Functions

OpenVox has a number of built-in functions for loading external data, iteration, logging, manipulating data, and more. This chapter covers the most important ones; the full list is in the built-in function reference.

Template and file functions

epp

The epp function loads and evaluates an EPP template from a module's templates directory:

epp('module_name/filename', { parameter => value, })

epp

inline_epp

The inline_epp function evaluates a string containing an EPP template:

inline_epp('template string', { parameter => value, })

inline_epp

template

The template function loads and evaluates an ERB template from a module's templates directory:

template('module_name/filename')

template

inline_template

The inline_template function evaluates a string containing an ERB template:

inline_template('template string')

inline_template

file

The file function loads a file from a module's files directory:

file('module_name/filename')

file

Logging and failure

Logging

OpenVox supports a number of functions for logging on the server evaluating Puppet code. Each takes a string argument that is logged at an escalating log level:

• debug
• info
• notice
• warning
• err
• alert
• crit
• emerg

fail

The fail function causes an immediate catalog compilation failure. Any parameters passed to the function appear in the resulting stack trace.

fail

Iteration

each

each is the most common native iteration function. Given an Iterable data type (such as Array or Hash), each loops over each value and runs a lambda against it:

$array.each |$value| { # Code block }
$hash.each |$key, $value| { # Code block }

each · Iterative functions · Lambdas

create_resources

In older versions of Puppet (pre-Puppet 4) that lacked native iteration, the create_resources function was used to create resources from a hash:

$pkg = {
  'vim' => {
    'ensure' => 'installed',
  },
  'emacs' => {
    'ensure' => 'absent',
  },
}

create_resources('package', $pkg)

With native iteration, the following replaces the create_resources call:

$pkg.each |$key, $value| {
  package { $key:
    * => $value,
  }
}

Flow control

OpenVox supports the following functions for exiting a loop:

• break
• next
• return

Functions that take a lambda

• all
• any
• filter
• map
• reduce
• reverse_each
• sort
• with

Declaring classes

• include adds a class and its resources to a catalog.
• require declares a class, but also adds a dependency on the required class.
• contain declares a class, including all of its resources as if they were defined in the current class.

Warning

include is the only completely safe way to declare a class from multiple different classes.

Another way to declare a class is with a resource-like class declaration, which is useful for explicitly specifying class parameters as resource attributes:

class { 'classname':
  parameter => 'value',
}

Like any normal resource, duplicate class declarations cause a catalog compilation failure.

Declaring classes

defined

defined determines whether a class, resource type, or variable is available, or whether a resource is declared in a catalog:

defined('typename')
defined('classname')
defined('$variable')
defined(Resource['name'])

defined

Other functions

There are many more built-in functions. A selection:

annotate	empty	hocon_data	new	step
assert_type	eyaml_lookup_key	import	partition	strftime
binary_file	find_file	index	realize	strip
call	flatten	join	regsubst	tag
camelcase	floor	json_data	round	tagged
capitalize	fqdn_rand	keys	rstrip	then
ceiling	generate	length	scanf	tree_each
chomp	get	lest	sha1	type
chop	getvar	lstrip	sha256	unique
compare	group_by	match	shellquote	unwrap
convert_to	hiera	max	size	upcase
dig	hiera_array	md5	slice	values
digest	hiera_hash	min	split	versioncmp
downcase	hiera_include	module_directory	sprintf	yaml_data