task

Often you may want to execute a number of commands in parallel. This project shows an example on how to do this easily with Celery.

Our example creates a task that executes a shell command remotely on a machine. However, this is just an example you can realy create other tasks as you please.

One of the issues is how to easily stage such tasks with a number of given parameters. To make the passing uniform, we pass all arguments via kwargs.

In our example we simply devined a function such as::

@app.task
def cm_ssh(host, username, command):
    result = ssh("{0}@{1}".format(username, host), command)
    return str(result)
``

In our main program we can than call it with our Sequential or
parallel constructs such as 


from cloudmesh_task.parallel import Parallel, Sequential::

hosts = [“server1.futuregrid.org”, “server2.futuregrid.org”, “server3.futuregrid.org”, “server4.futuregrid.org”]

result = Sequential(hosts, cm_ssh, username=“gvonlasz”, command=“qstat”)

result = Parallel(hosts, cm_ssh, username=“gvonlasz”, command=“qstat”)

The first command executes the task sequentially over the array given
in the first parameter. The second one executes it in parallel


First start in one terminal the celery server::

cm-task.py start

In a second version start the test program::

python prg.py ```