[FEATURE][composer] Allow remote urls to be entered as picture path

nyalldawson · nyalldawson · commit 9d1822013805 · 2014-08-19T21:35:14.000+10:00
for picture items, and automatically fetch them. Sponsored by the
City of Uster, Switzerland.
diff --git a/python/core/composer/qgscomposerpicture.sip b/python/core/composer/qgscomposerpicture.sip
@@ -44,16 +44,38 @@ class QgsComposerPicture: QgsComposerItem
      * @param path full path to the source image
      * @see usePictureExpression
      * @see pictureFile
+     * @deprecated use setPicturePath instead
     */
-    void setPictureFile( const QString& path );
+    void setPictureFile( const QString& path ) /Deprecated/;
 
     /**Returns the path of the source image file. Data defined picture source may override
      * this value.
      * @returns path to the source image
      * @see usePictureExpression
      * @see setPictureFile
+     * @deprecated use picturePath instead  
     */
-    QString pictureFile() const;
+    QString pictureFile() const /Deprecated/;
+    
+     /**Sets the source path of the image (may be svg or a raster format). Data defined
+     * picture source may override this value. The path can either be a local path
+     * or a remote (http) path.
+     * @param path path for the source image
+     * @see usePictureExpression
+     * @see picturePath
+     * @note added in QGIS 2.5
+    */
+    void setPicturePath( const QString& path );
+
+    /**Returns the path of the source image. Data defined picture source may override
+     * this value. The path can either be a local path or a remote (http) path.
+     * @returns path for the source image
+     * @see usePictureExpression
+     * @see setPicturePath
+     * @note added in QGIS 2.5
+    */
+    QString picturePath() const;    
+
 
     /**Sets this items bound in scene coordinates such that 1 item size units
      * corresponds to 1 scene size unit and resizes the svg symbol / image
diff --git a/src/app/composer/qgscomposerpicturewidget.cpp b/src/app/composer/qgscomposerpicturewidget.cpp
@@ -114,7 +114,7 @@ void QgsComposerPictureWidget::on_mPictureBrowseButton_clicked()
   if ( mPicture )
   {
     mPicture->beginCommand( tr( "Picture changed" ) );
-    mPicture->setPictureFile( filePath );
+    mPicture->setPicturePath( filePath );
     mPicture->update();
     mPicture->endCommand();
   }
@@ -130,7 +130,7 @@ void QgsComposerPictureWidget::on_mPictureLineEdit_editingFinished()
     QFileInfo fileInfo( filePath );
 
     mPicture->beginCommand( tr( "Picture changed" ) );
-    mPicture->setPictureFile( filePath );
+    mPicture->setPicturePath( filePath );
     mPicture->update();
     mPicture->endCommand();
   }
@@ -156,7 +156,7 @@ void QgsComposerPictureWidget::on_mPreviewListWidget_currentItemChanged( QListWi
 
   QString absoluteFilePath = current->data( Qt::UserRole ).toString();
   mPicture->beginCommand( tr( "Picture changed" ) );
-  mPicture->setPictureFile( absoluteFilePath );
+  mPicture->setPicturePath( absoluteFilePath );
   mPictureLineEdit->setText( absoluteFilePath );
   mPicture->update();
   mPicture->endCommand();
@@ -382,7 +382,7 @@ void QgsComposerPictureWidget::setGuiElementValues()
     mResizeModeComboBox->blockSignals( true );
     mAnchorPointComboBox->blockSignals( true );
 
-    mPictureLineEdit->setText( mPicture->pictureFile() );
+    mPictureLineEdit->setText( mPicture->picturePath() );
     mPictureRotationSpinBox->setValue( mPicture->pictureRotation() );
 
     refreshMapComboBox();
diff --git a/src/core/composer/qgscomposerpicture.cpp b/src/core/composer/qgscomposerpicture.cpp
@@ -25,13 +25,17 @@
 #include "qgsvectorlayer.h"
 #include "qgsmessagelog.h"
 #include "qgsdatadefined.h"
+#include "qgsnetworkcontentfetcher.h"
 #include <QDomDocument>
 #include <QDomElement>
 #include <QFileInfo>
 #include <QImageReader>
 #include <QPainter>
 #include <QSvgRenderer>
-
+#include <QNetworkRequest>
+#include <QNetworkReply>
+#include <QEventLoop>
+#include <QCoreApplication>
 
