调用 BashOperator 时出错：Bash 命令失败

这是我的 dag 文件和 BashOperator 任务：

my_dag = { 
dag_id = 'my_dag',
start_date = datetime(year=2017, month=3, day=28),
schedule_interval='01***',
}

my_bash_task = BashOperator(
task_id="my_bash_task",
bash_command=bash_command,
dag=my_dag)

bash_command = "/home/jak/my_projects/workflow_env/repo_workflow/db_backup_bash.sh ""

按照此answer https://stackoverflow.com/questions/42259298/bashoperator-doent-run-bash-file-apache-airflow我什至在 bash 文件后面留了一个空格以避免找不到模板错误。但是在运行这个任务时给了我这个错误：airflow.exceptions.AirflowException：Bash 命令失败.

bash_command 文件内容为：

#!/bin/bash
DATABASE=db_name
FILE=$DATABASE-`date +%F-%H%M%S`.backup
export PGPASSWORD=password
pg_dump -h localhost -p 5432 -U developer -F c -b -v -f ~/Dropbox/database_backup/location/$FILE db_name
unset PGPASSWORD

但是，不要将 bash_command 指向 bash 文件，而是以多行字符串形式编写命令：

bash_command = """
DATABASE=db_name
FILE=$DATABASE-`date +%F-%H%M%S`.backup
export PGPASSWORD=password
pg_dump -h localhost -p 5432 -U developer -F c -b -v -f ~/Dropbox/database_backup/location/$FILE db_name
unset PGPASSWORD
"""

因此，我假设该错误不是因为 bash 命令造成的。 我什至尝试用 #!/bin/sh 替换 bash 文件中的 #!/bin/bash，但这也不起作用。

I ran sh db_back_up_bash.sh来自终结者，它工作正常。

Update The 实际代码：

bash_file_location_to_backup_db = '{{"/home/jak/my_projects/workflow_env/repo_workflow/db_backup_bash.sh"}}'
# bash_file_location_to_backup_db = "/home/jak/my_projects/workflow_env/repo_workflow/db_backup_bash.sh "
bash_command = """
DATABASE=ksaprice_scraping
FILE=$DATABASE-`date +%F-%H%M%S`.backup
export PGPASSWORD=password
pg_dump -h localhost -p 5432 -U developer -F c -b -v -f ~/Dropbox/database_backup/ksaprice/$FILE ksaprice_scraping
unset PGPASSWORD
"""

backup_scraped_db_in_dropbox_task = BashOperator(
    task_id="backup_scraped_db_in_dropbox_task",
    # bash_command=bash_command,# this works fine
    bash_command=bash_file_location_to_backup_db,#this give error :airflow.exceptions.AirflowException: Bash command failed
    dag=dag_crawl
)

错误跟踪：

[2017-04-11 20:02:14,905] {bash_operator.py:90} INFO - Output:
2017-04-11 20:02:14,905 | INFO| root : Output:
[2017-04-11 20:02:14,906] {bash_operator.py:94} INFO - /tmp/airflowtmp7FffJ2/backup_scraped_db_in_dropbox_taskQ6IVxm: line 1: /home/jak/my_projects/workflow_env/repo_workflow/db_backup_bash.sh: Permission denied
2017-04-11 20:02:14,906 | INFO| root : /tmp/airflowtmp7FffJ2/backup_scraped_db_in_dropbox_taskQ6IVxm: line 1: /home/jak/my_projects/workflow_env/repo_workflow/db_backup_bash.sh: Permission denied
[2017-04-11 20:02:14,906] {bash_operator.py:97} INFO - Command exited with return code 126
2017-04-11 20:02:14,906 | INFO| root : Command exited with return code 126
[2017-04-11 20:02:14,906] {models.py:1417} ERROR - Bash command failed
Traceback (most recent call last):
  File "/home/jak/my_projects/workflow_env/local/lib/python2.7/site-packages/airflow/models.py", line 1374, in run
    result = task_copy.execute(context=context)
  File "/home/jak/my_projects/workflow_env/local/lib/python2.7/site-packages/airflow/operators/bash_operator.py", line 100, in execute
    raise AirflowException("Bash command failed")
AirflowException: Bash command failed
2017-04-11 20:02:14,906 | ERROR| root : Bash command failed
Traceback (most recent call last):
  File "/home/jak/my_projects/workflow_env/local/lib/python2.7/site-packages/airflow/models.py", line 1374, in run
    result = task_copy.execute(context=context)
  File "/home/jak/my_projects/workflow_env/local/lib/python2.7/site-packages/airflow/operators/bash_operator.py", line 100, in execute
    raise AirflowException("Bash command failed")
AirflowException: Bash command failed
[2017-04-11 20:02:14,907] {models.py:1441} INFO - Marking task as FAILED.
2017-04-11 20:02:14,907 | INFO| root : Marking task as FAILED.
[2017-04-11 20:02:14,947] {models.py:1462} ERROR - Bash command failed
2017-04-11 20:02:14,947 | ERROR| root : Bash command failed
Traceback (most recent call last):
  File "/home/jak/my_projects/workflow_env/bin/airflow", line 28, in <module>
    args.func(args)
  File "/home/jak/my_projects/workflow_env/local/lib/python2.7/site-packages/airflow/bin/cli.py", line 585, in test
    ti.run(ignore_task_deps=True, ignore_ti_state=True, test_mode=True)
  File "/home/jak/my_projects/workflow_env/local/lib/python2.7/site-packages/airflow/utils/db.py", line 53, in wrapper
    result = func(*args, **kwargs)
  File "/home/jak/my_projects/workflow_env/local/lib/python2.7/site-packages/airflow/models.py", line 1374, in run
    result = task_copy.execute(context=context)
  File "/home/jak/my_projects/workflow_env/local/lib/python2.7/site-packages/airflow/operators/bash_operator.py", line 100, in execute
    raise AirflowException("Bash command failed")
airflow.exceptions.AirflowException: Bash command faile

我认为这是气流中的一个错误，jinja 不应该期望 .sh 文件包含 BashOperator 中的模板信息。

我通过将命令转换成 Jinja 能够正确解释的格式来解决这个问题：

bash_command = '{{"/home/jak/my_projects/workflow_env/repo_workflow/db_backup_bash.sh"}}'