Python Fabric : tricky ssh issue

Question

I have a system that i use to run a fabric script that executes test cases on several other client systems.(via launch_process.sh)

@task
@hosts('controller')
def run_script():
           run('/test/launch_process.sh')
           #below line didn't work 
           check_ps()


@task
@hosts('clients')
def check_ps():
           run('ps aux | grep myprocess')

when we do fab run_script

it launches the process on other machines (assume machine2,machine3) Now I would like to use 'ps' command to confirm ,the process running or not. But check_ps() runs on 'controller' itself - not on clients.

Any thoughts on how to achieve this ?

(looking for solution ,without using passwdless login and popen or paramiko)

Have a look here for your answer: http://stackoverflow.com/questions/5346135/can-a-python-fabric-task-invoke-other-tasks-and-respect-their-hosts-lists — dhwthompson, Mar 14 '12 at 11:57

score 2 · Accepted Answer · answered Mar 14 '12 at 18:37

Fabric has execute() now. http://docs.fabfile.org/en/1.4.0/api/core/tasks.html#fabric.tasks.execute

That'll let you do:

@task
@hosts('controller')
def run_script():
    run('/test/launch_process.sh')
    execute(check_ps, hosts=['client'])

And with that the @hosts on check_ps is still valid in the event you want to run it alone (w/o run_script())

Python Fabric : tricky ssh issue

1 Answers1