ohai_hint resource¶
Use the ohai_hint resource to aid in configuration detection by passing hint data to Ohai.
New in Chef Client 14.0.
Syntax¶
The ohai_hint resource has the following syntax:
ohai_hint 'name' do
compile_time true, false # default value: true
content Hash
hint_name String # default value: 'name' unless specified
action Symbol # defaults to :create if not specified
end
where:
ohai_hint
is the resource.name
is the name given to the resource block.action
identifies which steps the chef-client will take to bring the node into the desired state.compile_time
,content
, andhint_name
are the properties available to this resource.
Actions¶
The ohai_hint resource has the following actions:
:create
- Default. Create an Ohai hint file.
:delete
- Delete an Ohai hint file.
:nothing
- Define this resource block to do nothing until notified by another resource to take action. When this resource is notified, the resource block is either run immediately or it is queued up to be run at the end of the Chef Client run.
Properties¶
The ohai_hint resource has the following properties:
compile_time
Ruby Type: true, false | Default Value:
true
Determines whether or not the resource is executed during the compile time phase.
content
Ruby Type: Hash
Values to include in the hint file.
hint_name
Ruby Type: String | Default Value:
'name'
The name of the hints file, if it differs from the resource name.
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.A timer specifies the point during the Chef 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 the Chef 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 thenginx
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 examplenginx
) when a change is detected.A timer specifies the point during the Chef 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 the Chef 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
Examples¶
Create a hint file
ohai_hint 'example' do
content Hash[:a, 'test_content']
end
Create a hint file with a name that does not match the resource name
ohai_hint 'example' do
hint_name 'custom'
end
Create a hint file that is not loaded at compile time
ohai_hint 'example' do
compile_time false
end
Delete a hint file
ohai-hint 'example' do
action :delete
end