Adds five new MXAccess command kinds (WriteBulk, Write2Bulk,
WriteSecuredBulk, WriteSecured2Bulk, ReadBulk) that ride the existing
"one round-trip, per-entry results" bulk shape used by AddItemBulk and
SubscribeBulk today. MXAccess COM has no native bulk API; the worker
runs each bulk operation as a sequential loop on its STA, returning
one BulkWriteResult / BulkReadResult per requested entry so per-item
MXAccess failures surface as was_successful=false rather than throwing.
ReadBulk has no MXAccess analogue. The worker satisfies it by:
- Returning the last cached OnDataChange payload (was_cached=true)
when the requested tag is already in the session''s item registry
AND advised — the existing subscription is NOT touched, since the
caller did not create it.
- Otherwise taking the AddItem + Advise + wait-for-OnDataChange +
UnAdvise + RemoveItem snapshot lifecycle itself (was_cached=false)
and leaving the session exactly as it was. The wait pumps Windows
messages on the STA so the inbound MXAccess event can dispatch
while the executor still holds the thread.
The new MxAccessValueCache lives on each MxAccessSession, shared with
MxAccessBaseEventSink which populates it on every OnDataChange after
the event clears the outbound queue. Eviction on RemoveItem keeps
reused MXAccess handles from serving stale values from a previous
lifetime.
Gateway-side authorization wires WriteBulk/Write2Bulk to invoke:write,
WriteSecuredBulk/WriteSecured2Bulk to invoke:secure, ReadBulk to
invoke:read. The constraint-filter pipeline is refactored from a single
BulkConstraintPlan record into an abstract base plus three concretes
(SubscribeBulk, WriteBulk, ReadBulk), each owning its own denied-entry
merge so the dispatch site never branches on reply shape. A new
FilterWriteBulkAsync<TEntry> generic over the four write-entry shapes
runs CheckWriteHandleAsync per entry; denied entries surface as the
BulkWriteResult shape, preserving original-index order.
All five language clients (.NET, Go, Rust, Python, Java) gained the
five new methods following their existing bulk pattern, with regenerated
protobufs.
Tests added:
- MxAccessValueCacheTests (6 cases) — Set/TryGet, Remove resets the
version, TryWaitForUpdate signals on Set, pump step fires each poll.
- MxAccessBaseEventSinkTests — OnDataChange populates the cache,
ValueCache property exposes the bound instance.
- MxAccessCommandExecutorTests — four bulk-write variants (per-entry
success/failure, value+timestamp forwarding, secured user ids),
ReadBulk snapshot lifecycle on uncached tag (timeout surfaces as
was_successful=false), invalid-payload reply.
- GatewayGrpcScopeResolverTests — five new MxCommandKind cases.
- SessionManagerTests — WriteBulk and ReadBulk forwarding through
FakeWorkerHarness; ReadBulk forwards timeout_ms.
- Per-client (.NET, Go, Rust, Python, Java) — WriteBulk builds the
right command and returns per-entry results, ReadBulk forwards the
timeout and unpacks the was_cached flag.
Cross-language e2e CLI subcommands for the new bulks are deliberately
scoped out of this change (each of the five client CLIs would need
five new subcommands plus matching phases in
scripts/run-client-e2e-tests.ps1); coverage equivalent to the existing
bulk-subscribe coverage is provided by worker + gateway + per-client
unit tests.
Docs updated in the same commit: gateway.md (Public MXAccess Command
Surface), docs/DesignDecisions.md (new "Bulk Command Family" section
with the ReadBulk cache-then-snapshot rationale), and every client
README.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Joseph Doherty
5e375f6d3d