 QgsComposerPicture::QgsComposerPicture( QgsComposition *composition ) :
     QgsComposerItem( composition ),
@@ -268,20 +272,17 @@ QRect QgsComposerPicture::clippedImageRect( double &boundRectWidthMM, double &bo
       break;
   }
 
-
   return QRect( leftClip, topClip, boundRectWidthPixels, boundRectHeightPixels );
-
 }
 
 void QgsComposerPicture::setPictureFile( const QString& path )
 {
-  mSourceFile.setFileName( path );
-  refreshPicture();
+  setPicturePath( path );
 }
 
 void QgsComposerPicture::refreshPicture()
 {
-  QString source = mSourceFile.fileName();
+  QString source = mSourcePath;
 
   //data defined source set?
   mHasExpressionError = false;
@@ -301,25 +302,55 @@ void QgsComposerPicture::refreshPicture()
     }
   }
 
-  QFile path;
-  path.setFileName( source );
-  loadPicture( path );
+  loadPicture( source );
 }
 
-void QgsComposerPicture::loadPicture( const QFile& file )
+void QgsComposerPicture::loadRemotePicture( const QString &url )
 {
-  if ( !file.exists() )
+  //remote location
+
+  QgsNetworkContentFetcher fetcher;
+  //pause until HTML fetch
+  mLoaded = false;
+  fetcher.fetchContent( QUrl( url ) );
+  connect( &fetcher, SIGNAL( finished() ), this, SLOT( remotePictureLoaded() ) );
+
+  while ( !mLoaded )
+  {
+    qApp->processEvents();
+  }
+
+  QNetworkReply* reply = fetcher.reply();
+  if ( reply )
+  {
+    QImageReader imageReader( reply );
+    mImage = imageReader.read();
+    mMode = RASTER;
+    reply->deleteLater();
+  }
+  else
+  {
+    mMode = Unknown;
+  }
+}
+
+void QgsComposerPicture::loadLocalPicture( const QString &path )
+{
+  QFile pic;
+  pic.setFileName( path );
+
+  if ( !pic.exists() )
   {
     mMode = Unknown;
   }
   else
   {
-    QFileInfo sourceFileInfo( file );
+    QFileInfo sourceFileInfo( pic );
     QString sourceFileSuffix = sourceFileInfo.suffix();
     if ( sourceFileSuffix.compare( "svg", Qt::CaseInsensitive ) == 0 )
     {
       //try to open svg
-      mSVG.load( file.fileName() );
+      mSVG.load( pic.fileName() );
       if ( mSVG.isValid() )
       {
         mMode = SVG;
@@ -335,7 +366,7 @@ void QgsComposerPicture::loadPicture( const QFile& file )
     else
     {
       //try to open raster with QImageReader
-      QImageReader imageReader( file.fileName() );
+      QImageReader imageReader( pic.fileName() );
       if ( imageReader.read( &mImage ) )
       {
         mMode = RASTER;
@@ -347,11 +378,30 @@ void QgsComposerPicture::loadPicture( const QFile& file )
     }
   }
 
+}
+
+void QgsComposerPicture::remotePictureLoaded()
+{
+  mLoaded = true;
+}
+
+void QgsComposerPicture::loadPicture( const QString &path )
+{
+  if ( path.startsWith( "http" ) )
+  {
+    //remote location
+    loadRemotePicture( path );
+  }
+  else
+  {
+    //local location
+    loadLocalPicture( path );
+  }
   if ( mMode != Unknown ) //make sure we start with a new QImage
   {
     recalculateSize();
   }
-  else if ( mHasExpressionError || !( file.fileName().isEmpty() ) )
+  else if ( mHasExpressionError || !( path.isEmpty() ) )
   {
     //trying to load an invalid file or bad expression, show cross picture
     mMode = SVG;
@@ -589,7 +639,18 @@ void QgsComposerPicture::setPictureExpression( QString expression )
 
