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So friends, now that we know how to create archives,

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as well as how we can unarchive our files,

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let's add some more attention to how we can handle errors

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in our Ansible Playbooks.

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So you may notice that when you happen

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to create a particular task in Ansible

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and you encounter an error,

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what effectively happens is the playbook just crashes.

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So what this actually means is that

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if you happen to have a whole bunch of tasks,

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let's maybe say task one and task two

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and perhaps even task three,

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let's suppose we happen to have an error

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in task one, maybe you try to copy a file to a destination
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in task one, maybe you try to copy a file to a destination

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and that file doesn't even exist.

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So the module fails and effectively the playbook crashes.

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What this effectively means is that these two tasks,

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even though they can be correctly configured,

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well, they're not even going to get the chance

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to be configured because basically Ansible

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is going to work any sequential manner.

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And as soon as we encounter this error here,

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the playbook is just going to stop.

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So what we want to be able to do is to learn

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how we can handle our errors.

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So that if we happen to encounter an error,

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let's maybe say again on task one,
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let's maybe say again on task one,

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the playbook acknowledges that error

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and it handles it appropriately

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and then continues on, meaning that task two and task three,

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if they are correctly configured,

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they can still actually execute.

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Now, just as a quick note,

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if you happen to have experience

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with the Python programming language,

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not that you have to note to use Ansible,

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but many people who are using Ansible

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do have familiarity.

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What we're going to talk about here is quite similar

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to what is known as a try and accept block.

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Now, for those of you that do not have any experience,

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with Python, let me talk to you about
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with Python, let me talk to you about

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what we're actually talking about here.

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In the case of Python,

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when you want to try a piece of code

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and hope that it works,

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you can effectively use the try keyword

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and any code within this statement

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is going to be attempted to be ran.

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However, if you happen to encounter an error,

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you can create what is known as an accept block

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and then specify what you want to happen

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if the try block happens to fail.

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So whilst in Python,

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you would use the try keyword in Ansible,

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we actually specify the block keyword

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and with respect to the accept block
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and with respect to the accept block

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that you would specify in Python,

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what you actually say in Ansible as the keyword rescue.

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So those of you with Python experience

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probably now understand these concepts already,

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but for those of you that don't,

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let's dive into an example and see how it actually operates.

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So let's go on and create a playbook called play3.yml.

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So we're going to insert more TAVR3 hyphens at the top,

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give it a name,

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and we just say play3 handling errors

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and try to spell that correctly, John.

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There we go.

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So let's now target the host.
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So let's now target the host.

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Let's just go with the blue box once again.

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We'll set gather facts to be false.

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And now let's define our tasks.

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So the first task here,

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let's imagine we want to copy a particular file here.

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So we'll use the Ansible built-in copy module

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and I will specify as the source is going to be,

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so let's go into my home Ansible directory

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and let's just specify a file called random.txt.

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And then specify we want to copy it

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into the nugget user directory

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and the file can also be called random.txt.

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Now the problem is going to be here

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that on my control mode,
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that on my control mode,

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this file here does not actually exist.

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Let me show you that, okay?

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So we can see the directory I'm into an LS.

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Notice we actually don't see this random.txt file.

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So we're going to encounter an error.

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So let's continue on and have more tasks.

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Let's just call this do something else.

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Now this can be absolutely anything.

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This could be perhaps copying more files.

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It could be creating new directories.

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It could be compressing files, all that stuff.

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It doesn't actually matter.

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In the case here, just for the example,

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let me just print out a simple message, okay?

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So I'll use the Ansible built-in debug module

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and the message is going to be,
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and the message is going to be,

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this is the second task, okay?

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Super, super simple.

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Now as it transpires right now, like I say,

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because we're going to have a failure

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and this particular task here,

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the playbook is going to crash

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and therefore this task here will not actually execute.

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So let's just save this

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and I'll just say Ansible,

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play book, play three dot YML and to enter

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and look at this right here.

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We just get an exception, pretty much an error,

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specifying that we could not actually find or access
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specifying that we could not actually find or access

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this particular text file on the Ansible controller.

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So this is the error.

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Notice though, crucially, where is the second task?

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It didn't actually execute.

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We don't get to see that printed message.

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So here's what we can do.

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I think we'll go back into the actual playbook here.

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So let's go in and say play three dot YML.

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What I'm going to do here is I'm going to create a block

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and I'm going to effectively indent everything

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so let me just give this a new name.

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So let's say attempt to copy the file

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and let me just fix my indentation.

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So let's move this in for spaces and again,

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for spaces again.
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for spaces again.

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And let's maybe just change this name to do multiple tasks

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to be a little bit more descriptive.

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Now at the same level of indentation as our block,

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we want to use the rescue keyboard.

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So I'll say rescue and now I'll give this a name

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and I'll just say handle the error.

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Now again, the way you handle this is entirely up to you.

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You can perhaps maybe create a log file of the error.

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In the case here,

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what is used the answer will build in debug module

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to simply print out a message.

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What is that message going to be?

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Just say the copy task failed.

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Now with respect to the next task,

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effectively our simulation task that is not really doing much.
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effectively our simulation task that is not really doing much.

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I want this to always execute regardless, okay?

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So at the same level of indentation

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as the block and rescue keywords,

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let me have the always keyword

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and now just indent everything within once again.

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So again, for spaces, indent it.

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Perfect.

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So now we have this new playbook.

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So whilst this file here does not exist,

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we're going to encounter an error,

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as opposed to crashing,

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we'll specify that we want to print this particular message

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and then we will continue on with the other tasks

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that you want to execute.

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So let's go for this here.

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I'll say answer will playbook, play through.yml
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I'll say answer will playbook, play through.yml

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and to answer, look at this right here.

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We actually get an error message as we saw before,

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but this time we continue on,

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we specify that hey, the copy task happened to fail

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and now the next task here is going to execute.

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Now again, the example is a little bit frivolous here,

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but you can imagine this could be any particular task

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no matter how advanced.