以下代码:
def get_pipeline(workers):
pipeline_options = PipelineOptions(['--direct_num_workers', str(workers)])
return beam.Pipeline(options=pipeline_options,
runner=fn_api_runner.FnApiRunner(
default_environment=beam_runner_api_pb2.Environment(
urn=python_urns.SUBPROCESS_SDK,
payload=b'%s -m apache_beam.runners.worker.sdk_worker_main'
% sys.executable.encode('ascii'))))
with get_pipeline(4) as pipeline:
_ = (
pipeline
| 'ReadTestData' >> beam.io.ReadFromParquet(input_files, columns=all_columns)
| "write" >> beam.io.WriteToText("/tmp/txt2")
)
仅使用 4 个可用工作程序中的一个,并且仅生成一个大输出文件(即使有许多输入文件)。
如何强制 Beam 管道并行工作,即如何强制每个输入文件由不同的工作人员单独处理?