[FEATURE] Project may be zipped/unzipped

python/core/qgsproject.sip

@@ -612,6 +612,24 @@ Returns the number of registered layers.
  :rtype: QMap<str, QgsMapLayer *>
 %End
 
+    bool unzip( const QString &filename );
+%Docstring
+ Unzip a project
+ \param filename The project filename to unzip
+ :return: true if unzip is well performed, false otherwise
+.. versionadded:: 3.0
+ :rtype: bool
+%End
+
+    bool zip( const QString &filename );
+%Docstring
+ Zip the project
+ \param filename The zip filename
+ :return: true if zip is well performed, false otherwise
+.. versionadded:: 3.0
+ :rtype: bool
+%End
+
 
     QList<QgsMapLayer *> addMapLayers( const QList<QgsMapLayer *> &mapLayers /Transfer/,
                                        bool addToLegend = true);

src/core/CMakeLists.txt

@@ -305,6 +305,7 @@ SET(QGIS_CORE_SRCS
   qgsxmlutils.cpp
   qgssettings.cpp
   qgsstacktrace.cpp
+  qgsarchive.cpp
   qgsziputils.cpp
 
   composer/qgsaddremoveitemcommand.cpp
@@ -893,6 +894,7 @@ SET(QGIS_CORE_HDRS
   qgsvirtuallayerdefinitionutils.h
   qgsmapthemecollection.h
   qgsxmlutils.h
+  qgsarchive.h
   qgsziputils.h
   qgsvector.h
   qgslocalec.h

src/core/qgsarchive.cpp

@@ -0,0 +1,113 @@
+/***************************************************************************
+                            qgsarchive.cpp
+                           ----------------
+
+    begin                : July 07, 2017
+    copyright            : (C) 2017 by Paul Blottiere
+    email                : paul.blottiere@oslandia.com
+ ***************************************************************************/
+
+/***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#include "qgsarchive.h"
+#include "qgsziputils.h"
+#include "qgsmessagelog.h"
+
+QgsArchive::QgsArchive()
+  : mDir( new QTemporaryDir() )
+{
+}
+
+QgsArchive::~QgsArchive()
+{
+}
+
+QString QgsArchive::dir() const
+{
+  return mDir->path();
+}
+
+void QgsArchive::clear()
+{
+  mDir.reset( new QTemporaryDir() );
+  mFilename.clear();
+  mFiles.clear();
+}
+
+bool QgsArchive::zip( const QString &filename )
+{
+  // create a temporary path
+  QTemporaryFile tmpFile;
+  tmpFile.open();
+  tmpFile.close();
+
+  // zip content
+  if ( ! QgsZipUtils::zip( tmpFile.fileName(), mFiles ) )
+  {
+    QString err = QObject::tr( "Unable to zip content" );
+    QgsMessageLog::logMessage( err, QStringLiteral( "QgsArchive" ) );
+    return false;
+  }
+
+  // remove existing zip file
+  if ( QFile::exists( filename ) )
+    QFile::remove( filename );
+
+  // save zip archive
+  if ( ! tmpFile.rename( filename ) )
+  {
+    QString err = QObject::tr( "Unable to save zip file '%1'" ).arg( filename );
+    QgsMessageLog::logMessage( err, QStringLiteral( "QgsArchive" ) );
+    return false;
+  }
+
+  // keep the zip filename
+  tmpFile.setAutoRemove( false );
+  mFilename = filename;
+
+  return true;
+}
+
+bool QgsArchive::unzip( const QString &filename )
+{
+  clear();
+
+  QgsZipUtils::unzip( filename, mDir->path(), mFiles );
+  mFilename = filename;
+
+  return ! projectFile().isEmpty();
+}
+
+void QgsArchive::addFile( const QString &file )
+{
+  mFiles.append( file );
+}
+
+QString QgsArchive::filename() const
+{
+  return mFilename;
+}
+
+QString QgsArchive::projectFile() const
+{
+  Q_FOREACH ( const QString &file, mFiles )
+  {
+    QFileInfo fileInfo( file );
+    if ( "qgs" == fileInfo.suffix().toLower() )
+      return file;
+  }
+
+  return QString();
+}
+
+QStringList QgsArchive::files() const
+{
+  return mFiles;
+}

src/core/qgsarchive.h

@@ -0,0 +1,71 @@
+/***************************************************************************
+                            qgsarchive.h
+                          ----------------
+
+    begin                : July 07, 2017
+    copyright            : (C) 2017 by Paul Blottiere
+    email                : paul.blottiere@oslandia.com
+ ***************************************************************************/
+
+/***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#ifndef QGSARCHIVE_H
+#define QGSARCHIVE_H
+
+#include "qgis_core.h"
+#include <QStringList>
+#include <QTemporaryFile>
+#include <QTemporaryDir>
+#include <memory>
+
+/**
+ * \class QgsArchive
+ * \ingroup core
+ * \brief Class allowing to manage the zip/unzip actions on project
+ * \since QGIS 3.0
+ */
+class CORE_EXPORT QgsArchive
+{
+  public:
+
+    /**
+     * Constructor for QgsArchive
+     */
+    QgsArchive();
+    ~QgsArchive();
+
+    bool zip( const QString &zipFilename );
+
+    bool unzip( const QString &zipFilename );
+
+    void clear();
+
+    void addFile( const QString &filename );
+
+    QString filename() const;
+
+    QString projectFile() const;
+
+    QStringList files() const;
+
+    QString dir() const;
+
+  private:
+    // used when unzip is performed
+    std::unique_ptr<QTemporaryDir> mDir;
+
+    // content of the archive
+    QStringList mFiles;
+
+    // zip filename
+    QString mFilename;
+};
+
+#endif

