Change Output name in Script - QGIS 3

Question

I exported a model as script using the properly option in QGIS 3.8.
The Script works perfectly, but the output name is changed.

Heres a print of the model:

I want that the script´s output name, from the Processing Toolbox, be the one that I designed in the  def initAlgorithm section, and not the given default name.

In the model, the output name comes as "output_name"
and in the script, the output name comes as "Reprojected".

Here's the converted Script:

from qgis.core import QgsProcessing
    from qgis.core import QgsProcessingAlgorithm
    from qgis.core import QgsProcessingMultiStepFeedback
    from qgis.core import QgsProcessingParameterVectorLayer
    from qgis.core import QgsProcessingParameterFeatureSink
    from qgis.core import QgsCoordinateReferenceSystem
    import processing

class Rename(QgsProcessingAlgorithm):

def initAlgorithm(self, config=None):
        self.addParameter(QgsProcessingParameterVectorLayer('shapeinput', 'ShapeInput', types=[QgsProcessing.TypeVector], defaultValue=None))
        self.addParameter(QgsProcessingParameterFeatureSink('Output_name', 'output_name', type=QgsProcessing.TypeVectorAnyGeometry, createByDefault=True, defaultValue=None))

def processAlgorithm(self, parameters, context, model_feedback):
        # Use a multi-step feedback, so that individual child algorithm progress reports are adjusted for the
        # overall progress through the model
        feedback = QgsProcessingMultiStepFeedback(1, model_feedback)
        results = {}
        outputs = {}

# Reproject Layer
        alg_params = {
            'INPUT': parameters['shapeinput'],
            'TARGET_CRS': QgsCoordinateReferenceSystem('EPSG:4326'),
            'OUTPUT': parameters['Output_name']
        }
        outputs['ReprojectLayer'] = processing.run('native:reprojectlayer', alg_params, context=context, feedback=feedback, is_child_algorithm=True)
        results['Output_name'] = outputs['ReprojectLayer']['OUTPUT']
        return results

def name(self):
        return 'rename'

def displayName(self):
        return 'rename'

def group(self):
        return 'rename'

def groupId(self):
        return ''

def createInstance(self):
        return Rename()

Herbert Santos · Accepted Answer

I got it!
the last step of the script must be executed inside a variable, here called step1
so it respects the name entered in the output parameter through the last block
from qgis.core import QgsProcessing
from qgis.core import QgsProcessingAlgorithm
from qgis.core import QgsProcessingMultiStepFeedback
from qgis.core import QgsProcessingParameterVectorLayer
from qgis.core import QgsProcessingParameterFeatureSink
from qgis.core import QgsFeatureSink

import processing

class Model(QgsProcessingAlgorithm):

def initAlgorithm(self, config=None):
        self.addParameter(QgsProcessingParameterVectorLayer('vetor', 'vetor', defaultValue=None))
        self.addParameter(QgsProcessingParameterFeatureSink('exit', 'exit name', type=QgsProcessing.TypeVectorPolygon, createByDefault=True, defaultValue=None))

def processAlgorithm(self, parameters, context, model_feedback):
        feedback = QgsProcessingMultiStepFeedback(1, model_feedback)
        results = {}
        outputs = {}

step1 = processing.run("native:buffer", {
                'DISSOLVE': False,
                'DISTANCE': 10,
                'END_CAP_STYLE': 0,
                'INPUT': parameters['vetor'],
                'JOIN_STYLE': 0,
                'MITER_LIMIT': 2,
                'SEGMENTS': 5,
                'OUTPUT': 'memory:'
            }, context=context, feedback=feedback)['OUTPUT']

"""here the output name is changed"""
        source = step1
        (sink, dest_id) = self.parameterAsSink(parameters,'exit',context,source.fields(),source.wkbType(),source.sourceCrs())
        features = source.getFeatures()
        for current, feature in enumerate(features):
            sink.addFeature(feature, QgsFeatureSink.FastInsert)

return results

def name(self):
        return 'rename'

def displayName(self):
        return 'rename'

def group(self):
        return ''

def groupId(self):
        return ''

def createInstance(self):
        return Model()

Jhon Galindo · Answer

If you need change the name of output, you can do it with this:

alg_params = {
        'INPUT': parameters['shapeinput'],
        'TARGET_CRS': QgsCoordinateReferenceSystem('EPSG:4326'),
        'OUTPUT': 'memory:Name_layer'
    }

or if you want to save, only do this:

path = '/home/shade/Desktop/name_layer.shp' #or something like that

alg_params = {
        'INPUT': parameters['shapeinput'],
        'TARGET_CRS': QgsCoordinateReferenceSystem('EPSG:4326'),
        'OUTPUT': path
    }

For example:

I run the next code:

layer = iface.activeLayer()

alg_params = {
    'INPUT': layer,
    'TARGET_CRS': QgsCoordinateReferenceSystem('EPSG:4326'),
    'OUTPUT': 'memory:Name_layer'
}

result = processing.run('native:reprojectlayer', alg_params)

print ('This is the result: {}'.format(result['OUTPUT']))
print ('This is the name of the layer result: {}'.format(result['OUTPUT'].name()))

And obtained this:

Change Output name in Script - QGIS 3

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