[ExternalStorage] Add widget to configure/edit and visualize external…

… storage

python/gui/auto_generated/editorwidgets/core/qgswidgetwrapper.sip.in

@@ -51,7 +51,8 @@ changed status of the widget will be saved.
     enum Property
     {
       RootPath,
-      DocumentViewerContent
+      DocumentViewerContent,
+      StorageUrl
     };
 
     static const QgsPropertiesDefinition &propertyDefinitions();

python/gui/auto_generated/qgsexternalresourcewidget.sip.in

@@ -133,6 +133,55 @@ is set to :py:class:`QgsFileWidget`.RelativeDefaultPath.
 %Docstring
 Configures the base path which should be used if the relativeStorage property
 is set to :py:class:`QgsFileWidget`.RelativeDefaultPath.
+%End
+
+    void setStorageType( const QString &storageType );
+%Docstring
+Set ``storageType`` storage type unique identifier as defined in :py:class:`QgsExternalStorageRegistry` or
+null QString if there is no storage defined, only file selection.
+
+.. seealso:: :py:func:`storageType`
+
+.. versionadded:: 3.22
+%End
+
+    QString storageType() const;
+%Docstring
+Get storage type unique identifier as defined in :py:class:`QgsExternalStorageRegistry`.
+Returns null QString if there is no storage defined, only file selection.
+
+.. seealso:: :py:func:`setStorageType`
+
+.. versionadded:: 3.22
+%End
+
+    void setStorageAuthConfigId( const QString &authCfg );
+%Docstring
+Sets the authentication configuration ID to be used for the current external storage (if
+defined)
+
+.. versionadded:: 3.22
+%End
+
+    const QString &storageAuthConfigId() const;
+%Docstring
+Returns the authentication configuration ID used for the current external storage (if defined)
+
+.. versionadded:: 3.22
+%End
+
+    void setMessageBar( QgsMessageBar *messageBar );
+%Docstring
+Set ``messageBar`` to report messages
+
+.. versionadded:: 3.22
+%End
+
+    QgsMessageBar *messageBar() const;
+%Docstring
+Returns message bar used to report messages
+
+.. versionadded:: 3.22
 %End
 
   signals:

python/gui/auto_generated/qgsfilewidget.sip.in

@@ -9,6 +9,8 @@
 
 
 
+
+
 class QgsFileWidget : QWidget
 {
 %Docstring(signature="appended")
@@ -75,6 +77,104 @@ Sets the current file ``path``.
     void setReadOnly( bool readOnly );
 %Docstring
 Sets whether the widget should be read only.
+%End
+
+    void setStorageType( const QString &storageType );
+%Docstring
+Set ``storageType`` storage type unique identifier as defined in :py:class:`QgsExternalStorageRegistry` or
+null QString if there is no storage defined.
+If no external storage has been defined, QgsFileWidget will only update file path according to
+selected files.
+
+.. seealso:: :py:func:`storageType`
+
+.. versionadded:: 3.22
+%End
+
+    QString storageType() const;
+%Docstring
+Get storage type unique identifier as defined in :py:class:`QgsExternalStorageRegistry`.
+Returns null QString if there is no storage defined, only file selection.
+
+.. seealso:: :py:func:`setStorageType`
+
+.. versionadded:: 3.22
+%End
+
+    QgsExternalStorage *externalStorage() const;
+%Docstring
+Returns external storage used to store selected file names, None if none have been defined.
+If no external storage has been defined, QgsFileWidget will only update file path according to
+selected files.
+
+.. seealso:: :py:func:`setStorageType`
+
+.. versionadded:: 3.22
+%End
+
+    void setStorageAuthConfigId( const QString &authCfg );
+%Docstring
+Sets the authentication configuration ID to be used for the current external storage (if
+defined)
+
+.. versionadded:: 3.22
+%End
+
+    const QString &storageAuthConfigId() const;
+%Docstring
+Returns the authentication configuration ID used for the current external storage (if defined)
+
+.. versionadded:: 3.22
+%End
+
+    void setStorageUrlExpression( const QString &urlExpression );
+%Docstring
+Set ``urlExpression`` expression, which once evaluated, provide the URL used to store selected
+documents. This is used only if an external storage has been defined
+
+.. seealso:: :py:func:`setStorageType`
+
+.. versionadded:: 3.22
+%End
+
+    QString storageUrlExpressionString() const;
+%Docstring
+Returns the original, unmodified expression string, which once evaluated, provide the
+URL used to store selected documents. This is used only if an external storage has been defined.
+Returns null if no expression has been set.
+
+.. seealso:: :py:func:`setStorageUrlExpression`
+
+.. versionadded:: 3.22
+%End
+
+    QgsExpression *storageUrlExpression() const;
+%Docstring
+Returns expression, which once evaluated, provide the URL used to store selected
+documents. This is used only if an external storage has been defined.
+Returns null if no expression has been set.
+
+.. seealso:: :py:func:`setStorageUrlExpression`
+
+.. versionadded:: 3.22
+%End
+
+    void setExpressionContext( const QgsExpressionContext &context );
+%Docstring
+Set expression context to be used when for storage URL expression evaluation
+
+.. seealso:: :py:func:`setStorageUrlExpression`
+
+.. versionadded:: 3.22
+%End
+
+    const QgsExpressionContext &expressionContext() const;
+%Docstring
+Returns expression context used for storage url expression evaluation
+
+.. seealso:: :py:func:`storageUrlExpression`
+
+.. versionadded:: 3.22
 %End
 
