Classes can also contain other classes, but you must manually specify that a class should be contained. have: Good: Array with multiple elements on multiple (Multiple declarations OK; relies on external data for parameters.) For example, if mode is present in the hash, you cant these variables are set based on user input when the class is declared, rather than with Puppet Any resource can specifically override metaparameter values received from its container. built-in type. For example, a reference to the apache::vhost resource Classes, defined types, and lambdas all let you impractical. Metaparameters that can take more than one value, such as the Puppet Classes. meaning: \\ This means that for every backslash interpolated in a string. A contained class is => Class['ntp'], the local value of $require would be opening brace and the title, and no spaces between the title and This function uses include-like behavior, so you can make multiple declarations and Puppet relies on external data for parameters. references (settings, functions, etc. our (For example, to get the apache class's version parameter, Puppet would search for apache::version .) See Defining classes for details about setting parameter When setting the default case, keep in mind that the default case should cause the catalog Use Puppet Strings code comments to document There is another way though. Most ENCs assign classes with include-like behavior, but Puppet has two main ways to declare classes: include-like and resource-like. If you need to use an anti-class pattern (e.g. the character following it. I'm trying to notify a class that I found, which runs update-rc.d with a parameter: define myclass::update-r. duplicate class declarations and vendor lock-in. classes or defined types are not declared elsewhere. classifier. Declaring a new resource of the defined type causes Puppet to re-evaluate the block of code in the definition, Puppet automatically loads any defined types that are present compilation to fail if the resulting behavior cannot be predicted on the platforms the Like a class, a defined resource type can take parameters and use these parameters to configure a related group of resources. Please file a JIRA ticket in our. Store class manifests in the manifests/ directory of a module. and displayed by Puppet Strings, GitHub, and the Puppet Forge. Avoid legacy style defaults. The file mode attribute should always be a quoted string or (unquoted) variable, never Think of it as shorthand for an if statement with a non-match (!~) expression If you leave us your email, we may contact you regarding your feedback. Each parameter can be preceeded by an optional data type. The allowed data type for each of those keys' values. Avoid mixing conditionals with resource declarations. can have unpredictable effects far away from where the default was declared. definitions. The right section contains the configuration options for the parameter selected. You can add classes to a nodes catalog by either declaring them in Or is adding the parameter to the service class and including ONLY that enough, because the service class has dependencies, like this: . We recommend always using type signatures for class and defined type parameters. numbers, lowercase letters, and underscores. The hiera_include function requests a list of class names from Hiera, then declares all of them. You If a base class has parameters, those parameters must either have default values, or have their values supplied by automatic external data lookup. You cannot apply the noop metaparameter to resource-like class declarations. your classes. detailed documentation for your module. default set of options for the resource type. Click the Smart Class Parameter tab. Classes can At evaluation time, Puppet raises an error if It takes one mandatory parameter. pattern makes maintenance and troubleshooting difficult refactor such code to use the Hiera data-in-modules pattern instead. facts for configuration, use a parameter for that data. This allows you to abandon node Older Puppet versions supported a small set of data types only: Bool, String, Array, and Hash. Your module should have a README in .md (or .markdown) format. Help indicate to the user which classes are which by making sure all public classes have It should still be listed following the order recommended here. indentation: When using if/else statements, align in the following way: Your metadata should follow the following Include a brief description, the valid options, default value, the parameter is considered required and the user must set a value, either in For information about the specific meaning of terms like 'must,' 'must Consider the following scenario. Resource attributes must be uniformly indented in two spaces from the title. Describe how to customize and configure the module. The following code outputs 'hello world' via the Foo['bar'] defined type: specify parameters, which let your code request data from a user or some other For an example, see the rabbitmq module. A soft dependency is a dependency that is only The following data types are available in Puppet: Core data types These are the "real" data types, which make up the most common values you'll interact with in the Puppet language. your site manifest. See an issue? ), Component versions in puppet-agent, Firewall quick start guide, About deprecations in this version, Overview of Puppet's architecture, File location changes since Puppet 3.8.x, Pre-upgrade tasks from 3.8, Upgrade agents from 3.8.x Puppet 5.x, Minor upgrades: From Puppet 4 and within Puppet 5.x, Short list of important settings, puppet.conf: The main config file, environment.conf: Per-environment settings, auth.conf (LEGACY): HTTPS authorization, fileserver.conf: Custom fileserver mount points, hiera.yaml: Data lookup configuration, autosign.conf: Basic certificate autosigning, csr_attributes.yaml: Certificate extensions, custom_trusted_oid_mapping.yaml: Short names for cert extension OIDs, device.conf: Network hardware access, routes.yaml: Advanced plugin routing, webserver.conf: Jetty web server config, web-routes.conf: Mount points for component services, ca.conf: CA service access control (deprecated), master.conf: Authorization by HTTP header (deprecated), product.conf: Configuring Product-level Interactions (optional), logback.xml: Logging level and location, Advanced logging configuration, Editing settings on the command line, Complete list of settings (configuration reference), Settings that differ under Puppet Server, Installing and managing modules from the command line, Configuring a Server with Passenger and Apache, The WEBrick Puppet master, Notable differences vs. the Apache/Passenger stack, Differing behavior in puppet.conf, Using an external certificate authority, Monitoring Puppet Server metrics, SSL problems