You want to ensure your puppet code meets the Puppet Style Guide
Install puppet-lint
# install the newest version of puppet-lint
$ gem install puppet-lint
Fetching: puppet-lint-2.3.0.gem (100%)
Successfully installed puppet-lint-2.3.0
1 gem installed
# show the installed versions
$ gem list puppet-lint
*** LOCAL GEMS ***
puppet-lint (2.3.0)
and run it against your manifests
$ puppet-lint foo.pp
ERROR: foo not in autoload module layout on line 1
WARNING: class not documented on line 1
Any code that fails to pass the Puppet Style Guide recommendations will be shown in the output.
There is a great quote in programming world, "it doesn't matter
which style guide you have, as long as you have one." and this applies
to your puppet code as much as it would any other language. Thanks to
the awesome work done by Tim Sharpe, in the form
of puppet-lint, you can check your code against the Puppet style guide
with nothing more than a gem install and running a single command.
There are a few ways to install puppet-lint, the simplest when
getting started is to use your systems native gem command. As you become
a more advanced user you may want to install it via bundler and a Gemfile
but that is outside the scope of this recipe.
# install the newest version of puppet-lint
$ gem install puppet-lint
Fetching: puppet-lint-2.3.0.gem (100%)
Successfully installed puppet-lint-2.3.0
1 gem installed
# show the installed versions
$ gem list puppet-lint
*** LOCAL GEMS ***
puppet-lint (2.3.0)
Once installed you can run puppet-lint against a single manifest or a
directory of modules, depending on your tolerance for "I have to change
how much?", and read through the exceptions and the corresponding Style Guide
sections.
While you might not see an immediate gain in subjecting yourself to all the changes you'll have to make to be compliant, and in some cases you might disagree with the guide, it's well worth taking the time to read through the exceptions at least once and see where they'd improve your code base. You may get early warnings about features that are being deprecated, edge use cases with sometimes subtle, often unexpected behaviour or even, with the addition of plugins, warnings about insecure behaviour in your resources. The wider puppet community also heavily embraces puppet-lint and most of the third party modules, especially those on the Puppet Forge, will be formatted to be compliant with its checks. If you're planning on getting involved in the wider community knowing the common style is an asset.
The amount of output from an initial run can be daunting, especially if you don't follow the one repository per module pattern, but there are a few ways to help handle the ramp up. You can disable certain checks if you disagree with them:
# don't show manifests failing either of these checks
puppet-lint --no-documentation-check --no-80chars-check modules
You can even start even slower and only enable a few checks at a time:
$ puppet-lint --only-checks 140chars mymodules
mymodules/assets.pp - WARNING: line has more than 140 characters on line 65
Once you decide on which checks you do or don't want to run you can
add them to a .puppet-lint.rc file and check them in alongside your
puppet code to ensure everyone on the team has the same settings:
# puppet-lint will not run
# these checks against your code
$ cat .puppet-lint.rc
--no-140chars-check
--no-documentation-check
--no-star_comments-check
There is also a --fix mode that will attempt to automatically resolve a
number of puppet-lint check failures for you. I'd only recommend running this
if you're keeping your code under version control, being able to diff the
changes it makes is essential. The command itself is simply:
puppet-lint --fix my_module_directory
Once you've become comfortable with the core checks you may decide you
want to enforce some additional extra rules or use other peoples. There
is a community of plugin writers extending puppet-lint in a number of
ways and adding their extensions needs nothing more than a few additional
gem install commands. You can find out more about this in the
Add puppet-lint checks recipe.