     QString dialogTitle() const;
@@ -250,6 +350,26 @@ Returns a pointer to the widget's line edit, which can be used to customize
 the appearance and behavior of the line edit portion of the widget.
 
 .. versionadded:: 3.0
+%End
+
+    void setMessageBar( QgsMessageBar *messageBar );
+%Docstring
+Set ``messageBar`` to report messages
+
+.. versionadded:: 3.22
+%End
+
+    QgsMessageBar *messageBar() const;
+%Docstring
+Returns message bar used to report messages
+
+.. versionadded:: 3.22
+%End
+
+    static QgsExpressionContextScope *createFileWidgetScope();
+%Docstring
+Creates and Returns an expression context scope specific to QgsFileWidget
+It defines the variable containing the user selected file name
 %End
 
   signals:

src/gui/editorwidgets/core/qgseditorwidgetregistry.cpp

@@ -63,7 +63,7 @@ void QgsEditorWidgetRegistry::initEditors( QgsMapCanvas *mapCanvas, QgsMessageBa
   registerWidget( QStringLiteral( "Color" ), new QgsColorWidgetFactory( tr( "Color" ) ) );
   registerWidget( QStringLiteral( "RelationReference" ), new QgsRelationReferenceFactory( tr( "Relation Reference" ), mapCanvas, messageBar ) );
   registerWidget( QStringLiteral( "DateTime" ), new QgsDateTimeEditFactory( tr( "Date/Time" ) ) );
-  registerWidget( QStringLiteral( "ExternalResource" ), new QgsExternalResourceWidgetFactory( tr( "Attachment" ) ) );
+  registerWidget( QStringLiteral( "ExternalResource" ), new QgsExternalResourceWidgetFactory( tr( "Attachment" ), messageBar ) );
   registerWidget( QStringLiteral( "KeyValue" ), new QgsKeyValueWidgetFactory( tr( "Key/Value" ) ) );
   registerWidget( QStringLiteral( "List" ), new QgsListWidgetFactory( tr( "List" ) ) );
   registerWidget( QStringLiteral( "Binary" ), new QgsBinaryWidgetFactory( tr( "Binary (BLOB)" ), messageBar ) );

src/gui/editorwidgets/core/qgswidgetwrapper.cpp

@@ -28,7 +28,8 @@ const QgsPropertiesDefinition &QgsWidgetWrapper::propertyDefinitions()
     properties =
     {
       { RootPath, QgsPropertyDefinition( "propertyRootPath", QgsPropertyDefinition::DataTypeString, QObject::tr( "Root path" ), QObject::tr( "string of variable length representing root path to attachment" ) ) },
-      { DocumentViewerContent, QgsPropertyDefinition( "documentViewerContent", QgsPropertyDefinition::DataTypeString, QObject::tr( "Document viewer content" ), QObject::tr( "string" ) + "<b>NoContent</b>|<b>Image</b>|<b>Web</b>" ) }
+      { DocumentViewerContent, QgsPropertyDefinition( "documentViewerContent", QgsPropertyDefinition::DataTypeString, QObject::tr( "Document viewer content" ), QObject::tr( "string" ) + "<b>NoContent</b>|<b>Image</b>|<b>Web</b>" ) },
+      { StorageUrl, QgsPropertyDefinition( "storageUrl", QgsPropertyDefinition::DataTypeString, QObject::tr( "Storage Url" ), QObject::tr( "String of variable length representing the URL used to store document with an external storage" ) ) }
     };
   }
   return properties;

src/gui/editorwidgets/core/qgswidgetwrapper.h

@@ -76,7 +76,8 @@ class GUI_EXPORT QgsWidgetWrapper : public QObject
     enum Property
     {
       RootPath = 0, //!< Root path for external resource
-      DocumentViewerContent //!< Document type for external resource
+      DocumentViewerContent, //!< Document type for external resource
+      StorageUrl //!< Storage URL for external resource
     };
 
