Google Cloud Dataflow Custom Template – only in streaming pipelines

You were almost there. Just add --streaming to your command.

python -m PrintTemplate.py 
    --runner DataflowRunner --project [PROJECT] 
    --staging_location gs://[BUCKET]/staging 
    --temp_location gs://[BUCKET]/temp 
    --template_location gs://[BUCKET]/templates/PrintTemplate
    --streaming

I see that you’re using PipelineOptions. You could also pass streaming=True.

pipeline_options = PipelineOptions(
    runner='DataflowRunner',
    project=PROJECT,
    job_name='printtemplate01',
    temp_location='gs://{}/temp'.format(BUCKET),
    region='us-central1',
    streaming=True
)