src/core/qgsproject.cpp

@@ -332,6 +332,7 @@ QgsProject::QgsProject( QObject *parent )
   , mLayoutManager( new QgsLayoutManager( this ) )
   , mRootGroup( new QgsLayerTree )
   , mLabelingEngineSettings( new QgsLabelingEngineSettings )
+  , mArchive( new QgsArchive() )
   , mAutoTransaction( false )
   , mEvaluateDefaultValues( false )
   , mDirty( false )
@@ -2064,6 +2065,81 @@ QList<QgsMapLayer *> QgsProject::mapLayersByName( const QString &layerName ) con
   return mLayerStore->mapLayersByName( layerName );
 }
 
+bool QgsProject::unzip( const QString &filename )
+{
+  clearError();
+  std::unique_ptr<QgsArchive> archive( new QgsArchive() );
+
+  // unzip the archive
+  if ( !archive->unzip( filename ) )
+  {
+    setError( tr( "Unable to unzip file '%1'" ).arg( filename ) );
+    return false;
+  }
+
+  // test if zip provides a .qgs file
+  if ( archive->projectFile().isEmpty() )
+  {
+    setError( tr( "Zip archive does not provide a project file" ) );
+    return false;
+  }
+
+  // read the project file
+  if ( ! read( archive->projectFile() ) )
+  {
+    setError( tr( "Cannot read unzipped qgs project file" ) );
+    return false;
+  }
+
+  // keep the archive
+  mArchive.reset( archive.release() );
+
+  return true;
+}
+
+bool QgsProject::zip( const QString &filename )
+{
+  clearError();
+
+  // save the current project in a temporary .qgs file
+  QgsArchive archive;
+  const QString baseName = QFileInfo( filename ).baseName();
+  const QString qgsFileName = QString( "%1.qgs" ).arg( baseName );
+  QFile qgsFile( QDir( archive.dir() ).filePath( qgsFileName ) );
+
+  bool writeOk;
+  if ( qgsFile.open( QIODevice::WriteOnly ) )
+  {
+    const QString originalFilename = mFile.fileName();
+    mFile.setFileName( qgsFile.fileName() );
+
+    writeOk = write();
+
+    mFile.setFileName( originalFilename );
+    qgsFile.close();
+  }
+
+  // stop here with an error message
+  if ( ! writeOk )
+  {
+    setError( tr( "Unable to write temporary qgs file" ) );
+    return false;
+  }
+
+  // create the archive
+  archive.addFile( qgsFile.fileName() );
+
+  // zip
+  QString errMsg;
+  if ( !archive.zip( filename ) )
+  {
+    setError( tr( "Unable to perform zip" ) );
+    return false;
+  }
+
+  return true;
+}
+
 QList<QgsMapLayer *> QgsProject::addMapLayers(
   const QList<QgsMapLayer *> &layers,
   bool addToLegend,

src/core/qgsproject.h

@@ -40,6 +40,7 @@
 #include "qgsprojectproperty.h"
 #include "qgsmaplayer.h"
 #include "qgsmaplayerstore.h"
+#include "qgsarchive.h"
 
 class QFileInfo;
 class QDomDocument;
@@ -575,6 +576,22 @@ class CORE_EXPORT QgsProject : public QObject, public QgsExpressionContextGenera
      */
     QMap<QString, QgsMapLayer *> mapLayers() const;
 
+    /**
+     * Unzip a project
+     * \param filename The project filename to unzip
+     * \returns true if unzip is well performed, false otherwise
+     * \since QGIS 3.0
+     */
+    bool unzip( const QString &filename );
+
+    /**
+     * Zip the project
+     * \param filename The zip filename
+     * \returns true if zip is well performed, false otherwise
+     * \since QGIS 3.0
+     */
+    bool zip( const QString &filename );
+
 #ifndef SIP_RUN
 
     /** Returns a list of registered map layers with a specified layer type.
@@ -1048,6 +1065,8 @@ class CORE_EXPORT QgsProject : public QObject, public QgsExpressionContextGenera
 
     QVariantMap mCustomVariables;
 
+    std::unique_ptr<QgsArchive> mArchive;
+
     QFile mFile;                 // current physical project file
     mutable QgsProjectPropertyKey mProperties;  // property hierarchy, TODO: this shouldn't be mutable
     QString mTitle;              // project title

src/core/qgsziputils.cpp

@@ -115,13 +115,7 @@ bool QgsZipUtils::unzip( const QString &zipFilename, const QString &dir, QString
 
 bool QgsZipUtils::zip( const QString &zipFilename, const QStringList &files )
 {
-  if ( QFileInfo::exists( zipFilename ) )
-  {
-    QString err = QObject::tr( "Error zip file yet exist: '%1'" ).arg( zipFilename );
-    QgsMessageLog::logMessage( err, QStringLiteral( "QgsZipUtils" ) );
-    return false;
-  }
-  else if ( zipFilename.isEmpty() )
+  if ( zipFilename.isEmpty() )
   {
     QString err = QObject::tr( "Error zip filename is empty" );
     QgsMessageLog::logMessage( err, QStringLiteral( "QgsZipUtils" ) );