     /**

src/gui/editorwidgets/qgsexternalresourceconfigdlg.cpp

@@ -22,8 +22,12 @@
 #include "qgsvectorlayer.h"
 #include "qgspropertyoverridebutton.h"
 #include "qgseditorwidgetwrapper.h"
+#include "qgsexternalstorage.h"
+#include "qgsexternalstorageregistry.h"
+#include "qgsexpressioncontextutils.h"
 
 #include <QFileDialog>
+#include <QComboBox>
 
 class QgsExternalResourceWidgetWrapper;
 
@@ -32,6 +36,20 @@ QgsExternalResourceConfigDlg::QgsExternalResourceConfigDlg( QgsVectorLayer *vl,
 {
   setupUi( this );
 
+  mStorageType->addItem( tr( "Select existing file" ), QString() );
+  for ( QgsExternalStorage *storage : QgsApplication::externalStorageRegistry()->externalStorages() )
+  {
+    mStorageType->addItem( tr( "Store with %1" ).arg( storage->type() ), storage->type() );
+  }
+
+  mExternalStorageGroupBox->setVisible( false );
+
+  initializeDataDefinedButton( mStorageUrlPropertyOverrideButton, QgsEditorWidgetWrapper::StorageUrl );
+  mStorageUrlPropertyOverrideButton->registerVisibleWidget( mStorageUrlExpression );
+  mStorageUrlPropertyOverrideButton->registerExpressionWidget( mStorageUrlExpression );
+  mStorageUrlPropertyOverrideButton->registerVisibleWidget( mStorageUrl, false );
+  mStorageUrlPropertyOverrideButton->registerExpressionContextGenerator( this );
+
   // By default, uncheck some options
   mUseLink->setChecked( false );
   mFullUrl->setChecked( false );
@@ -69,6 +87,7 @@ QgsExternalResourceConfigDlg::QgsExternalResourceConfigDlg( QgsVectorLayer *vl,
   mRelativeButtonGroup->setId( mRelativeDefault, QgsFileWidget::RelativeDefaultPath );
   mRelativeProject->setChecked( true );
 
+  connect( mStorageType, static_cast<void ( QComboBox::* )( int )>( &QComboBox::currentIndexChanged ), this, &QgsExternalResourceConfigDlg::changeStorageType );
   connect( mFileWidgetGroupBox, &QGroupBox::toggled, this, &QgsEditorConfigWidget::changed );
   connect( mFileWidgetButtonGroupBox, &QGroupBox::toggled, this, &QgsEditorConfigWidget::changed );
   connect( mFileWidgetFilterLineEdit, &QLineEdit::textChanged, this, &QgsEditorConfigWidget::changed );
@@ -82,6 +101,7 @@ QgsExternalResourceConfigDlg::QgsExternalResourceConfigDlg( QgsVectorLayer *vl,
   { mDocumentViewerContentSettingsWidget->setEnabled( ( QgsExternalResourceWidget::DocumentViewerContent )idx != QgsExternalResourceWidget::NoContent ); } );
   connect( mDocumentViewerHeight, static_cast<void ( QSpinBox::* )( int )>( &QSpinBox::valueChanged ), this, &QgsEditorConfigWidget::changed );
   connect( mDocumentViewerWidth, static_cast<void ( QSpinBox::* )( int )>( &QSpinBox::valueChanged ), this, &QgsEditorConfigWidget::changed );
+  connect( mStorageUrlExpression, &QLineEdit::textChanged, this, &QgsEditorConfigWidget::changed );
 
   mDocumentViewerContentComboBox->addItem( tr( "No Content" ), QgsExternalResourceWidget::NoContent );
   mDocumentViewerContentComboBox->addItem( tr( "Image" ), QgsExternalResourceWidget::Image );
@@ -135,6 +155,11 @@ QVariantMap QgsExternalResourceConfigDlg::config()
 {
   QVariantMap cfg;
 
