Chef Development Kit

Chef Development Kit (ChefDK) brings Chef and the development tools developed by the Chef Community together and acts as the consistent interface to this awesomeness. This awesomeness is composed of:

This repository contains the code for the chef command. The full package is built with omnibus. Project and component build definitions are in the omnibus directory in this repository.

Installation

You can get the latest release of ChefDK from the downloads page.

On Mac OS X, you can also use homebrew-cask to brew cask install chefdk.

Once you install the package, the chef-client suite, berks, kitchen, and this application (chef) will be symlinked into your system bin directory, ready to use.

Pre-release Candidates

The following commands will download the latest ChefDK package from the current channel. The current channel holds builds that have passed testing and are candidates for release.

Linux and OS/X:

In a terminal, run:

curl https://omnitruck.chef.io/install.sh | sudo bash -s -- -c current -P chefdk

To download a specific version, append the -v flag. EG, -v 0.9.0.

Windows

Open up a Powershell command prompt as Administrator and run:

. { iwr -useb https://omnitruck.chef.io/install.ps1 } | iex; install -channel current -project chefdk

To download a specific version, append the -version flag. EG, -version 0.9.0.

Usage

For help with Berkshelf, Test Kitchen, ChefSpec or Foodcritic, visit those projects' homepages for documentation and guides. For help with chef-client and knife, visit the Chef documentation and Learn Chef.

The chef Command

Our goal is for chef to become a workflow tool that builds on the ideas of Berkshelf to provide an awesome experience that encourages quick iteration and testing (and makes those things easy) and provides a way to easily, reliably, and repeatably roll out new automation code to your infrastructure.

While we've got a long way to go before we reach that goal we do have some helpful bits of functionality already included in the chef command:

chef generate

The generate subcommand generates skeleton Chef code layouts so you can skip repetitive boilerplate and get down to automating your infrastructure quickly. Unlike other generators, it only generates the minimum required files when creating a cookbook so you can focus on the task at hand without getting overwhelmed by stuff you don't need.

The following generators are built-in:

  • chef generate app Creates an "application" layout that supports multiple cookbooks. This is a somewhat experimental compromise between the one-repo-per-cookbook and monolithic-chef-repo styles of cookbook management.

  • chef generate cookbook Creates a single cookbook.

  • chef generate recipe Creates a new recipe file in an existing cookbook.

  • chef generate attribute Creates a new attributes file in an existing cookbook.

  • chef generate template Creates a new template file in an existing cookbook. Use the -s SOURCE option to copy a source file's content to populate the template.

  • chef generate file Creates a new cookbook file in an existing cookbook. Supports the -s SOURCE option similar to template.

  • chef generate lwrp Creates a new LWRP resource and provider in an existing cookbook.

The chef generate command also accepts additional --generator-arg key=value pairs that can be used to supply ad-hoc data to a generator cookbook. For example, you might specify --generator-arg database=mysql and then only write a template for recipes/mysql.rb if context.database == 'mysql'.

chef gem

chef gem is a wrapper command that manages installation and updating of rubygems for the Ruby installation embedded in the ChefDK package. This allows you to install knife plugins, Test Kitchen drivers, and other Ruby applications that are not packaged with ChefDK.

Gems are installed to a .chefdk directory in your home directory; any executables included with a gem you install will be created in ~/.chefdk/gem/ruby/2.1.0/bin. You can run these executables with chef exec, or use chef shell-init to add ChefDK's paths to your environment. Those commands are documented below.

chef exec

chef exec <command> runs any arbitrary shell command with the PATH environment variable and the ruby environment variables (GEM_HOME, GEM_PATH, etc.) setup to point at the embedded ChefDK omnibus environment.

chef shell-init

chef shell-init SHELL_NAME emits shell commands that modify your environment to make ChefDK your primary ruby. It supports bash, zsh, fish and PowerShell (posh). For more information to help you decide if this is desirable and instructions, see "Using ChefDK as Your Primary Development Environment" below.

chef install

chef install reads a Policyfile.rb document, which contains a run_list and optional cookbook version constraints, finds a set of cookbooks that provide the desired recipes and meet dependency constraints, and emits a Policyfile.lock.json describing the expanded run list and locked cookbook set. The Policyfile.lock.json can be used to install the cookbooks on another machine. The policy lock can be uploaded to a Chef Server (via the chef push command) to apply the expanded run list and locked cookbook set to nodes in your infrastructure. See the POLICYFILE_README.md for further details.

