- Lab
- A Cloud Guru
Cookbook Components - Attributes
In this lab we will install the ChefDK tools on a server. We will need to make sure Docker is working, then ensure that Git is installed and has some basic configuration. Then we'll gain an understanding of Local Cookbook Development by creating a cookbook that uses a custom attribute to install a package. At the end of this hands-on lab, we will have installed and configured ChefDK tools, developed cookbooks, and tested them with `docker` and `kitchen` commands.
Path Info
Table of Contents
-
Challenge
On the Provided Server, Install Version 2.4.17 of the ChefDK Tools
We need to download the correct version of ChefDK, which is 2.4.17. In a command line, run:
wget https://packages.chef.io/files/stable/chefdk/2.4.17/el/7/chefdk-2.4.17-1.el7.x86_64.rpm
Now install it:
sudo rpm -ivh chefdk-2.4.17-1.el7.x86_64.rpm
Once it's installed, we need to make sure Chef uses the correct system locations for things:
echo 'eval "$(chef shell-init bash)"' >> ~/.bash_profile source ~/.bash_profile
Now check to see if it worked with
which ruby
, and we should see/opt/chefdk/embedded/bin/ruby
get returned. -
Challenge
Install What docker-ce Requires on This Server
We need Docker on our workstation, so we will need to install the
yum-util
s, add the Docker repository, and install Docker.sudo yum -y install yum-utils sudo yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo sudo yum -y install docker-ce
Now let's set Docker to start now, and on system boot:
sudo systemctl start docker sudo systemctl enable docker
We should also set your user to be able to use Docker without using the
sudo
command. Once we've done this, we have to log out and back in again:sudo usermod -aG docker $USER exit
Use SSH to get back in again, and check to make sure Docker is running:
docker ps
If we can do that without prefacing it with
sudo
, we're ready to continue. -
Challenge
Install Git and Set Some Global Defaults for Our User, Email Address, and Editor
When we use Kitchen, later in the lab, we need Git to be installed and set up with some basic information. These commands will make that happen:
Install it:
sudo yum -y install git
Configure some Git basics, like the username, email address, and a default text editor:
git config --global user.name "USERNAME" git config --global user.email "[email protected]" git config --global core.editor vim
Note: We can use fake email information, since we don't actually use it for this lab. It just needs to be set or we will get errors later.
-
Challenge
Install the Gem Required for Using Docker with the Test Kitchen
Docker requires a gem for this all to work. Install it with this:
gem install kitchen-docker
-
Challenge
Update SELinux to Be Permissive
To perform the tasks properly you should change SELinux so that it is permissive:
sudo setenforce permissive
We should also
/etc/selinux/config
and change things to permissive there too:sudo vim /etc/selinux/config
Change the
SELINUX
line fromSELINUX=enforcing
toSELINUX=permissive
-
Challenge
Create a Cookbook for Use with These Tasks, and Call It la_attributes
Create the cookbook with this command:
chef generate cookbook la_attributes
Now get into the newly created directory:
cd la_attributes
-
Challenge
Generate an Attribute Called default
Now we can generate an attributes, called
default
:chef generate attribute default
We'll see an
attibutes
directory, if we runls
. -
Challenge
Edit Our kitchen.yml File
We need to change some things in
kitchen.yml
, so let's edit it:vim .kitchen.yml
In the top section, we're going to replace
vagrant
withdocker
, and add some things. When we're done, that top section should look like this:--- driver: name: docker privileged: true use_sudo: false
Remember that this is YAML, so we need to make sure we have the right number of spaces in spots. Those lines under
driver
are all indented two spaces.Down in the
provisioner
section, we need to add a name and version. It should look like this when we're done:provisioner: name: chef_zero # You may wish to disable always updating cookbooks in CI or other testing environments. # For example: # always_update_cookbooks: <%= !ENV['CI'] %> always_update_cookbooks: true product_name: "chef" product_version: "13.8.5"
We're on a CentOS machine, so we need to get rid of
ubuntu
from the file. Just delete (or comment out) the line in theplatforms
section that reads:- name: ubuntu-16.04
That's it for
kitchen.yml
edits. Write and quit, so that we can get back to the command prompt. -
Challenge
Edit the Attribute We Created Earlier, and Add a default Attribute of app and language with a value of perl
Edit the
attributes/default.rb
file:vim attributes/default.rb
Add the specific attributes:
default['app']['language'] = 'perl'
-
Challenge
Edit Our Recipe to Install What Our Attribute Calls For
We need to get the
perl
package installed, the one we referred to back in the attribute, so add this text to the end of the./recipes/default.rd
file:package node['app']['language'] do action :install end
-
Challenge
Verify That the Cookbooks Work
Use the
kitchen verify
command to ensure the cookbook works. We should see a line in the output that says yum_package[perl] action install. -
Challenge
Log into the Kitchen Instance to Check That Perl Got Installed
We can log in with
kitchen login
. Once we're in, we'll runperl -v
. If we get a version number, then we know Perl has been installed. -
Challenge
Clean up the Environment
To clean up after ourselves, we just use the
kitchen destroy
command.
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