Both `IDriver` members had no production call site. Their only consumer was
`MemoryTracking`, deleted with the driver-tier recycle machinery in #522, and
`GetMemoryFootprint`'s doc-comment claimed "polled every 30s by Core" — which
had not been true since v3, even before #522 removed the poller.
Owner decision on #525 was (a) delete rather than (b) build the process-wide
watchdog that would consume them. The driver-side implementations are in git
history and were mostly reusable; what was always missing is the trigger, and a
member nobody calls is how the misleading doc-comment survived this long.
Removed from `IDriver`, all 12 driver implementations, and every test stub —
plus the support code that existed only to feed them, which is the part a
member-only deletion would have left behind as dead weight:
- MTConnect's three per-entry byte-weight constants, its cached
`ProbeModelDataItemCount`, and `CountDataItems` — a full device-tree walk run
on every cache fill to populate a number with no remaining reader.
- OpcUaClient's `_discoveredNodeCount` field and the discovery-pass write to it.
- MQTT's `ApproxBytesPerAuthoredTag`.
Two behavioural notes, neither a change in what the software does:
- `AbCipTemplateCache` now has no production reset path. Its only caller was
AB CIP's flush, which itself had no caller — so nothing changes except how
visible the fact is. Recorded on the type, along with the correction that its
comment's claim about a device `ReinitializeAsync` also flushing it was never
true. A UDT redefined on a live controller keeps its stale shape until the
driver instance is rebuilt.
- MTConnect's `/probe` cache is still dropped, by `InvalidateProbeModel()` on an
Agent restart. That is now `internal` rather than `private` so the tests which
used the flush purely to empty the cache drive the real path instead — they
now cover a case that actually occurs in production. Several unrelated doc
comments cited `FlushOptionalCachesAsync` as the canonical CAS example and are
repointed to it.
Tests: the ones that existed only to assert on the removed members are deleted
(3 OpcUaClient, 3 Galaxy, 2 MQTT, 1 MTConnect, 1 AbCip). Worth noting one was
vacuous — `FlushOptionalCachesAsync_resets_footprint_counter` asserted a
footprint of 0 before the flush and 0 after with no discovery in between, so it
would have passed against a flush that did nothing at all.
Full suite green except 7 failures verified identical on master before and
after (4 AbLegacy integration with the compose profile down, 3
Host.IntegrationTests), checked by name rather than assumed.
Docs corrected where they described this as live: `DriverLifecycle.md` (which
carried the #525 placeholder), `drivers/AbCip.md`, `drivers/AbLegacy.md`, and
`v2/driver-stability.md` — whose "polls this every 30 s" + per-driver
`DriverConfig` memory budget were never built as written and are now banner-ed
as design intent rather than description.
Claude-Session: https://claude.ai/code/session_015p7wGqy3YpZNCpDzTpGMKo
`Driver.Sql.Browser` referenced the runtime `Driver.Sql` project. The AdminUI
references that browser, so the whole SQL driver runtime — and
`ZB.MOM.WW.OtOpcUa.Core` through it — sat in the AdminUI's build/deploy graph.
This is the same layering violation #512 removed from the MQTT browser, in a
second driver, and it is why #512's expected removal of `Core.dll` from the
AdminUI's output did not happen.
MEASURED, both directions, on a clean AdminUI build:
before: ZB.MOM.WW.OtOpcUa.Core.dll + ZB.MOM.WW.OtOpcUa.Driver.Sql.dll present
after: both absent
The old csproj comment's premise was sound and survives — the dialect's catalog
SQL *is* the browse engine, so it must be shared rather than duplicated. What
was wrong was the conclusion that sharing it required referencing the runtime
driver. `ISqlDialect`/`SqlServerDialect` depend on nothing in `Driver.Sql`, so
they move to a `.Dialect` leaf that both consume.
This is the `.Transport` shape, not the cheap one: `ISqlDialect` exposes
`DbProviderFactory` and `SqlServerDialect` returns `SqlClientFactory.Instance`,
so `.Contracts` (deliberately provider-free) cannot hold them. Assembly name is
`.Dialect`; the NAMESPACE stays `ZB.MOM.WW.OtOpcUa.Driver.Sql`, matching the
`Driver.Mqtt.Transport` precedent — the extraction cost zero `using` changes.
Two dependencies the cut edge surfaced as the implicit ones they were:
- The AdminUI itself read `SqlDriver.DriverTypeName` in three places — the tag
editor map, the tag config validator, and the Sql address picker. All three
now read `DriverTypeNames.Sql`, which is exactly what that constant resolves
to and exactly the repoint `SqlDriverBrowser`'s own comment had deferred
until a factory was registered against the shared constant. One exists now.
- `SqlDriverFormContractTests` asserts the AdminUI form's emitted JSON against
the runtime factory that reads it, so it genuinely needs the runtime driver.
`AdminUI.Tests` now references it explicitly. A test project referencing a
runtime driver is fine — tests are not in the AdminUI's deploy graph.
New guard: `DriverBrowserLayeringTests` (Commons.Tests) scans the csproj graph
of every `*.Browser` project in the tree, transitively. It reads csproj files
rather than loaded assemblies because the cost is a build-graph cost — the
compiler emits no assembly reference for an unused `ProjectReference`, so
`MqttBrowserLayeringTests`' assembly-reference approach cannot see that case.
The two are complementary and each now points at the other.
Falsified three ways, each red then green again: the direct reference re-added
to the browser; the same reference one hop out via `.Dialect` (proving the walk
is really transitive); and both controls — browsers-discovered and
references-parsed — which exist so an empty discovery cannot pass the absence
assertion vacuously.
#526's claim that the reference "carries no comment at all" was wrong; it
carried a detailed one from the scaffold commit. Corrected on the issue and in
the design doc's project table, which had recorded the deviation as deliberate.
Claude-Session: https://claude.ai/code/session_015p7wGqy3YpZNCpDzTpGMKo
Task 9: DiscoverTreeAsync UntilStable settle loop (FOCAS) — re-capture on a 1s interval until
the node set is non-empty and stable across two passes, bounded by open-timeout; on
timeout with a prior non-empty capture, return it (best-effort) instead of failing.
Task 11: BrowserSessionService resolves bespoke-first, falls back to IUniversalDriverBrowser
when no bespoke browser matches and CanBrowse is true; new CanBrowse on the service.
16 unit tests green (4 settle + 12 service).
Joseph Doherty