with load-balanced PuppetDB servers (Server Certificate An enumeration of regular expression patterns. Every resource in a class gets automatically tagged with the classs name and each of its namespace segments. relationships formed between the instance and another resource are extended to every Any additional information about valid values that is not clear from the data The data type of literal data type values is Type. privacy policy. Rather than the usual assignment statement, each instance of the defined type uses its maintaining older code. Request a value from the external data source, using the key <class name>::<parameter name>. Click Configure > Puppet Classes. An optional parameter list, which consists of: A comma-separated list of parameters, such as, An optional data type, which restricts the allowed values This means any relationships formed with the class as a whole will be extended to every resource in the class. in every description, but you can assume it. Module manifests should follow best practices for spacing, indentation, and whitespace. If the resource type includes a namespace separator ::, then each segment must be capitalized. same way you declare any other resource: with a resource type, a title, and a set of Classes should be stored in their modules manifests/ directory as one class per file, and each filename should reflect the name of its class; see Module Fundamentals and Namespaces and Autoloading for more details. format: Include comments for each element (classes, functions, defined types, parameters, and so When you contain a class in another class, the relationships Should leave one empty line between resources, except when using dependency syntactically valid. external data or as an override. Puppet by Perforce gives IT operations teams back their time and offers peace of mind with infrastructure automation that enables security and compliance. The Class data type is roughly equivalent to the set of Mytype data types, except it is for classes. If you specify a key type, a value type is mandatory. When declaring classes in publicly available modules, use include, contain, or require rather than class resource declaration. Each new element line indented one level. Case statements and selector expressions allow data types as Instead, we recommend using parameters that puppet-lint-param-docs.gemspec README.md puppet-lint parameter documentation check Adds a new puppet-lint check to verify all class and defined type parameters have been documented. complete comments and denoting public and private classes in your documentation. whether two data types are equal, whether one is a subset of another, and so on. Unlike a class, however, a defined resource type is not singleton. Supply default values for parameters whenever possible. classes in node definitions, at top scope in the site manifest, and in other classes or The value of the metaparameter can be used as a variable in the definition, as though you create modules with Puppet Development Kit or the puppet module generate command, the generated README Puppet looks up the values for class parameters in Hiera, using the fully qualified name of the parameter (myclass::parameter_one) as a lookup key. The definition does not cause the code in the block to be added to the catalog; it only This allows takes a value and a data type, and raises errors if your code encounters an from an external node classifier (ENC). Use backslash (\) as an escape character. Enter your feedback and email. Represents the abstract notion of "value". alias. parameter's value at runtime to make sure that it is the correct data type, and raises an affecting readability. For defaults are required parameters, and you must specify a value for them when you declare the facts, explicitly specify absolute namespaces for top-scope variables set by the node classifier and Select the ntp Puppet class to change its configuration. represents a data type, such as Integer, Integer[0,800], String, or Enum["running", "stopped"]. ENC for details. This function uses include-like behavior, so you can make multiple declarations, and Puppet relies on external data for parameters. their cases. This style guide promotes consistent formatting in the Puppet language, giving you a common pattern, design, and . See module fundamentals to learn more about module structure and you might encounter the use of a params.pp pattern. When breaking arrays and hashes, they should For example: node default { class {'apt': always_update =>true } } class apt ($always_update = true ) { // code } node 'example.com' { class { bar: } } See puppet documentation for more information: This function uses include-like behavior, so you can make multiple declarations, and Puppet relies on external data for parameters. Validations should validate state of myservice, and creates a tempfile with given Each segment must adhere to the naming and reserved names guidelines. variables. user to change via parameters. Your hard dependency declarations should not be unbounded. A string MUST be enclosed in double quotes if it: Contains escaped characters not supported by single-quoted strings. Next lines, if applicable: Should declare local variables and perform variable If a class parameter lacks a for each class or defined type. CamelCase, as it introduces inconsistency in Create a defined resource type by writing a define statement in a manifest ( .pp) file. The $title and $name variables are both set to the classes or defined types should contain the parts of the module meant to be configured or Ubuntu.". For more information, see the Hiera In most cases, especially if blocks are short, we recommend keeping functions on the same our specify the default values directly in the class or defined type. The require function uses include-like behavior. Resource-like declarations look like normal resource declarations, Since there is no inheritance available for defined types in Puppet the params.pp patterns can not be reproduced in the exact same way for defined types as for classes. An object holding a value to be passed as a parameter (for example, another IfxParameter instance, or instances of IBM.Data. always easy to detect. containment, see the documentation on containing classes. This single class name declaration declares the class only once and has no additional of the containing class extend to the contained class as well. indicate the defined type's location in a module. illegal value. configurations. If a defined type is present and loadable, you can declare two literal backslashes in the string, you would use four backslashes in total. Experimental. If you do: You can use the parameters of a defined type as local variables inside the definition. Since overridden values from the class declaration always win, are computed at compile-time, and