Subscription path online. GalaxyDriver implements ISubscribable; subscribes
batches via gw SubscribeBulkAsync, runs a single shared EventPump consumer
of StreamEventsAsync, fans out OnDataChange events to every driver
subscription that observes the changed gw item handle.
Files:
- Runtime/GalaxySubscriptionHandle.cs — record implementing ISubscriptionHandle.
- Runtime/SubscriptionRegistry.cs — bookkeeping with forward (subscriptionId
→ bindings) and reverse (itemHandle → list of subscriptionIds) maps. The
reverse map is the fan-out index so a single OnDataChange dispatches to
every subscription that observes the changed handle.
- Runtime/IGalaxySubscriber.cs — driver-side seam: SubscribeBulk +
UnsubscribeBulk + StreamEventsAsync. Production wraps GalaxyMxSession;
tests substitute a fake driving synthetic MxEvents.
- Runtime/GatewayGalaxySubscriber.cs — production. Forwards to
MxGatewaySession; bufferedUpdateIntervalMs is captured for now and
becomes a SetBufferedUpdateInterval call once gw issue #102 / gw-9 lands
(PR 6.3 picks this up).
- Runtime/EventPump.cs — long-running background consumer of
StreamEventsAsync. Decodes MxValue + maps quality byte/MxStatusProxy via
StatusCodeMap. Fan-out per subscriber resolves through the registry; bad
handler exceptions are caught + logged, never break the dispatch loop.
Filters out non-OnDataChange families (write-complete and operation-
complete come back via InvokeAsync's reply path, not the event stream).
GalaxyDriver:
- Adds ISubscribable. SubscribeAsync allocates a subscription id,
SubscribeBulks, builds the binding list (failed gw entries get
ItemHandle=0 + a per-tag warn log), registers, and returns the handle.
EventPump is started lazily on first subscribe; one pump per driver
shared across all subscriptions.
- UnsubscribeAsync removes from the registry first (so stale events are
filtered immediately) then calls UnsubscribeBulk best-effort. Foreign
handles throw ArgumentException.
- ReadAsync NotSupportedException message updated: PR 4.4 no longer the
pointer (deferred to a small follow-up that wraps the pump as a
one-shot reader).
- Dispose tears down the pump first, then the repository client, then
clears state.
- Internal ctor extended with optional subscriber parameter.
Tests (15 new, 109 Galaxy total):
- SubscriptionRegistryTests: monotonic id allocation, single+multi
subscription fan-out, failed-handle exclusion, removal isolation, count
invariants.
- GalaxyDriverSubscribeTests: handle allocation + value-change dispatch,
multi-subscription fan-out, failed-tag silence, unsubscribe drops gw
handle and stops dispatch, foreign handle throws, no-subscriber throws,
empty-tag-list returns handle without calling gw.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
