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#include "genericresource.h"
#include "entitybuffer.h"
#include "pipeline.h"
#include "queuedcommand_generated.h"
#include "createentity_generated.h"
#include "domainadaptor.h"
#include "commands.h"
#include "clientapi.h"
#include "index.h"
#include "log.h"
#include <assert.h>
using namespace Akonadi2;
/**
* Drives the pipeline using the output from all command queues
*/
class Processor : public QObject
{
Q_OBJECT
public:
Processor(Akonadi2::Pipeline *pipeline, QList<MessageQueue*> commandQueues)
: QObject(),
mPipeline(pipeline),
mCommandQueues(commandQueues),
mProcessingLock(false)
{
for (auto queue : mCommandQueues) {
const bool ret = connect(queue, &MessageQueue::messageReady, this, &Processor::process);
Q_UNUSED(ret);
}
}
signals:
void error(int errorCode, const QString &errorMessage);
private:
bool messagesToProcessAvailable()
{
for (auto queue : mCommandQueues) {
if (!queue->isEmpty()) {
return true;
}
}
return false;
}
private slots:
void process()
{
if (mProcessingLock) {
return;
}
mProcessingLock = true;
auto job = processPipeline().then<void>([this]() {
mProcessingLock = false;
if (messagesToProcessAvailable()) {
process();
}
}).exec();
}
KAsync::Job<void> processQueuedCommand(const Akonadi2::QueuedCommand *queuedCommand)
{
Log() << "Processing command: " << Akonadi2::Commands::name(queuedCommand->commandId());
//Throw command into appropriate pipeline
switch (queuedCommand->commandId()) {
case Akonadi2::Commands::DeleteEntityCommand:
//mPipeline->removedEntity
return KAsync::null<void>();
case Akonadi2::Commands::ModifyEntityCommand:
//mPipeline->modifiedEntity
return KAsync::null<void>();
case Akonadi2::Commands::CreateEntityCommand:
return mPipeline->newEntity(queuedCommand->command()->Data(), queuedCommand->command()->size());
default:
return KAsync::error<void>(-1, "Unhandled command");
}
return KAsync::null<void>();
}
//Process all messages of this queue
KAsync::Job<void> processQueue(MessageQueue *queue)
{
//TODO use something like:
//KAsync::foreach("pass iterator here").each("process value here").join();
//KAsync::foreach("pass iterator here").parallel("process value here").join();
return KAsync::dowhile(
[this, queue](KAsync::Future<bool> &future) {
if (queue->isEmpty()) {
future.setValue(false);
future.setFinished();
return;
}
queue->dequeue(
[this, &future](void *ptr, int size, std::function<void(bool success)> messageQueueCallback) {
auto callback = [messageQueueCallback, &future](bool success) {
messageQueueCallback(success);
future.setValue(!success);
future.setFinished();
};
flatbuffers::Verifier verifyer(reinterpret_cast<const uint8_t *>(ptr), size);
if (!Akonadi2::VerifyQueuedCommandBuffer(verifyer)) {
Warning() << "invalid buffer";
callback(false);
return;
}
auto queuedCommand = Akonadi2::GetQueuedCommand(ptr);
Trace() << "Dequeued Command: " << Akonadi2::Commands::name(queuedCommand->commandId());
//TODO JOBAPI: job lifetime management
//Right now we're just leaking jobs. In this case we'd like jobs that are heap allocated and delete
//themselves once done. In other cases we'd like jobs that only live as long as their handle though.
//FIXME this job is stack allocated and thus simply dies....
processQueuedCommand(queuedCommand).then<void>(
[callback]() {
callback(true);
},
[callback](int errorCode, QString errorMessage) {
Warning() << "Error while processing queue command: " << errorMessage;
callback(false);
}
).exec();
},
[&future](const MessageQueue::Error &error) {
Warning() << "Error while getting message from messagequeue: " << error.message;
future.setValue(false);
future.setFinished();
}
);
}
);
}
KAsync::Job<void> processPipeline()
{
//Go through all message queues
auto it = QSharedPointer<QListIterator<MessageQueue*> >::create(mCommandQueues);
return KAsync::dowhile(
[it]() { return it->hasNext(); },
[it, this](KAsync::Future<void> &future) {
auto queue = it->next();
processQueue(queue).then<void>([&future]() {
Trace() << "Queue processed";
future.setFinished();
}).exec();
}
);
}
private:
Akonadi2::Pipeline *mPipeline;
//Ordered by priority
QList<MessageQueue*> mCommandQueues;
bool mProcessingLock;
};
GenericResource::GenericResource(const QByteArray &resourceIdentifier)
: Akonadi2::Resource(),
mUserQueue(QStandardPaths::writableLocation(QStandardPaths::GenericDataLocation) + "/akonadi2/storage", "org.kde." + resourceIdentifier + ".userqueue"),
mSynchronizerQueue(QStandardPaths::writableLocation(QStandardPaths::GenericDataLocation) + "/akonadi2/storage", "org.kde." + resourceIdentifier + ".synchronizerqueue"),
mError(0)
{
}
GenericResource::~GenericResource()
{
}
void GenericResource::configurePipeline(Akonadi2::Pipeline *pipeline)
{
//TODO figure out lifetime of the processor
mProcessor = new Processor(pipeline, QList<MessageQueue*>() << &mUserQueue << &mSynchronizerQueue);
QObject::connect(mProcessor, &Processor::error, [this](int errorCode, const QString &msg) { onProcessorError(errorCode, msg); });
}
void GenericResource::onProcessorError(int errorCode, const QString &errorMessage)
{
Warning() << "Received error from Processor: " << errorCode << errorMessage;
mError = errorCode;
}
int GenericResource::error() const
{
return mError;
}
void GenericResource::enqueueCommand(MessageQueue &mq, int commandId, const QByteArray &data)
{
//TODO get rid of m_fbb member variable
m_fbb.Clear();
auto commandData = Akonadi2::EntityBuffer::appendAsVector(m_fbb, data.constData(), data.size());
auto buffer = Akonadi2::CreateQueuedCommand(m_fbb, commandId, commandData);
Akonadi2::FinishQueuedCommandBuffer(m_fbb, buffer);
mq.enqueue(m_fbb.GetBufferPointer(), m_fbb.GetSize());
}
void GenericResource::processCommand(int commandId, const QByteArray &data, uint size, Akonadi2::Pipeline *pipeline)
{
//TODO instead of copying the command including the full entity first into the command queue, we could directly
//create a new revision, only pushing a handle into the commandqueue with the relevant changeset (for changereplay).
//The problem is that we then require write access from multiple threads (or even processes to avoid sending the full entity over the wire).
enqueueCommand(mUserQueue, commandId, data);
}
KAsync::Job<void> GenericResource::processAllMessages()
{
//We have to wait for all items to be processed to ensure the synced items are available when a query gets executed.
//TODO: report errors while processing sync?
//TODO JOBAPI: A helper that waits for n events and then continues?
return KAsync::start<void>([this](KAsync::Future<void> &f) {
if (mSynchronizerQueue.isEmpty()) {
f.setFinished();
} else {
QObject::connect(&mSynchronizerQueue, &MessageQueue::drained, [&f]() {
f.setFinished();
});
}
}).then<void>([this](KAsync::Future<void> &f) {
if (mUserQueue.isEmpty()) {
f.setFinished();
} else {
QObject::connect(&mUserQueue, &MessageQueue::drained, [&f]() {
f.setFinished();
});
}
});
}
#include "genericresource.moc"
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