chef push

chef push POLICY_GROUP uploads a Policyfile.lock.json along with the cookbooks it references to a Chef Server. The policy lock is applied to a POLICY_GROUP, which is a set of nodes that share the same run list and cookbook set. This command operates in compatibility mode and has the same caveats as chef install. See the POLICYFILE_README.md for further details.

chef update

chef update updates a Policyfile.lock.json with the latest cookbooks from upstream sources. It supports an --attributes flag which will cause only attributes from the Policyfile.rb to be updated.

chef diff

chef diff shows an itemized diff between Policyfile locks. It can compare Policyfile locks from local disk, git, and/or the Chef Server, based on the options given.

chef verify

chef verify tests the embedded applications. By default it runs a quick "smoke test" to verify that the embedded applications are installed correctly and can run basic commands. As an end user this is probably all you'll ever need, but verify can also optionally run unit and integration tests by supplying the --unit and --integration flags, respectively.

WARNING: The integration tests will do dangerous things like start HTTP servers with access to your filesystem and even create users and groups if run with sufficient privileges. The tests may also be sensitive to your machine's configuration. If you choose to run these, we recommend to only run them on dedicated, isolated hosts (we do this in our build cluster to verify each build).

Using ChefDK as Your Primary Development Environment

By default, ChefDK only adds a few select applications to your PATH and packages them in such a way that they are isolated from any other Ruby development tools you have on your system. If you're happily using your system ruby, rvm, rbenv, chruby or any other development environment, you can continue to do so. Just ensure that the ChefDK provided applications appear first in your PATH before any gem-installed versions and you're good to go.

If you'd like to use ChefDK as your primary Ruby/Chef development environment, however, you can do so by initializing your shell with ChefDK's environment.

To try it temporarily, in a new terminal session, run:

eval "$(chef shell-init SHELL_NAME)"

where SHELL_NAME is the name of your shell (usually bash, but zsh is also common). This modifies your PATH and GEM_* environment variables to include ChefDK's paths (run without the eval to see the generated code). Now your default ruby and associated tools will be the ones from ChefDK:

which ruby
# => /opt/chefdk/embedded/bin/ruby

To add ChefDK to your shell's environment permanently, add the initialization step to your shell's profile:

echo 'eval "$(chef shell-init SHELL_NAME)"' >> ~/.YOUR_SHELL_PROFILE

Where YOUR_SHELL_PROFILE is ~/.bash_profile for most bash users, ~/.zshrc for zsh, and ~/.bashrc on Ubuntu.

Powershell

You can use chef shell-init with PowerShell on Windows.

To try it in your current session:

chef shell-init powershell | Invoke-Expression

To enable it permanently:

"chef shell-init powershell | Invoke-Expression" >> $PROFILE

Fish

chef shell-init also supports fish.

To try it:

eval (chef shell-init fish)

To permanently enable:

echo 'eval (chef shell-init SHELL_NAME)' >> ~/.config/fish/config.fish

Uninstallation Instructions

Mac OS X

You can uninstall Chef Development Kit on Mac using the below commands.

First, remove the main package files:

# Remove the installed files
sudo rm -rf /opt/chefdk

# Remove the system installation entry
sudo pkgutil --forget com.getchef.pkg.chefdk

Next, remove the symlinks which the Chef Development Kit installs. The location for these differs based on your OS X version.

Pre-El Capitan:

# Symlinks are in /usr/bin
ls -la /usr/bin | egrep '/opt/chefdk' | awk '{ print $9 }' | sudo xargs -I % rm -f /usr/bin/%

Post-El Capitan:

# Symlinks are in /usr/local/bin
ls -la /usr/local/bin | egrep '/opt/chefdk' | awk '{ print $9 }' | sudo xargs -I % rm -f /usr/local/bin/%

Windows

You can use Add / Remove Programs on Windows to remove the Chef Development Kit from your system.

RHEL

You can use rpm to uninstall Chef Development Kit on RHEL based systems:

rpm -qa *chefdk*
yum remove <package>
rm -rf /opt/chefdk
rm -rf ~/.chefdk

Ubuntu

You can use dpkg to uninstall Chef Development Kit on Ubuntu based systems:

dpkg --list | grep chefdk # or dpkg --status chefdk

# Purge chefdk from the system.
# see man dkpg for details
dpkg -P chefdk

For ChefDK Developers

Building the ChefDK

To build the chef-dk, we use the omnibus system. Go to the omnibus README to find out how to build!