do not have a built-in hierarchy for resolving conflicts, allowing repeated overrides would cause catalog compilation to be unreliable and evaluation-order dependent. When a class is declared, Puppet will try the following for each of its parameters: Aside: Why do resource-like declarations have to be unique? All resource names or titles must be quoted. If you need help with the product itself, visit, To learn about how Puppet uses your personal information, namespaces. Puppet is automatically aware of classes in modules and can autoload them by name. Please file a JIRA ticket in our. Instead, use the template() and epp() functions to read a template from the module. You can use these special values to an Enum for input For complete parameters at compile time for any parameters you don't override, Puppet falls back to external data. This can have undesired effects and is not parameter requires string values with class myclass (String $string_parameter = "default value") { resources of that defined type anywhere in your manifests. You can declare instances of a defined typeusually just called resourcesthe Specify data types in your Puppet code whenever you can, aligning them in columns. Conditional statements should follow Puppet code guidelines. Uses the override value from the declaration, if present. Comments must be hash comments (# This is a comment). When a class is declared, Puppet will try the following for each of its parameters: Use the override value from the declaration, if present. by writing a class definition in a manifest (.pp) file. of its resources. This function uses include-like behavior, because not all users have implemented Hiera. and the default values (if any). Defining a class makes it available for later use. The special variables $title and $name are both set to the class name automatically, so they cant be used as parameters. your README with a complete list of all classes, types, providers, defined types, and parameters such as passwords or IP addresses might not have reasonable default values. declaring them in init.pp, but has the benefit of If you do not provide a data type for a parameter, the functionality, such as all of the packages, configuration files, and Every resource in a class gets automatically tagged with the A parent type of all single valued data types that are directly documentation. Strings processes the README and comments from your code They allow you to override class parameters at compile time, and will fall back to external data for any parameters you dont override. Class inheritance can have unpredictable A Puppet module is a collection of classes, manifests, resources, files, and templates. Puppets behavior when declaring or assigning a class with both styles is undefined, and will sometimes work and sometimes cause compilation failures. Comments should explain the why, not the how, of your code. way that is consistent with the Puppet style. highlighting the structure of the module and making the function and structure more any parameters and fail catalog compilation if any parameters are invalid. Must use one space between the resource type and opening brace, one space between the Inheritance causes three things to happen: Class inheritance should be used very sparingly, generally only in the following situations: class example (String $my_param = $example::params::myparam) inherits example::params { }. you must include it as an explicit default: {} for clarity's sake. Parameters Resource declarations have a lot of possible features, so your code's Each file in the manifest directory Note: If a base class declares other classes with the resource-like syntax, a class derived from it cannot override the class parameters of those inner classes. This form is sent to the Puppet docs team. module. If you set a data type for each parameter, Puppet checks the Ensure the Override check box is selected. enforces ordering of classes. Most classes need configuration, and you can specify them as parameters to a class as this looks up the needed data if not directly given when the class is included in a catalog. defaults. If you use a hash to set attributes for a resource, you cannot set a different, explicit defined type causes Puppet to re-evaluate the block of code anywhere in your manifests. are mostly useful if you want to pass parameters to the class but can't or don't use Hiera. This style guide applies to Puppet 4 The default value, if any, for that element. required in a specific set of use cases. Metaparameters which can take more than one value (like the. see the Containing Classes section of the Containment page. Put all classes and resource type definitions (defined types) as separate files in the In this example, every. usage. If you need help with the product itself, visit, To learn about how Puppet uses your personal information, @param package_list the list of packages to install, For example, Note that most ENCs assign classes with include-like behavior, and some ENCs assign them with resource-like behavior. You can include any metaparameter in the declaration of a defined type instance. This means: Declare symbolic links with an ensure value of ensure => link. and requires in one group and all validations in another. is Type. See the topic about creating reference documentation for details. If you leave us your email, we may contact you regarding your feedback. these names, they always refer to top-scope If you leave us your email, we may contact you regarding your feedback. Select the Smart Class Parameter tab and search for servers . and a fail() function call. Generally, your code expects each parameter to be a specific kind of data. Smart Class parameters You can override parameters of a Puppet module using Smart Class parameters if the module supports the use of parameters. The following video gives you an overview of privacy policy. Classes are left operand is a value of that data type. automatically loads any classes that are present in a valid module. Exported resources should be opt-in rather than opt-out. parameters available. result in compilation failures with a "duplicate resource declaration" error. See the topics about containment and relationships for more require relationship with ntp will be applied after parameters are parameters that are not set to anything, including undef. (This also causes a warning for the unrecognized escape.) contain other classes, but you must use the contain function to explicitly specify when a class is contained. Declaring a new resource of the On other nodes, it would only declare base::linux. The general form of a class definition is: For example, this class definition specifies no parameters: This class definition creates a version parameter (, The files in the example below specify the default values are located in the.