yum_package resource¶

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Use the yum_package resource to install, upgrade, and remove packages with Yum for the Red Hat and CentOS platforms. The yum_package resource is able to resolve provides data for packages much like Yum can do when it is run from the command line. This allows a variety of options for installing packages, like minimum versions, virtual provides, and library names.

Note

Support for using file names to install packages (as in yum_package "/bin/sh") is not available because the volume of data required to parse for this is excessive.

Note

In many cases, it is better to use the package resource instead of this one. This is because when the package resource is used in a recipe, Chef Infra Client will use details that are collected by Ohai at the start of a Chef Infra Client run to determine the correct package application. Using the package resource allows a recipe to be authored in a way that allows it to be used across many platforms.

Syntax¶

A yum_package resource block manages a package on a node, typically by installing it. The simplest use of the yum_package resource is:

yum_package 'package_name'

which will install the named package using all of the default options and the default action (:install).

The yum_package resource has the following syntax:

yum_package 'name' do
  allow_downgrade      true, false # default value: true
  arch                 String, Array
  flush_cache          Hash # default value: {"before"=>false, "after"=>false}
  options              String, Array
  package_name         String, Array
  source               String
  timeout              String, Integer
  version              String, Array
  yum_binary           String
  action               Symbol # defaults to :install if not specified
end

where:

yum_package is the resource.
name is the name given to the resource block.
action identifies which steps Chef Infra Client will take to bring the node into the desired state.
allow_downgrade, arch, flush_cache, options, package_name, source, timeout, version, and yum_binary are the properties available to this resource.

Actions¶

The yum_package resource has the following actions:

:install: Default. Install a package. If a version is specified, install the specified version of the package.
:lock: Locks the yum package to a specific version.
:nothing: This resource block does not act unless notified by another resource to take action. Once notified, this resource block either runs immediately or is queued up to run at the end of a Chef Infra Client run.
:purge: Purge a package. This action typically removes the configuration files as well as the package.
:remove: Remove a package.
:unlock: Unlocks the yum package so that it can be upgraded to a newer version.
:upgrade: Install a package and/or ensure that a package is the latest version. This action will ignore the version attribute.
:nothing: This resource block does not act unless notified by another resource to take action. Once notified, this resource block either runs immediately or is queued up to run at the end of a Chef Infra Client run.

Properties¶

The yum_package resource has the following properties:

allow_downgrade

Ruby Type: true, false | Default Value: true

Downgrade a package to satisfy requested version requirements.

arch

Ruby Type: String, Array

The architecture of the package to be installed or upgraded. This value can also be passed as part of the package name.

flush_cache

Ruby Type: Hash | Default Value: {"before"=>false, "after"=>false}

Flush the in-memory cache before or after a Yum operation that installs, upgrades, or removes a package. Accepts a Hash in the form: { :before => true/false, :after => true/false } or an Array in the form [ :before, :after ].

Yum automatically synchronizes remote metadata to a local cache. Chef Infra Client creates a copy of the local cache, and then stores it in-memory during a Chef Infra Client run. The in-memory cache allows packages to be installed during a Chef Infra Client run without the need to continue synchronizing the remote metadata to the local cache while the Chef Infra Client run is in-progress.

As an array:

yum_package 'some-package' do
  #...
  flush_cache [ :before ]
  #...
end

and as a Hash:

yum_package 'some-package' do
  #...
  flush_cache( { :after => true } )
  #...
end

Note

The flush_cache property does not flush the local Yum cache! Use Yum tools—yum clean headers, yum clean packages, yum clean all—to clean the local Yum cache.

options

Ruby Type: String, Array

One (or more) additional command options that are passed to the command.

package_name

Ruby Type: String, Array

One of the following: the name of a package, the name of a package and its architecture, the name of a dependency. Default value: the name of the resource block. See “Syntax” section above for more information.

source

Ruby Type: String

The optional path to a package on the local file system.

timeout

Ruby Type: String, Integer

The amount of time (in seconds) to wait before timing out.

version

Ruby Type: String, Array

The version of a package to be installed or upgraded. This property is ignored when using the :upgrade action.

yum_binary

Ruby Type: String

Common Resource Functionality¶

Chef resources include common properties, notifications, and resource guards.

Common Properties¶

The following properties are common to every resource:

ignore_failure

Ruby Type: true, false | Default Value: false

Continue running a recipe if a resource fails for any reason.

retries

Ruby Type: Integer | Default Value: 0

The number of attempts to catch exceptions and retry the resource.

retry_delay

Ruby Type: Integer | Default Value: 2

The retry delay (in seconds).

sensitive

Ruby Type: true, false | Default Value: false

Ensure that sensitive resource data is not logged by Chef Infra Client.

Notifications¶

notifies

Ruby Type: Symbol, ‘Chef::Resource[String]’

A resource may notify another resource to take action when its state changes. Specify a 'resource[name]', the :action that resource should take, and then the :timer for that action. A resource may notify more than one resource; use a notifies statement for each resource to be notified.

