Update QgsProcessingModelChildAlgorithm::asPythonCode for 3.x API

python/core/auto_generated/processing/models/qgsprocessingmodelchildalgorithm.sip.in

@@ -298,9 +298,15 @@ Loads this child from a QVariant.
 .. seealso:: :py:func:`toVariant`
 %End
 
-    QString asPythonCode() const;
+    QStringList asPythonCode( QgsProcessing::PythonOutputType outputType, const QgsStringMap &extraParameters, int currentIndent, int indentSize ) const;
 %Docstring
-Attempts to convert the child to executable Python code.
+Attempts to convert the child to executable Python code, and returns a list of the generated lines of code.
+
+The ``outputType`` argument specifies the type of script to generate.
+
+Additional parameters to be passed to the child algorithm are specified in the ``extraParameters`` argument.
+
+The ``currentIndent`` and ``indentSize`` are used to set the base line indent and size of further indented lines respectively.
 %End
 
 };

src/core/processing/models/qgsprocessingmodelchildalgorithm.cpp

@@ -162,39 +162,53 @@ bool QgsProcessingModelChildAlgorithm::loadVariant( const QVariant &child )
   return true;
 }
 
-QString QgsProcessingModelChildAlgorithm::asPythonCode() const
+QStringList QgsProcessingModelChildAlgorithm::asPythonCode( const QgsProcessing::PythonOutputType outputType, const QgsStringMap &extraParameters, int currentIndent, int indentSize ) const
 {
   QStringList lines;
+  const QString baseIndent = QString( ' ' ).repeated( currentIndent );
+  const QString lineIndent = QString( ' ' ).repeated( indentSize );
 
   if ( !algorithm() )
-    return QString();
+    return QStringList();
 
   QStringList paramParts;
-  QMap< QString, QgsProcessingModelChildParameterSources >::const_iterator paramIt = mParams.constBegin();
+  for ( auto paramIt = mParams.constBegin(); paramIt != mParams.constEnd(); ++paramIt )
-  for ( ; paramIt != mParams.constEnd(); ++paramIt )
   {
     QStringList sourceParts;
-    Q_FOREACH ( const QgsProcessingModelChildParameterSource &source, paramIt.value() )
+    const QgsProcessingParameterDefinition *def = algorithm() ? algorithm()->parameterDefinition( paramIt.key() ) : nullptr;
+    const auto parts = paramIt.value();
+    for ( const QgsProcessingModelChildParameterSource &source : parts )
     {
-      QString part = source.asPythonCode();
+      QString part = source.asPythonCode( outputType, def );
       if ( !part.isEmpty() )
-        sourceParts << QStringLiteral( "'%1':%2" ).arg( paramIt.key(), part );
+        sourceParts << part;
     }
     if ( sourceParts.count() == 1 )
-      paramParts << sourceParts.at( 0 );
+      paramParts << QStringLiteral( "'%1':%2" ).arg( paramIt.key(), sourceParts.at( 0 ) );
     else
-      paramParts << QStringLiteral( "[%1]" ).arg( paramParts.join( ',' ) );
+      paramParts << QStringLiteral( "'%1':[%2]" ).arg( paramIt.key(), sourceParts.join( ',' ) );
   }
 
-  lines << QStringLiteral( "outputs['%1']=processing.run('%2', {%3}, context=context, feedback=feedback)" ).arg( mId, mAlgorithmId, paramParts.join( ',' ) );
+  lines << baseIndent + QStringLiteral( "alg_params = {" );
-
+  lines.reserve( lines.size() + paramParts.size() );
-  QMap< QString, QgsProcessingModelOutput >::const_iterator outputIt = mModelOutputs.constBegin();
+  for ( const QString &p : qgis::as_const( paramParts ) )
-  for ( ; outputIt != mModelOutputs.constEnd(); ++outputIt )
   {
-    lines << QStringLiteral( "results['%1']=outputs['%2']['%3']" ).arg( outputIt.key(), mId, outputIt.value().childOutputName() );
+    lines << baseIndent + lineIndent + p + ',';
+  }
+  for ( auto it = extraParameters.constBegin(); it != extraParameters.constEnd(); ++it )
+  {
+    lines << baseIndent + lineIndent + QgsProcessingUtils::stringToPythonLiteral( it.key() ) + ':' + it.value() + ',';
+  }
+  lines << baseIndent + QStringLiteral( "}" );
+
+  lines << baseIndent + QStringLiteral( "outputs['%1']=processing.run('%2', alg_params, context=context, feedback=feedback, is_child_algorithm=True)" ).arg( mId, mAlgorithmId );
+
+  for ( auto outputIt = mModelOutputs.constBegin(); outputIt != mModelOutputs.constEnd(); ++outputIt )
+  {
+    lines << baseIndent + QStringLiteral( "results['%1:%2']=outputs['%1']['%3']" ).arg( mId, outputIt.key(), outputIt.value().childOutputName() );
   }
 
