Introduced a QueryRunner object

The QueryRunner object lives for the duration of the query (so just
for the initial query for non-live queries, and for the lifetime of the
result model for live queries).
It's supposed to handle all the threading internally and decouple the
lifetime of the facade.

1 files changed, 107 insertions, 0 deletions

diff --git a/common/queryrunner.h b/common/queryrunner.h
new file mode 100644
index 0000000..e2af9de
--- /dev/null
+++ b/common/queryrunner.h
@@ -0,0 +1,107 @@
+/*
+    Copyright (c) 2015 Christian Mollekopf <mollekopf@kolabsys.com>
+
+    This library is free software; you can redistribute it and/or modify it
+    under the terms of the GNU Library General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or (at your
+    option) any later version.
+
+    This library is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
+    License for more details.
+
+    You should have received a copy of the GNU Library General Public License
+    along with this library; see the file COPYING.LIB.  If not, write to the
+    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+    02110-1301, USA.
+*/
+
+#pragma once
+
+#include <QObject>
+#include "facadeinterface.h"
+#include "resourceaccess.h"
+#include "resultprovider.h"
+#include "domaintypeadaptorfactoryinterface.h"
+#include "storage.h"
+#include "query.h"
+
+/**
+ * A QueryRunner runs a query and updates the corresponding result set.
+ * 
+ * The lifetime of the QueryRunner is defined by the resut set (otherwise it's doing useless work),
+ * and by how long a result set must be updated. If the query is one off the runner dies after the execution,
+ * otherwise it lives on the react to changes and updates the corresponding result set.
+ * 
+ * QueryRunner has to keep ResourceAccess alive in order to keep getting updates.
+ */
+
+class QueryRunnerBase : public QObject
+{
+    Q_OBJECT
+protected:
+    typedef std::function<KAsync::Job<void>()> QueryFunction;
+
+    /**
+     * Set the query to run
+     */
+    void setQuery(const QueryFunction &query)
+    {
+        queryFunction = query;
+    }
+
+
+protected slots:
+    /**
+     * Rerun query with new revision
+     */
+    void revisionChanged(qint64 newRevision)
+    {
+        Trace() << "New revision: " << newRevision;
+        run().exec();
+    }
+
+private:
+    /**
+     * Starts query
+     */
+    KAsync::Job<void> run(qint64 newRevision = 0)
+    {
+        return queryFunction();
+    }
+
+    QueryFunction queryFunction;
+};
+
+template<typename DomainType>
+class QueryRunner : public QueryRunnerBase
+{
+public:
+    QueryRunner(const Akonadi2::Query &query, const Akonadi2::ResourceAccessInterface::Ptr &, const QByteArray &instanceIdentifier, const DomainTypeAdaptorFactoryInterface::Ptr &, const QByteArray &bufferType);
+
+    typename Akonadi2::ResultEmitter<typename DomainType::Ptr>::Ptr emitter();
+
+private:
+    static void replaySet(ResultSet &resultSet, Akonadi2::ResultProviderInterface<typename DomainType::Ptr> &resultProvider);
+
+    void readEntity(const Akonadi2::Storage::NamedDatabase &db, const QByteArray &key, const std::function<void(const Akonadi2::ApplicationDomain::ApplicationDomainType::Ptr &, Akonadi2::Operation)> &resultCallback);
+
+    ResultSet loadInitialResultSet(const Akonadi2::Query &query, Akonadi2::Storage::Transaction &transaction, QSet<QByteArray> &remainingFilters);
+    ResultSet loadIncrementalResultSet(qint64 baseRevision, const Akonadi2::Query &query, Akonadi2::Storage::Transaction &transaction, QSet<QByteArray> &remainingFilters);
+
+    ResultSet filterSet(const ResultSet &resultSet, const std::function<bool(const Akonadi2::ApplicationDomain::ApplicationDomainType::Ptr &domainObject)> &filter, const Akonadi2::Storage::NamedDatabase &db, bool initialQuery);
+    std::function<bool(const Akonadi2::ApplicationDomain::ApplicationDomainType::Ptr &domainObject)> getFilter(const QSet<QByteArray> remainingFilters, const Akonadi2::Query &query);
+    qint64 load(const Akonadi2::Query &query, const std::function<ResultSet(Akonadi2::Storage::Transaction &, QSet<QByteArray> &)> &baseSetRetriever, Akonadi2::ResultProviderInterface<typename DomainType::Ptr> &resultProvider, bool initialQuery);
+    qint64 executeIncrementalQuery(const Akonadi2::Query &query, Akonadi2::ResultProviderInterface<typename DomainType::Ptr> &resultProvider);
+    qint64 executeInitialQuery(const Akonadi2::Query &query, const typename DomainType::Ptr &parent, Akonadi2::ResultProviderInterface<typename DomainType::Ptr> &resultProvider);
+
+private:
+    QSharedPointer<Akonadi2::ResultProvider<typename DomainType::Ptr> > mResultProvider;
+    QSharedPointer<Akonadi2::ResourceAccessInterface> mResourceAccess;
+    DomainTypeAdaptorFactoryInterface::Ptr mDomainTypeAdaptorFactory;
+    QByteArray mResourceInstanceIdentifier;
+    QByteArray mBufferType;
+    Akonadi2::Query mQuery;
+};
+