Updating Dependencies

If you want to change our constraints (change which packages and versions we accept in the chef-dk), there are several places to do so:

Once you've made any changes you want, you have to update the lockfiles that actually drive the build:

  • To update the chef-dk's dependencies to the very latest versions available, run rake bundle:update.
  • To update the chef-dk's dependencies conservatively (changing as little as possible), run rake bundle:install.
  • To update specific gems only, run rake bundle:update[gem1 gem2 ...]
  • bundle update and bundle install will not work, on purpose: the rake task handles both the windows and non-windows lockfiles and updates them in sync.

*

To perform a full update of all dependencies everywhere, run rake dependencies. This will update the Gemfile.lock, Gemfile.windows.lock, omnibus/Gemfile.lock, acceptance/Gemfile.lock, omnibus/Berksfile.lock, and omnibus_overrides.rb. It will also show you any outdated dependencies due to conflicting constraints. Some outdated dependencies are to be expected; it will inform you if any new ones appear that we don't know about, and tell you how to proceed.

How the ChefDK Builds and Versions

The ChefDK is an amalgam of many components. These components update all the time, necessitating new builds. This is an overview of the process of versioning, building and releasing the ChefDK.

ChefDK Packages

The ChefDK is distributed as packages for debian, rhel, ubuntu, windows and os/x. It includes a large number of components from various sources, and these are versioned and maintained separately from the chef-dk project, which bundles them all together conveniently for the user.

These packages go through several milestones:

  • master: When code is checked in to master, the patch version of chef-dk is bumped (e.g. 0.9.10 -> 0.9.11) and a build is kicked off automatically to create and test the packages in Chef's Jenkins cluster.
  • unstable: When a package is built, it enters the unstable channel. When all packages for all OS's have successfully built, the test phase is kicked off in Jenkins across all supported OS's. These builds are password-protected and generally only available to the test systems.
  • current: If the packages pass all the tests on all supported OS's, it is promoted as a unit to current, and is available via Chef's artifactory by running curl https://omnitruck.chef.io/install.sh | sudo bash -s -- -c current -P chefdk
  • stable: Periodically, Chef will pick a release to "bless" for folks who would like a slower update schedule than "every time a build passes the tests." When this happens, it is manually promoted to stable and an announcement is sent to the list. It can be reached at https://downloads.chef.io or installed using the curl command without specifying -c current. Packages in stable are no longer available in current.

Additionally, periodically Chef will update the desired versions of chef-dk components and check that in to master, triggering a new build with the updated components in it.

Automated Version Bumping

Whenever a change is checked in to master, the patch version of chef-dk is bumped. To do this, the lita-versioner bot listens to github for merged PRs, and when it finds one, takes these actions:

  1. Bumps the patch version in lib/chef-dk/version.rb (e.g. 0.9.14 -> 0.9.15).
  2. Runs rake dependencies:update_conservative to update the Gemfile.lock and Gemfile.windows.lock to include the new version.
  3. Pushes to master and submits a new build to Chef's Jenkins cluster.

Component Versions

The chef-dk has two sorts of component: ruby components like berkshelf and test-kitchen, and binary components like openssl and even ruby itself.

In general, you can find all chef-dk desired versions in the Gemfile and version_policy.rb files. The Gemfile.lock is the locked version of the Gemfile, and omnibus_overrides is the locked version of omnibus. build and test Gemfiles and Berksfile version the toolset we use to build and test.

Binary Components

The versions of binary components (as well as rubygems and bundler, which can't be versioned in a Gemfile) are stored in version_policy.rb (the OMNIBUS_OVERRIDES constant) and locked in omnibus_overrides. rake dependencies will update the bundler version, and the rest are be updated manually by Chef every so often.

These have software definitions either in omnibus/config/software or, more often, in the omnibus-software project.

Rubygems Components

Most of the actual front-facing software in the chef-dk is composed of ruby projects. berkshelf, test-kitchen and even chef itself are made of ruby gems. Chef uses the typical ruby way of controlling rubygems versions, the Gemfile. Specifically, the Gemfile at the top of the chef-dk repository governs the version of every single gem we install into the chef-dk package. It's a one-stop shop.

Our rubygems component versions are locked down with Gemfile.lock and Gemfile.windows.lock (which affects windows), and can be updated with rake dependencies.

There are three gems versioned outside the Gemfile: rubygems, bundler and chef. rubygems and bundler are in the RUBYGEMS_AT_LATEST_VERSION constant in version_policy.rb and locked in omnibus_overrides. chef's version is stored in the Gemfile and pins to the latest current build of chef (the latest one to pass tests). They are kept up to date by rake dependencies.

Windows: Gemfile.lock is generated platform-agnostic. In order to keep windows versions in sync, Gemfile.windows reads the generic Gemfile.lock and explicitly pins all gems to those versions, allowing bundler to bring in windows-specific versions of the gems and new deps, but requiring that all gems shared between Windows and Unix have the same version.

