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- In this video, I want to
tell you about Register.

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Register is a nice way
to automatically define

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your variables based on command result.

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So the thing of Register
is that you can use it

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to store the result of
a task, in a variable.

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It provides a very nice way
to perform specific tasks

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only upon success or
failure of another task.

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That means that it'll become really useful

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once we have talked about conditionals.

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But, as Register is about
a way to create variables,

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I'd like to have a look
at a quick example.

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So here is register.yaml
and what do we have?

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Well, a very simple playbook.

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In this playbook we are using

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the shell command to run a command.

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Notice that there's no real
reason to use shell here,

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could have used command as well.

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What it's all about, is register.

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Register stores the
result of the shell module

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in a variable with an passwd_contents

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And next in debug, we are going to check

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this passwd_contents value.

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So ansible-playbook on register.yaml

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is doing this, it's gathering the facts.

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And there we go. Here we have
the result of the register.

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So register defines its
variable on every single host.

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So basically, it becomes
a property of the host.

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And in this host, we
can see that it contains

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detailed information about the success

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or failure of the exam.

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So we can see whether or not it changed.

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We can see it's, whether
or not it's failed.

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We can see rc for the return code,

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which is the result of the command.

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We can see when it started.

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The stdout put, the stdout put in lines.

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And a nice thing is, you
can address all of them

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like passwd_contents.rc is
going to print the return code.

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You know what? Let's tweak
this playbook a little bit.

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Now let me show you debug, msg,

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the status of the command
is {{ passwd_contents.rc }}

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Notice, by the way, that
there's no real reason

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why double quotes I used here.

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You might as well omit
them, then it'll also work.

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So there we go, the status
of the command is zero.

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Note by the way, that I'm
using passwd_contents.rc

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and in case you are
thinking, "Hey, (indistinct),

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"is that the right way of doing it?"

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Then I would say, "Good point!"

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This is how you should be doing it.

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Square bracket, single quote notation.

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But the doted notation is so common

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that you will find it
still, every now and then.