Files
logos-cpp-sdk/cpp/module_proxy.cpp
T
Igor SirotinandClaude Opus 4.7 d77c3dd616 fix: marshal provider events onto the source thread (#68)
* fix: marshal provider events onto the source thread

ModuleProxy's event listener emitted eventResponse directly on whatever thread
the module fired the event from (its worker/FFI thread). QtRemoteObjects then
serialized and sent the event from that foreign thread, racing the source
socket against a method reply being sent from the source thread, which silently
dropped the reply.

This is why a method that emits an event mid-call never returns to the caller
(e.g. delivery_module start(), which emits connectionStateChanged as the node
connects) while a method that emits nothing (createNode) returns fine.

Marshal the emission onto the ModuleProxy's own thread via a queued invocation
so events and method replies are serialized on the single thread
QtRemoteObjects expects to own the source.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* docs: generalize the threading comment

* fix: use AutoConnection so same-thread emits stay synchronous

QueuedConnection deferred every emission, breaking same-thread callers that
emit-then-assert and crashing when a queued lambda outlived the object.
AutoConnection invokes synchronously when already on the source thread and only
queues cross-thread emissions (the actual fix); passing 'this' as context
cancels a queued call if the object is destroyed first.

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-25 09:35:25 -04:00

94 lines
3.3 KiB
C++

#include "module_proxy.h"
#include "logos_provider_object.h"
#include <QDebug>
ModuleProxy::ModuleProxy(LogosProviderObject* provider, QObject* parent)
: QObject(parent)
, m_provider(provider)
{
if (m_provider) {
m_provider->setEventListener([this](const QString& eventName, const QVariantList& data) {
qDebug() << "[LogosProviderObject] ModuleProxy: forwarding event" << eventName << "as Qt signal";
// Events may be fired from any thread (e.g. a module's worker/FFI
// thread), but this object is the QtRemoteObjects source and must be
// driven from its own thread. Emitting directly from a foreign
// thread runs QtRO's source serialization there, racing the source
// socket against a reply being sent from the source thread, which
// can silently drop the reply. AutoConnection keeps same-thread
// callers synchronous (the common case) and only queues the
// emission when it arrives from another thread, so events and
// replies stay serialized on the thread QtRO expects to own the
// source. Passing `this` as the context also cancels a queued
// emission if this object is destroyed first.
QMetaObject::invokeMethod(this, [this, eventName, data]() {
emit eventResponse(eventName, data);
}, Qt::AutoConnection);
});
qDebug() << "[LogosProviderObject] ModuleProxy: created, wrapping LogosProviderObject"
<< m_provider->providerName();
}
}
ModuleProxy::~ModuleProxy()
{
qDebug() << "ModuleProxy: destroyed";
}
bool ModuleProxy::saveToken(const QString& from_module_name, const QString& token)
{
if (from_module_name.isEmpty()) {
qWarning() << "ModuleProxy: Cannot save token with empty module name";
return false;
}
if (token.isEmpty()) {
qWarning() << "ModuleProxy: Cannot save empty token for module:" << from_module_name;
return false;
}
m_tokens[from_module_name] = token;
qDebug() << "ModuleProxy: Token saved for module:" << from_module_name;
return true;
}
QVariant ModuleProxy::callRemoteMethod(const QString& authToken, const QString& methodName, const QVariantList& args)
{
if (!m_provider) {
qWarning() << "ModuleProxy: Cannot call method on null provider:" << methodName;
return QVariant();
}
if (methodName.isEmpty()) {
qWarning() << "ModuleProxy: Method name cannot be empty";
return QVariant();
}
if (methodName == "getPluginMethods" && args.isEmpty()) {
return QVariant(getPluginMethods());
}
qDebug() << "ModuleProxy: callRemoteMethod" << methodName << "args:" << args;
return m_provider->callMethod(methodName, args);
}
bool ModuleProxy::informModuleToken(const QString& authToken, const QString& moduleName, const QString& token)
{
Q_UNUSED(authToken)
if (!m_provider) {
qWarning() << "ModuleProxy: Cannot inform token on null provider";
return false;
}
return m_provider->informModuleToken(moduleName, token);
}
QJsonArray ModuleProxy::getPluginMethods()
{
if (!m_provider) return QJsonArray();
qDebug() << "[LogosProviderObject] ModuleProxy: calling LogosProviderObject::getMethods()";
return m_provider->getMethods();
}
#include "moc_module_proxy.cpp"