A timer specifies the point during a Chef Infra Client run at which a notification is run. The following timers are available:

:before: Specifies that the action on a notified resource should be run before processing the resource block in which the notification is located.
:delayed: Default. Specifies that a notification should be queued up, and then executed at the end of a Chef Infra Client run.
:immediate, :immediately: Specifies that a notification should be run immediately, per resource notified.

The syntax for notifies is:

notifies :action, 'resource[name]', :timer

subscribes: Ruby Type: Symbol, ‘Chef::Resource[String]’

A resource may listen to another resource, and then take action if the state of the resource being listened to changes. Specify a 'resource[name]', the :action to be taken, and then the :timer for that action.

Note that subscribes does not apply the specified action to the resource that it listens to - for example:

file '/etc/nginx/ssl/example.crt' do
  mode '0600'
  owner 'root'
end

service 'nginx' do
  subscribes :reload, 'file[/etc/nginx/ssl/example.crt]', :immediately
end

In this case the subscribes property reloads the nginx service whenever its certificate file, located under /etc/nginx/ssl/example.crt, is updated. subscribes does not make any changes to the certificate file itself, it merely listens for a change to the file, and executes the :reload action for its resource (in this example nginx) when a change is detected.

A timer specifies the point during a Chef Infra Client run at which a notification is run. The following timers are available:

:before: Specifies that the action on a notified resource should be run before processing the resource block in which the notification is located.
:delayed: Default. Specifies that a notification should be queued up, and then executed at the end of a Chef Infra Client run.
:immediate, :immediately: Specifies that a notification should be run immediately, per resource notified.

The syntax for subscribes is:

subscribes :action, 'resource[name]', :timer

Guards¶

A guard property can be used to evaluate the state of a node during the execution phase of a Chef Infra Client run. Based on the results of this evaluation, a guard property is then used to tell Chef Infra Client if it should continue executing a resource. A guard property accepts either a string value or a Ruby block value:

A string is executed as a shell command. If the command returns 0, the guard is applied. If the command returns any other value, then the guard property is not applied. String guards in a powershell_script run Windows PowerShell commands and may return true in addition to 0.
A block is executed as Ruby code that must return either true or false. If the block returns true, the guard property is applied. If the block returns false, the guard property is not applied.

A guard property is useful for ensuring that a resource is idempotent by allowing that resource to test for the desired state as it is being executed, and then if the desired state is present, for Chef Infra Client to do nothing.

Properties

The following properties can be used to define a guard that is evaluated during the execution phase of a Chef Infra Client run:

not_if: Prevent a resource from executing when the condition returns true.
only_if: Allow a resource to execute only if the condition returns true.

Multiple Packages¶

A resource may specify multiple packages and/or versions for platforms that use Yum, DNF, Apt, Zypper, or Chocolatey package managers. Specifying multiple packages and/or versions allows a single transaction to:

Download the specified packages and versions via a single HTTP transaction
Update or install multiple packages with a single resource during a Chef Infra Client run

For example, installing multiple packages:

package %w(package1 package2)

Installing multiple packages with versions:

package %w(package1 package2) do
  version [ '1.3.4-2', '4.3.6-1']
end

Upgrading multiple packages:

package %w(package1 package2)  do
  action :upgrade
end

Removing multiple packages:

package %w(package1 package2)  do
  action :remove
end

Purging multiple packages:

package %w(package1 package2)  do
  action :purge
end

Notifications, via an implicit name:

package %w(package1 package2)  do
  action :nothing
end

log 'call a notification' do
  notifies :install, 'package[package1, package2]', :immediately
end

Note

Notifications and subscriptions do not need to be updated when packages and versions are added or removed from the package_name or version properties.

Examples¶

The following examples demonstrate various approaches for using resources in recipes:

Install an exact version

yum_package 'netpbm = 10.35.58-8.el5'

Install a minimum version

yum_package 'netpbm >= 10.35.58-8.el5'

Install a minimum version using the default action

yum_package 'netpbm'

To install a package

yum_package 'netpbm' do
  action :install
end

To install a partial minimum version

yum_package 'netpbm >= 10'

To install a specific architecture

yum_package 'netpbm' do
  arch 'i386'
end

or:

yum_package 'netpbm.x86_64'

To install a specific version-release

yum_package 'netpbm' do
  version '10.35.58-8.el5'
end

Handle cookbook_file and yum_package resources in the same recipe

When a cookbook_file resource and a yum_package resource are both called from within the same recipe, use the flush_cache attribute to dump the in-memory Yum cache, and then use the repository immediately to ensure that the correct package is installed:

cookbook_file '/etc/yum.repos.d/custom.repo' do
  source 'custom'
  mode '0755'
end

yum_package 'only-in-custom-repo' do
  action :install
  flush_cache [ :before ]
end