group Resource
This page is generated from the Chef Infra Client source code.To suggest a change, edit the group.rb file and submit a pull request to the Chef Infra Client repository.
Use the group resource to manage a local group.
Syntax
The full syntax for all of the properties that are available to the group resource is:
group 'name' do
append true, false # default value: false
comment String
excluded_members String, Array # default value: []
gid String, Integer
group_name String # default value: 'name' unless specified
members String, Array # default value: []
non_unique true, false # default value: false
system true, false # default value: false
action Symbol # defaults to :create if not specified
end
where:
group
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.append
,comment
,excluded_members
,gid
,group_name
,members
,non_unique
, andsystem
are the properties available to this resource.
Actions
The group resource has the following actions:
:create
- (default) Create a group. If a group already exists (but does not match), update that group to match.
:manage
- Manage an existing group. This action does nothing if the group does not exist.
:modify
- Modify an existing group. This action raises an exception if the group does not exist.
: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.
:remove
- Remove a group.
Properties
The group resource has the following properties:
append
- Ruby Type: true, false | Default Value:
false
How members should be appended and/or removed from a group. When true,
members
are appended andexcluded_members
are removed. Whenfalse
, group members are reset to the value of themembers
property.
comment
- Ruby Type: String
Specifies a comment to associate with the local group.
New in Chef Client 14.9
excluded_members
- Ruby Type: String, Array | Default Value:
[]
Remove users from a group. May only be used when
append
is set totrue
.
gid
- Ruby Type: String, Integer
The identifier for the group.
group_name
- Ruby Type: String | Default Value:
The resource block's name
The name of the group. Default value: the
name
of the resource block. See “Syntax” section above for more information.
members
- Ruby Type: String, Array | Default Value:
[]
Which users should be set or appended to a group. When more than one group member is identified, the list of members should be an array:
members ['user1', 'user2']
.
non_unique
- Ruby Type: true, false | Default Value:
false
Allow gid duplication. May only be used with the
Groupadd
user resource provider.
system
- Ruby Type: true, false | Default Value:
false
Set to
true
if the group belongs to a system group.
Common Resource Functionality
Chef resources include common properties, notifications, and resource guards.
Common Properties
The following properties are common to every resource:
compile_time
Ruby Type: true, false | Default Value:
false
Control the phase during which the resource is run on the node. Set to true to run while the resource collection is being built (the
compile phase
). Set to false to run while Chef Infra Client is configuring the node (theconverge phase
).ignore_failure
Ruby Type: true, false, :quiet | Default Value:
false
Continue running a recipe if a resource fails for any reason.
:quiet
will not display the full stack trace and the recipe will continue to run if a resource fails.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 delay in seconds between retry attempts.
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 anotifies
statement for each resource to be notified.If the referenced resource does not exist, an error is raised. In contrast,
subscribes
will not fail if the source resource is not found.
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, for each 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.
If the other resource does not exist, the subscription will not raise an
error. Contrast this with the stricter semantics of notifies
, which
will raise an error if the other resource does not exist.
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, for each 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 returntrue
in addition to0
. - A block is executed as Ruby code that must return either
true
orfalse
. If the block returnstrue
, the guard property is applied. If the block returnsfalse
, 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.
PropertiesThe 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
.
Examples
The following examples demonstrate various approaches for using the group resource in recipes:
The following examples demonstrate various approaches for using the group resource in recipes:
Append users to groups:
group 'www-data' do
action :modify
members 'maintenance'
append true
end
Add a user to group on the Windows platform:
group 'Administrators' do
members ['domain\foo']
append true
action :modify
end