 QString QgsComposerPicture::pictureFile() const
 {
-  return mSourceFile.fileName();
+  return picturePath();
+}
+
+void QgsComposerPicture::setPicturePath( const QString &path )
+{
+  mSourcePath = path;
+  refreshPicture();
+}
+
+QString QgsComposerPicture::picturePath() const
+{
+  return mSourcePath;
 }
 
 bool QgsComposerPicture::writeXML( QDomElement& elem, QDomDocument & doc ) const
@@ -599,7 +660,7 @@ bool QgsComposerPicture::writeXML( QDomElement& elem, QDomDocument & doc ) const
     return false;
   }
   QDomElement composerPictureElem = doc.createElement( "ComposerPicture" );
-  composerPictureElem.setAttribute( "file", QgsProject::instance()->writePath( mSourceFile.fileName() ) );
+  composerPictureElem.setAttribute( "file", QgsProject::instance()->writePath( mSourcePath ) );
   composerPictureElem.setAttribute( "pictureWidth", QString::number( mPictureWidth ) );
   composerPictureElem.setAttribute( "pictureHeight", QString::number( mPictureHeight ) );
   composerPictureElem.setAttribute( "resizeMode", QString::number(( int )mResizeMode ) );
@@ -668,8 +729,7 @@ bool QgsComposerPicture::readXML( const QDomElement& itemElem, const QDomDocumen
     setDataDefinedProperty( QgsComposerObject::PictureSource, expressionActive, true, sourceExpression, QString() );
   }
 
-  QString fileName = QgsProject::instance()->readPath( itemElem.attribute( "file" ) );
-  mSourceFile.setFileName( fileName );
+  mSourcePath = QgsProject::instance()->readPath( itemElem.attribute( "file" ) );
 
   //picture rotation
   if ( itemElem.attribute( "pictureRotation", "0" ).toDouble() != 0 )
diff --git a/src/core/composer/qgscomposerpicture.h b/src/core/composer/qgscomposerpicture.h
@@ -67,16 +67,37 @@ class CORE_EXPORT QgsComposerPicture: public QgsComposerItem
      * @param path full path to the source image
      * @see usePictureExpression
      * @see pictureFile
+     * @deprecated use setPicturePath instead
     */
-    void setPictureFile( const QString& path );
+    Q_DECL_DEPRECATED void setPictureFile( const QString& path );
 
     /**Returns the path of the source image file. Data defined picture source may override
      * this value.
      * @returns path to the source image
      * @see usePictureExpression
      * @see setPictureFile
+     * @deprecated use picturePath instead
     */
-    QString pictureFile() const;
+    Q_DECL_DEPRECATED QString pictureFile() const;
+
+    /**Sets the source path of the image (may be svg or a raster format). Data defined
+     * picture source may override this value. The path can either be a local path
+     * or a remote (http) path.
+     * @param path path for the source image
+     * @see usePictureExpression
+     * @see picturePath
+     * @note added in QGIS 2.5
+    */
+    void setPicturePath( const QString& path );
+
+    /**Returns the path of the source image. Data defined picture source may override
+     * this value. The path can either be a local path or a remote (http) path.
+     * @returns path for the source image
+     * @see usePictureExpression
+     * @see setPicturePath
+     * @note added in QGIS 2.5
+    */
+    QString picturePath() const;
 
     /**Sets this items bound in scene coordinates such that 1 item size units
      * corresponds to 1 scene size unit and resizes the svg symbol / image
@@ -284,7 +305,7 @@ class CORE_EXPORT QgsComposerPicture: public QgsComposerItem
 
     QImage mImage;
     QSvgRenderer mSVG;
-    QFile mSourceFile;
+    QString mSourcePath;
     Mode mMode;
 
     QSize mDefaultSvgSize;
@@ -302,9 +323,10 @@ class CORE_EXPORT QgsComposerPicture: public QgsComposerItem
     QgsComposerItem::ItemPositionMode mPictureAnchor;
 
     bool mHasExpressionError;
+    bool mLoaded;
 
     /**loads an image file into the picture item and redraws the item*/
-    void loadPicture( const QFile &file );
+    void loadPicture( const QString &path );
 
     /**sets up the picture item and connects to relevant signals*/
     void init();
@@ -313,6 +335,18 @@ class CORE_EXPORT QgsComposerPicture: public QgsComposerItem
      * anchor settings
     */
     QRect clippedImageRect( double &boundRectWidthMM, double &boundRectHeightMM, QSize imageRectPixels );
+
+    /**Loads a remote picture for the item
+    */
+    void loadRemotePicture( const QString &url );
+
+    /**Loads a local picture for the item
+    */
+    void loadLocalPicture( const QString &path );
+
+  private slots:
+
+    void remotePictureLoaded();
 };
 
 #endif
diff --git a/tests/src/core/testqgscomposerpicture.cpp b/tests/src/core/testqgscomposerpicture.cpp
diff --git a/tests/testdata/control_images/expected_composerpicture_remote/expected_composerpicture_remote.png b/tests/testdata/control_images/expected_composerpicture_remote/expected_composerpicture_remote.png
