将参数传递给 Airflow 中的依赖任务的方法是什么?我有很多 bashes 文件,我正在尝试将这种方法迁移到气流,但我不知道如何在任务之间传递一些属性。
这是一个真实的例子:
#sqoop bash template
sqoop_template = """
sqoop job --exec {{params.job}} -- --target-dir {{params.dir}} --outdir /src/
"""
s3_template = """
s3-dist-cp --src= {{params.dir}} --dest={{params.s3}}
"""
#Task of extraction in EMR
t1 = BashOperator(
task_id='extract_account',
bash_command=sqoop_template,
params={'job': 'job', 'dir': 'hdfs:///account/' + time.now().strftime("%Y-%m-%d-%H-%M-%S")},
dag=dag)
#Task to upload in s3 backup.
t2 = BashOperator(
task_id='s3_upload',
bash_command=s3_template,
params={}, #here i need the dir name created in t1
depends_on_past=True
)
t2.set_upstream(t1)
在 t2 中,我需要访问在 t1 中创建的目录名称。
解决方案
#Execute a valid job sqoop
def sqoop_import(table_name, job_name):
s3, hdfs = dirpath(table_name)
sqoop_job = job_default_config(job_name, hdfs)
#call(sqoop_job)
return {'hdfs_dir': hdfs, 's3_dir': s3}
def s3_upload(**context):
hdfs = context['task_instance'].xcom_pull(task_ids='sqoop_import')['hdfs_dir']
s3 = context['task_instance'].xcom_pull(task_ids='sqoop_import')['s3_dir']
s3_cpdist_job = ["s3-dist-cp", "--src=%s" % (hdfs), "--dest=%s" % (s3)]
#call(s3_cpdist_job)
return {'s3_dir': s3} #context['task_instance'].xcom_pull(task_ids='sqoop_import')
def sns_notify(**context):
s3 = context['task_instance'].xcom_pull(task_ids='distcp_s3')['s3_dir']
client = boto3.client('sns')
arn = 'arn:aws:sns:us-east-1:744617668409:pipeline-notification-stg'
response = client.publish(TargetArn=arn, Message=s3)
return response
这不是最终的解决方案,因此欢迎改进。谢谢。