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- In this video,

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we will discover options
to change file contents.

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So how does it work?

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Well, there is ansible.builtin.copy

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by which we've talked before, which

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you can use to create
files with simple contents.

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There's also ansible.builtin.replace,

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which is used for simple replacements.

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A lineinfile can be used to

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manipulate single lines in a text file.

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And finally, there's blockinfile.

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Blockinfile is useful for

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manipulating complete blocks of texts.

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It offers a little bit more possibilities.

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Let's talk about copy and replace.

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Both of them can be used
for simple operations.

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You can use a content
argument to the copy module

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to copy your string
into a destination file.

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As in ansible all minus m copy,

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content is hello,
destination is TMP hellofile.

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So that will create a file
with the name hellofile,

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with the content hello inside the file.

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The replace module is
going a little bit further.

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It allows you to replace file contents

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based on a regular expression.

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It uses the regexp argument
to identify the regular

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expression that you want to replace.

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And, replace, itself, is where

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you specified the replacement text.

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You can also just omit
the replace argument

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if you just want to remove text.

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Completely different solutions are offered

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by lineinfile and blockinfile.

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You can use lineinfile to add
a single line to a file.

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And, also to determine where exactly

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this file is going to be created.

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And, you can use blockinfile to

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add multiple lines to a file.

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Let's go have a look at an example.

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So the example is the file copied.yml

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and you can find it in
the files directly in

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the get up repository.

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In this file, there's a
couple of modules I used.

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So to start with, there is the task copy,

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which is copying over
the source, etc hosts,

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to the destination TMP.

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If you are using copy,
then you will always copy

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from the control host to the managed host.

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So etc hosts is a file as it
exists on the control host.

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Next, this playbook is using blockinfile

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to add some lines to the TMP hosts.

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So, the path is TMP host and the block

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specified is right here.

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Notice the pipe behind
the name of the module

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which is making sure that the next couple

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of lines is written to
the configuration file

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with this specific layout.

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You can see this text is
wrapped over multiple lines.

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If you want to keep
that, you need this pipe.

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State present, ensures that
these lines will be added.

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Next, we are using this stat module.

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I haven't mentioned the stat module before

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but the stat module is a convenient module

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that helps you to verify
properties of files.

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So, we are verifying the TMP host file

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and the checksum algorithm is MD five.

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And then, the stat model is mostly used

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in combination with the register

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because otherwise you
don't see what it is doing.

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So it registers a variable
with a name result

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and then it debugs the
checksum of TMP host is a

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result.stat.checksum.

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And, finally we are using
fetch to fetch a file.

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So it fetches TMP hosts to
the destination slash TMP.

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Let's learn this playbook

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and let's figure out what it is doing.

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So let me use Ansible playbook on copy.

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And there we go.

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We can see all the work that it is doing.

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The output itself is
not revealing very much.

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We can see the result
of the debug command.

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That's an interesting one because

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that's what we've used
the debug module for.

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And then it fetches a file.

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Now the interesting
thing here is in fetch.

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Let's check out the TMP
directory because it was

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instructed to fetch to the TMP directory.

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There, you can see in the
TMP directory, there's

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an ansible1 as well as
an ansible2 sub directory.

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And in this ansible1
directory, what do we find?

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Well, let's check it out.

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Ansible1, where we can
find a TMP sub directory.

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That is what fetch is doing.

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Fetch is maintaining the entire patent

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as it exists on the target host,

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and you will find the target host name

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in the path on the control host as well.

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And that is to allow you optimal control

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to the different files that are fetched

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from different hosts, because otherwise

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how would Ansible ever see the difference

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between the different hosts?

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In the next video we
are going to talk about find.

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And I have a nice example of advanced file

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manipulations in that video as well.