How to access or save output image after running CLI from Python

I have created or run a CLI from Python to calculate T1 mapping as follows.

cliNode = slicer.cli.runSync(slicer.modules.t1mapping, None, parameters)

Detailed script:

def t1mapping(parameters = {}):
    '''Code for running the pkmoddeling module with input parameters 
    specified in the dict'''
    # adding an alias to the module
    t1mapping = slicer.modules.t1mapping
    # creating a CLI node
    cliNode = slicer.cli.runSync(slicer.modules.t1mapping, None, parameters)
    if cliNode.GetStatus() & cliNode.ErrorsMask:
        # error
        errorText = cliNode.GetErrorText()
        raise ValueError("CLI execution failed: " + errorText)
    return cliNode

def getIputVolume(inputdir,outputdir):
    for index,DicomFolder in enumerate(DicomFolders):
        fullPath = os.path.join(inputdir,DicomFolder)
        fileNames = os.listdir(fullPath)
        for index,fileName in enumerate(fileNames):
    db = slicer.dicomDatabase
    plugin = slicer.modules.dicomPlugins['MultiVolumeImporterPlugin']()
    if plugin:
        loadables = plugin.examine([fileNames])
    if len(loadables) == 0:
        print('plugin failed to interpret this series')
        patientID = db.fileValue(loadables[0].files[0],'0010,0020')
        outputPath = os.path.join(outputdir, patientID +  ".nrrd") 
        print (outputPath)
        volume = plugin.load(loadables[0])
        slicer.util.saveNode(volume,outputPath) # saves the loaded image
    return  volume,  os.path.join(outputdir, patientID + "_T1map.nrrd") 

# get input volume and output path
inputImageVolume, outputFileName= getIputVolume(inputdir,outputdir)

# Parameters share for all patients in loop
defaultParameters = {'modelName': 'VFA'} 

# list containing parameterdict for each run of the code.
parameters = copy.copy(defaultParameters)
parameters['imageName'] = inputImageVolume 
parameters['T1MapFileName'] = outputFileName

# do actual stuff here  
t1mapping(parameters = parameters)

All parameters were set correctly and it runs without error (form cliNode.GetErrorText()). My question is how to access or save the calculated or resulting image from cliNode . I would prefer to it save as .nrrd or .mhd file.

I specified the full path in the parameters dict: e.g. parameters[‘T1MapFileName’] = ‘some_path.nrrd’.
But there is no output file or image.


parameters['imageName'] and parameters['T1MapFileName'] must be set to a valid MRML volume node object or MRML node ID. You need to create a new volume node for storing the output. See example here.

Once the CLI execution is completed, you can save the volume node to file using saveNode function. See example here.

Thanks for the guidance

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