When I run this
from fabric.api import env, run, local, cd
env.hosts = ['myhost']
No hosts found. Please specify (single) host string for connection:
@Chris, the reason you're seeing this behavior is because the host list is constructed before the task function is called. So, even though you're changing
env.hosts inside the function, it is too late for it to have any effect.
Whereas the command
fab setenv:foo mycmd:bar, would have resulted in something you would have expected:
$ fab setenv:foo mycmd:bar [myhost] Executing task 'mycmd' ['myhost'] [myhost] run: ls
This is the same as the accepted answer, but because of the way
setenv is defined, an argument is needed.
from fabric.api import env, run, local, cd env.hosts = ['other_host'] def setenv(foo): env.hosts = ['myhost'] def mycmd(foo): setenv(foo) print('env.hosts inside mycmd: %s' % env.hosts) run('ls')
The output of this is:
$ fab mycmd:bar [other_host] Executing task 'mycmd' env.hosts inside mycmd: ['myhost'] [other_host] run: ls Fatal error: Name lookup failed for other_host Underlying exception: (8, 'nodename nor servname provided, or not known') Aborting.
As you can see, the host-list is already set to
['other_host', ] when fabric starts to execute