30 lines
1.4 KiB
YAML
30 lines
1.4 KiB
YAML
# here's a cool advanced topic about how to perform conditional logic in ansible without resorting
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# to writing your own module that defines facts. You can do that too, and it's easy to do, but
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# often you just want to run a command and then decide whether to run some steps or not. That's
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# easy to do, and here we'll show you how.
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- name: test playbook
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user: root
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hosts: all
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tasks:
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# it is possible to save the result of any command in a named register. This variable will be made
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# available to tasks and templates made further down in the execution flow. Here we save the result
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# of a simple 'cat' command in a variable called 'motd_contents'
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- action: shell cat /etc/motd
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register: motd_contents
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# and here we access the register. Note that motd_contents as a variable is structured data because
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# it is a return from the command module. The shell module makes available variables such as
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# as 'stdout', 'stderr', and 'rc'. Here's a rather trivial example that runs an arbitrary step
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# if and only if the motd file contained the word 'hi'. Remember that only_if statements are
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# Python expressions. This is as complicated as Ansible syntax is going to get, and the only
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# time python really seeps into ansible's language.
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- action: shell echo "motd contains the word hi"
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only_if: "'${motd_contents.stdout}'.find('hi') != -1"
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