Dario Lipicar
664b43f18a
Acquiring a QtRO replica per call (acquireDynamic + waitForSource) is expensive:
under a tight loop — e.g. a proxy forwarding every method to its target, or a UI
backend driving a whole surface — it dominates and can even starve the nested
synchronous calls. Cache the LogosObject handle per object name in m_objectCache
and reuse it across calls (both the sync invokeRemoteMethod and the async
invokeRemoteMethodAsync paths); no per-call release(). A stale handle (source
went away — module unloaded / transport dropped) is detected via a new
LogosObject::isValid() (QtRO replica state == Valid) and transparently
re-acquired. The cache is released in clearObjectCache() from the destructor and
before reconnect().
- logos_object.h: add virtual bool isValid() (default true).
- qt_remote/remote_transport.{h,cpp}: RemoteLogosObject::isValid() (replica
Valid state) + a process-wide acquireCount() test hook.
- logos_api_consumer.{h,cpp}: m_objectCache + acquireCachedObject()/
clearObjectCache(); sync + async reuse the cached handle; async keeps the
QPointer guard and never releases the shared handle from its callback.
Test: RemoteEventTest.ConsumerReusesCachedHandleAcrossSyncAndAsyncCalls publishes
a provider over the qt_remote host, does 12 sync + 12 async echo calls, and
asserts every result is correct AND acquireCount() == 1 (one replica for all 24
calls). 164/164 green.
logos-protocol
The Logos protocol layer: transports, token exchange, and the
language-neutral lp_* C ABI (cpp/logos_protocol.h) that every Logos
SDK builds on.
Extracted from logos-cpp-sdk so that non-C++ SDKs (Rust, …) consume the
same transports, capability/token flow and wire behavior through one stable,
versioned boundary instead of re-wrapping the C++/Qt SDK.
What lives here
- Public C ABI —
cpp/logos_protocol.h: consumer surface (lp_client_*,lp_invoke[_async],lp_subscribe, tokens,lp_get_methods), provider groundwork (lp_provider_*), and the protocol version (LOGOS_PROTOCOL_VERSION_*,lp_protocol_version(),lp_protocol_abi_major()). JSON-in-strings data model; bytes cross the boundary as{"_bytes":"<base64url>"}(lossless, NUL-safe). - Transports — plain TCP / TCP+TLS (Boost.Asio + OpenSSL + nlohmann,
Qt-free),
qt_local, in-memory mock, and Qt Remote Objects (qt_remote— the only Qt-bearing transport). - Consumer core —
LogosAPIClient/LogosAPIConsumerincluding the automaticcapability_module.requestModuletoken-fetch flow (behind the protocol boundary: every language gets it for free). - Provider-side plumbing —
ModuleProxy(auth gate the transports publish) and the abstractLogosProviderObjectinterface (logos_provider_interface.h). - Token manager, transport/registry factories, mode config (remote/local/mock), and the canonical QVariant↔JSON conversion used at the QRO boundary.
logos-cpp-sdk layers the typed C++ developer API (LogosAPI, module
context, code generator, provider base classes) on top of this repo.
Versioning
This repo carries the logos-protocol semver — the single number that governs Logos load/call compatibility. Two participants (modules, hosts, SDKs in any language) interoperate iff they share the same MAJOR. MINOR is additive/back-compatible; PATCH never affects compatibility. SDKs must re-expose the version of the protocol they linked (never mint their own).
Building
# Via workspace
ws build logos-protocol
# Standalone
nix build
# Tests
nix build .#tests
Layering invariant
logos-protocol depends only on Qt / Boost / OpenSSL / nlohmann_json — it
must NEVER depend on logos-cpp-sdk, logos-qt-sdk, logos-rust-sdk, liblogos
or logos-lidl. Everything points inward.