-  return lines.join( '\n' );
+  return lines;
 }
 
 QVariantMap QgsProcessingModelChildAlgorithm::configuration() const

src/core/processing/models/qgsprocessingmodelchildalgorithm.h

@@ -278,9 +278,15 @@ class CORE_EXPORT QgsProcessingModelChildAlgorithm : public QgsProcessingModelCo
     bool loadVariant( const QVariant &child );
 
     /**
-     * Attempts to convert the child to executable Python code.
+     * Attempts to convert the child to executable Python code, and returns a list of the generated lines of code.
+     *
+     * The \a outputType argument specifies the type of script to generate.
+     *
+     * Additional parameters to be passed to the child algorithm are specified in the \a extraParameters argument.
+     *
+     * The \a currentIndent and \a indentSize are used to set the base line indent and size of further indented lines respectively.
      */
-    QString asPythonCode() const;
+    QStringList asPythonCode( QgsProcessing::PythonOutputType outputType, const QgsStringMap &extraParameters, int currentIndent, int indentSize ) const;
 
   private:
 

tests/src/analysis/testqgsprocessing.cpp

@@ -6152,6 +6152,11 @@ void TestQgsProcessing::modelerAlgorithm()
   QVERIFY( child.setAlgorithmId( QStringLiteral( "native:centroids" ) ) );
   QVERIFY( child.algorithm() );
   QCOMPARE( child.algorithm()->id(), QStringLiteral( "native:centroids" ) );
+  QCOMPARE( child.asPythonCode( QgsProcessing::PythonQgsProcessingAlgorithmSubclass, QgsStringMap(), 4, 2 ).join( '\n' ), QStringLiteral( "    alg_params = {\n    }\n    outputs['']=processing.run('native:centroids', alg_params, context=context, feedback=feedback, is_child_algorithm=True)" ) );
+  QgsStringMap extraParams;
+  extraParams[QStringLiteral( "SOMETHING" )] = QStringLiteral( "SOMETHING_ELSE" );
+  extraParams[QStringLiteral( "SOMETHING2" )] = QStringLiteral( "SOMETHING_ELSE2" );
+  QCOMPARE( child.asPythonCode( QgsProcessing::PythonQgsProcessingAlgorithmSubclass, extraParams, 4, 2 ).join( '\n' ), QStringLiteral( "    alg_params = {\n      'SOMETHING':SOMETHING_ELSE,\n      'SOMETHING2':SOMETHING_ELSE2,\n    }\n    outputs['']=processing.run('native:centroids', alg_params, context=context, feedback=feedback, is_child_algorithm=True)" ) );
   // bit of a hack -- but try to simulate an algorithm not originally available!
   child.mAlgorithm.reset();
   QVERIFY( !child.algorithm() );
@@ -6194,6 +6199,8 @@ void TestQgsProcessing::modelerAlgorithm()
   QCOMPARE( child.parameterSources().value( QStringLiteral( "b" ) ).at( 0 ).staticValue().toInt(), 7 );
   QCOMPARE( child.parameterSources().value( QStringLiteral( "b" ) ).at( 1 ).staticValue().toInt(), 9 );
 
+  QCOMPARE( child.asPythonCode( QgsProcessing::PythonQgsProcessingAlgorithmSubclass, extraParams, 4, 2 ).join( '\n' ), QStringLiteral( "    alg_params = {\n      'a':5,\n      'b':[7,9],\n      'SOMETHING':SOMETHING_ELSE,\n      'SOMETHING2':SOMETHING_ELSE2,\n    }\n    outputs['my_id']=processing.run('native:centroids', alg_params, context=context, feedback=feedback, is_child_algorithm=True)" ) );
+
   QgsProcessingModelOutput testModelOut;
   testModelOut.setChildId( QStringLiteral( "my_id" ) );
   QCOMPARE( testModelOut.childId(), QStringLiteral( "my_id" ) );
@@ -6228,6 +6235,8 @@ void TestQgsProcessing::modelerAlgorithm()
   QCOMPARE( child.modelOutput( "a" ).description(), QStringLiteral( "my output" ) );
   child.modelOutput( "a" ).setDescription( QStringLiteral( "my output 2" ) );
   QCOMPARE( child.modelOutput( "a" ).description(), QStringLiteral( "my output 2" ) );
+  QCOMPARE( child.asPythonCode( QgsProcessing::PythonQgsProcessingAlgorithmSubclass, extraParams, 4, 2 ).join( '\n' ), QStringLiteral( "    alg_params = {\n      'a':5,\n      'b':[7,9],\n      'SOMETHING':SOMETHING_ELSE,\n      'SOMETHING2':SOMETHING_ELSE2,\n    }\n    outputs['my_id']=processing.run('native:centroids', alg_params, context=context, feedback=feedback, is_child_algorithm=True)\n    results['my_id:a']=outputs['my_id']['']" ) );
+
   // no existent
   child.modelOutput( "b" ).setDescription( QStringLiteral( "my output 3" ) );
   QCOMPARE( child.modelOutput( "b" ).description(), QStringLiteral( "my output 3" ) );