# Shell Tasks
prefect.tasks.shell.ShellTask(command=None, env=None, helper_script=None, shell="bash", return_all=False, log_stderr=False, stream_output=False, **kwargs)[source]
Task for running arbitrary shell commands.
NOTE: This task combines stderr and stdout because reading from both streams without blocking is tricky.
command (string, optional): shell command to be executed; can also be provided post-initialization by calling this task instance
env (dict, optional): dictionary of environment variables to use for the subprocess; can also be provided at runtime
helper_script (str, optional): a string representing a shell script, which will be executed prior to the
commandin the same process. Can be used to change directories, define helper functions, etc. when re-using this Task for different commands in a Flow; can also be provided at runtime
shell (string, optional): shell to run the command with; defaults to "bash"
return_all (bool, optional): boolean specifying whether this task should return all lines of stdout as a list, or just the last line as a string; defaults to
log_stderr (bool, optional): boolean specifying whether this task should log the output in the case of a non-zero exit code; defaults to
False. This actually logs both stderr and stdout and will only log the last line of output unless
stream_output (Union[bool, int, str], optional): specifies whether this task should log the output as it occurs, and at what logging level. If
Trueis passed, the logging level defaults to
INFO; otherwise, any integer or string value that's passed will be treated as the log level, provided the
logginglibrary can successfully interpret it. If enabled,
log_stderrwill be ignored as the output will have already been logged. defaults to
**kwargs: additional keyword arguments to pass to the Task constructor
stream_outputis passed in as a string, but cannot successfully be converted to a numeric value by logging.getLevelName()
from prefect import Flow from prefect.tasks.shell import ShellTask task = ShellTask(helper_script="cd ~") with Flow("My Flow") as f: # both tasks will be executed in home directory contents = task(command='ls') mv_file = task(command='mv .vimrc /.vimrc') out = f.run()
prefect.tasks.shell.ShellTask.run(command=None, env=None, helper_script=None)[source]
Run the shell command.
This documentation was auto-generated from commit 59ae220
on April 9, 2021 at 15:46 UTC