Closing the scheduler precision defect with downstream delivery complete.