+  cfg.insert( QStringLiteral( "StorageType" ), mStorageType->currentData() );
+  cfg.insert( QStringLiteral( "StorageAuthConfigId" ), mAuthSettingsProtocol->configId() );
+  if ( !mStorageUrl->text().isEmpty() )
+    cfg.insert( QStringLiteral( "StorageUrl" ), mStorageUrl->text() );
+
   cfg.insert( QStringLiteral( "FileWidget" ), mFileWidgetGroupBox->isChecked() );
   cfg.insert( QStringLiteral( "FileWidgetButton" ), mFileWidgetButtonGroupBox->isChecked() );
   cfg.insert( QStringLiteral( "FileWidgetFilter" ), mFileWidgetFilterLineEdit->text() );
@@ -174,6 +199,16 @@ QVariantMap QgsExternalResourceConfigDlg::config()
 
 void QgsExternalResourceConfigDlg::setConfig( const QVariantMap &config )
 {
+  if ( config.contains( QStringLiteral( "StorageType" ) ) )
+  {
+    const int index = mStorageType->findData( config.value( QStringLiteral( "StorageType" ) ) );
+    if ( index >= 0 )
+      mStorageType->setCurrentIndex( index );
+  }
+
+  mAuthSettingsProtocol->setConfigId( config.value( QStringLiteral( "StorageAuthConfigId" ) ).toString() );
+  mStorageUrl->setText( config.value( QStringLiteral( "StorageUrl" ) ).toString() );
+
   if ( config.contains( QStringLiteral( "FileWidget" ) ) )
   {
     mFileWidgetGroupBox->setChecked( config.value( QStringLiteral( "FileWidget" ) ).toBool() );
@@ -240,3 +275,23 @@ void QgsExternalResourceConfigDlg::setConfig( const QVariantMap &config )
     }
   }
 }
+
+QgsExpressionContext QgsExternalResourceConfigDlg::createExpressionContext() const
+{
+  QgsExpressionContext context = QgsEditorConfigWidget::createExpressionContext();
+  context << QgsExpressionContextUtils::formScope( );
+  context << QgsExpressionContextUtils::parentFormScope( );
+
+  QgsExpressionContextScope *fileWidgetScope = QgsFileWidget::createFileWidgetScope();
+  context << fileWidgetScope;
+
+  context.setHighlightedVariables( fileWidgetScope->variableNames() );
+  return context;
+}
+
+void QgsExternalResourceConfigDlg::changeStorageType( int storageType )
+{
+  // first one in combo box is not an external storage
+  mExternalStorageGroupBox->setVisible( storageType );
+  emit changed();
+}

src/gui/editorwidgets/qgsexternalresourceconfigdlg.h

@@ -38,6 +38,8 @@ class GUI_EXPORT QgsExternalResourceConfigDlg : public QgsEditorConfigWidget, pr
     //! Constructor for QgsExternalResourceConfigDlg
     explicit QgsExternalResourceConfigDlg( QgsVectorLayer *vl, int fieldIdx, QWidget *parent = nullptr );
 
+    QgsExpressionContext createExpressionContext() const override;
+
     // QgsEditorConfigWidget interface
   public:
     QVariantMap config() override;
@@ -49,6 +51,10 @@ class GUI_EXPORT QgsExternalResourceConfigDlg : public QgsEditorConfigWidget, pr
 
     //! Modify RelativeDefault according to mRootPath content
     void enableRelativeDefault();
+
+    //! change storage type according to index from storage type combo box
+    void changeStorageType( int index );
+
 };
 
 #endif // QGSEXTERNALRESOURCECONFIGDLG_H

src/gui/editorwidgets/qgsexternalresourcewidgetfactory.cpp

@@ -19,14 +19,15 @@
 #include "qgsexternalresourcewidgetwrapper.h"
 #include "qgsexternalresourceconfigdlg.h"
 
-QgsExternalResourceWidgetFactory::QgsExternalResourceWidgetFactory( const QString &name )
+QgsExternalResourceWidgetFactory::QgsExternalResourceWidgetFactory( const QString &name, QgsMessageBar *messageBar )
   : QgsEditorWidgetFactory( name )
+  , mMessageBar( messageBar )
 {
 }
 
 QgsEditorWidgetWrapper *QgsExternalResourceWidgetFactory::create( QgsVectorLayer *vl, int fieldIdx, QWidget *editor, QWidget *parent ) const
 {
-  return new QgsExternalResourceWidgetWrapper( vl, fieldIdx, editor, parent );
+  return new QgsExternalResourceWidgetWrapper( vl, fieldIdx, editor, mMessageBar, parent );
 }
 
 QgsEditorConfigWidget *QgsExternalResourceWidgetFactory::configWidget( QgsVectorLayer *vl, int fieldIdx, QWidget *parent ) const