DevOps Engineering part 5. – Create an enterprise cookbook

In this exercise we will create a Chef cookbook for a corporation. It will be robust and include all the necessary elements to be used in a large enterprise. If your company already has established standards, as you progress with this tutorial, copy the appropriate file from an existing cookbook. If this is the first cookbook in your organization, or you don’t want to follow the current standards, copy the sample files from this page.

Create the cookbook

  • Navigate to the C:\Chef\…\cookbooks folder and open a Bash window
  • Create an empty cookbook
    chef generate cookbook COOKBOOK_NAME

    Chef creates a new sub-folder with the name of the cookbook.

  • Rename the new folder to cookbook-COOKBOOK_NAME to distinguish it in version control from other repository types.

Update the .gitignore file

  • Chef DK has generated a .gitignore file that contains most of the important entries, but we need to add a few important lines:
    # Certificates
    *.pem
    
    # Unencrypted Data Bags
    data_bags_unencrypted/
    
    # Macintosh folder custom attribute file
    .DS_Store
    
    # If working in a team, personalized Test Kitchen config file 
    .kitchen.yml

Update the metadata.rb file

Add your name, email address, and the version of the cookbook to the top of the metadata.rb file

name 'THE_NAME_OF_THE_COOKBOOK'
maintainer 'YOUR_NAME'
maintainer_email 'YOUR_EMAIL_ADDRESS'
license 'All rights reserved'
description 'Installs/Configures THE_NAME_OF_THE_COOKBOOK'
long_description IO.read(File.join(File.dirname(__FILE__), 'README.md'))
version '1.0.0'

The expression in the long_description line refers to the README.md file that GitHub can create when you set up a new repository. Place the cookbook related information into that file, so others who want to use your cookbook can easily find it.

Update the .kitchen.yml file to be able to test your cookbook.

If you want to test your cookbook in the Cloud, copy the following sections from an existing .kitchen.yml file of your organization. To learn Chef and launch instances with Vagrant on your workstation, the automatically created .kitchen.yml file is perfect.

  • driver
  • provisioner
  • platforms
  • a suite as an example

If your organization use tags to track instances in the Cloud,  update the tags section to reflect the values of the cookbook.

To add multiple recipes to the Chef run list use this syntax:

run_list:
  - recipe[COOKBOOK_NAME1::RECIPE_NAME]
  - recipe[COOKBOOK_NAME2::RECIPE_NAME]

Encrypted Data Bags

If you want to use encrypted data bags, ask your Chef administrator to send you the key file to encrypt and decrypt data bags. In the sample .kitchen.yml file above the DATABAG_SECRET_FILE is the placeholder for the key file name. Create a folder for the key at

C:\Chef\...\data_bags

on the same level where the cookbook and environment folders are.

data-bags-04-secret-file-location

This is a chicken and egg paradox. We don’t want to commit secrets into version control, so we need to encrypt them. But how can we place the secret encryption key on the server to decrypt the secrets? We will use Packer to create our own server images that will contain the secret key, so when Chef starts to run on the server, the key is going to be there.

Default recipe

We will place code in the default.rb file that is common to all recipes in the cookbook. All custom recipes will call the default recipe as the first step.

Update the header comments of the default.rb recipe with your name and company information

#
# Cookbook Name:: COOKBOOK_NAME
# Recipe:: default
#
# Author:: YOUR_NAME (<YOUR_EMAIL_ADDRESS>)
# Copyright (c) 2015-2016 COMPANY_NAME, All Rights Reserved.

Custom recipe

Use the Chef generate command to create the new recipes. It creates all test files in the corect location.

  • Create a new recipe and the test files with
    chef generate recipe MY_RECIPE_NAME
  • Add the following line under the header to call the default recipe, even if it is currently empty
    include_recipe 'COOKBOOK_NAME::default'

Add the cookbook to GitHub

Create the local repository

  • In the Bash window execute the following commands
git init
git add .
git commit -m "Initial commit"

Add the repository to GitHub

In your web browser log into your GitHub account and create a new repository

  • Click the New Repository button
  • Name the repository the same as the name of the folder of the cookbook (cookbook-…)
  • Execute the lines in the section …or push an existing repository….  If you work on a Windows workstation make sure HTTPS is selected
    git remote add origin https://github.com/....git
    git push -u origin master
  • In the Collaborators & teams section of Settings select the group who will have access to the new repository

Test the cookbook

In the Bash window launch the instance with Test Kitchen

List the available instances

kitchen list

Launch the instance

kitchen converge STRING_UNIQUE_TO_THE_INSTANCE

If there are multiple suites or platforms in the .kitchen.yml file you need to type the unique part of the name of the instance to identify it.

Start a Remote Desktop connection to a Windows instance

kitchen login STRING_UNIQUE_TO_THE_INSTANCE

If you work on a Macintosh workstation and testing a Windows server, the best way to remote into the server is

  1. Install Microsoft Remote Desktop for free from the Apple App Store (See the Remote Desktop Client section in Install the DevOps development tools on Macintosh,
  2. Execute the kitchen login STRING_UNIQUE_TO_THE_INSTANCE command in the terminal window,
  3. The Microsoft Remote Desktop window will pop up with the User account name and the IP address. If you click “Connect”, the remote connection opens with the default settings, that are may not optimal for your display. The “login” command already created a new entry in the Microsoft Remote Desktop app with the IP address of the instance. To use custom settings, click Cancel,
  4. Open the Microsoft Remote Desktop app, right click the last entry that contains the IP address, select Edit, and copy the IP address to the clipboard,
  5. Create a new connection with custom display settings and paste the IP address there. You can keep this generic connection to access the Test Kitchen instances, just update the IP address.
  6. Delete the automatically created connection

SSH into a Linux instance

ssh USER_NAME@IP_ADDRESS -i PATH_TO_THE SSH_KEY_FILE

Where

  • USER_NAME is the value of username: in the .kitchen.yml file.
  • IP_ADDRESS is the IP of the instance. Get it from the “Waiting for SSH service on…” line of the Test Kitchen bash or command window, or from the .yml file in the .kitchen/logs folder of the cookbook.
  • PATH_TO_THE_SSH_KEY_FILE is the value of ssh_key: in the .kitchen.yml file.

Terminate the instance

kitchen destroy STRING_UNIQUE_TO_THE_INSTANCE

Upload the cookbook to the Chef server

See Connect to the Chef server in Beginner’s Guide to DevOps Engineering part 4.


Next:

Infrastructure as code in Beginner’s Guide to DevOps Engineering part 6.

Back:

to the Tutorials page

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