The tool we use to generate Windows-specific lockfiles on non-Windows machines is tasks/bin/bundle-platform, which takes the first argument and sets Gem.platforms, and then calls bundle with the remaining arguments.

Build Tooling Versions

Of special mention is the software we use to build omnibus itself. There are two distinct bits of code that control the versions of compilers, make, git, and other tools we use to build.

First, the Jenkins machines that run the build are configured entirely by the opscode-ci cookbook cookbook. They install most of the tools we use via build-essentials, and standardize the build environment so we can tear down and bring up builders at will. These machines are kept alive long-running, are periodically updated by Chef to the latest opscode-ci, omnibus and build-essentials cookbooks.

Second, the version of omnibus we use to build the chef-dk is governed by omnibus/Gemfile. When software definitions or the omnibus framework is updated, this is the file that drives whether we pick it up.

The omnibus tooling versions are locked down with omnibus/Gemfile.lock, and can be updated by running rake dependencies.

Test Versions

chef-dk is tested by the chef-acceptance framework, which contains suites that are run on the Jenkins test machines. The definitions of the tests are in the acceptance directory. The version of chef-acceptance and test-kitchen, are governed by acceptance/Gemfile.

The test tooling versions are locked down with acceptance/Gemfile.lock, which can be updated by running rake dependencies.

The Build Process

The actual ChefDK build process is done with Omnibus, and has several general steps:

  1. bundle install from chef-dk/Gemfile.lock
  2. Reinstall any gems that came from git or path using rake install
  3. appbundle chef, chef-dk, test-kitchen and berkshelf
  4. Put miscellaneous powershell scripts and cleanup

Kicking Off The Build

The build is kicked off in Jenkins by running this on the machine (which is already the correct OS and already has the correct dependencies, loaded by the omnibus cookbook):

load-omnibus-toolchain.bat
cd chef-dk/omnibus
bundle install
bundle exec omnibus build chefdk

This causes the chefdk project definition to load, which runs the chef-dk-complete software definition, the primary software definition driving the whole build process. The reason we embed it all in a software definiton instead of the project is to take advantage of omnibus caching: omnibus will invalidate the entire project (and recompile ruby, openssl, and everything else) if you change anything at all in the project file. Not so with a software definition.

Installing the Gems

The primary build definition that installs the many ChefDK rubygems is software/chef-dk.rb. This has dependencies on any binary libraries, ruby, rubygems and bundler. It has a lot of steps, so it uses a library to help reuse code and make it manageable to look at.

What it does:

  1. Depends on software defs for pre-cached gems (see "Gems and Caching" below).
  2. Installs all gems from the bundle:
    • Sets up a .bundle/config (code) with --retries=4, --jobs=1, --without=development,no_, and build.config.nokogiri to pass.
    • Sets up a common environment, standardizing the compilers and flags we use, in env.
    • Runs bundle install --verbose
  3. Reinstalls any gems that were installed via path:
    • Runs bundle list --paths to get the installed directories of all gems.
    • For each gem not installed in the main gem dir, runs rake install from the installed gem directory.
    • Deletes the bundler git cache and path- and git-installed gems from the build.
  4. Creates /opt/chefdk/Gemfile and /opt/chefdk/Gemfile.lock with the gems that were installed in the build.

Gems and Caching

Some gems take a super long time to install (particularly native-compiled ones such as nokogiri and dep-selector-libgecode) and do not change version very often. In order to avoid doing this work every time, we take advantage of omnibus caching by separating out these gems into their own software definitions. chef-dk-gem-dep-selector-libgecode for example.

Each of these gems uses the config/files/chef-dk-gem/build-chef-dk-gem library to define itself. The name of the software definition itself indicates the .

We only create software definitions for long-running gems. Everything else is just installed in the chef-dk software definition in a big bundle install catchall.

Most gems we just install in the single chef-dk software definition.

The first thing

Appbundling

After the gems are installed, we appbundle them in chef-dk-appbundle. This creates binstubs that use the bundle to pin the software .

During the process of appbundling, we update the gem's Gemfile to include the locks in the top level /opt/chefdk/Gemfile.lock, so we can guarantee they will never pick up things outside the build. We then run bundle lock to update the gem's Gemfile.lock, and bundle check to ensure all the gems are actually installed. The appbundler then uses these pins.

Other Cleanup

Finally, the chef-dk does several more steps including installing powershell scripts and shortcuts, and removing extra documentation to keep the build slim.