habitat_service Resource
This page is generated from the Chef Infra Client source code.To suggest a change, edit the habitat_service.rb file and submit a pull request to the Chef Infra Client repository.
Use the habitat_service resource to manage Chef Habitat services. This requires that core/hab-sup
be running as a service. See the habitat_sup
resource documentation for more information.
Note
Applications may run as a specific user. Often with Habitat, the default is hab
, or root
. If the application requires another user, then it should be created with Chef’s user
resource.
New in Chef Infra Client 17.3.
Syntax
The full syntax for all of the properties that are available to the habitat_service resource is:
habitat_service 'name' do
bind String, Array # default value: []
binding_mode Symbol, String # default value: :strict
bldr_url String # default value: "https://bldr.habitat.sh/"
channel Symbol, String # default value: :stable
gateway_auth_token String
health_check_interval Integer # default value: 30
remote_sup String # default value: "127.0.0.1:9632"
remote_sup_http String # default value: "127.0.0.1:9631"
service_group String # default value: "default"
service_name String # default value: 'name' unless specified
shutdown_timeout Integer # default value: 8
strategy Symbol, String # default value: :none
topology Symbol, String # default value: :standalone
update_condition Symbol, String # default value: :latest
action Symbol # defaults to :load if not specified
end
where:
habitat_service
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.bind
,binding_mode
,bldr_url
,channel
,gateway_auth_token
,health_check_interval
,remote_sup
,remote_sup_http
,service_group
,service_name
,shutdown_timeout
,strategy
,topology
, andupdate_condition
are the properties available to this resource.
Actions
The habitat_service resource has the following actions:
:load
- (default action) runs
hab service load
to load and start the specified application service (default) :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.
:reload
- runs the
:unload
and then:load
actions :restart
- runs the
:stop
and then:start
actions :start
- runs
hab service start
to start the specified application service :stop
- runs
hab service stop
to stop the specified application service :unload
- runs
hab service unload
to unload and stop the specified application service
Properties
The habitat_service resource has the following properties:
bind
- Ruby Type: String, Array | Default Value:
[]
Passes
--bind
with the specified services to bind to the hab command. If an array of multiple service binds are specified then a--bind
flag is added for each.
binding_mode
- Ruby Type: Symbol, String | Default Value:
:strict
Allowed Values::strict, "strict", :relaxed, "relaxed"
Passes
--binding-mode
with the specified binding mode. Defaults to:strict
. Options are:strict
or:relaxed
bldr_url
- Ruby Type: String | Default Value:
https://bldr.habitat.sh/
Passes
--url
with the specified Habitat Builder URL to the hab command. Depending on the type of Habitat Builder you are connecting to, this URL will look different, here are the 3 current types: - Public Habitat Builder (default) -https://bldr.habitat.sh
- On-Prem Habitat Builder installed using the Source Install Method -https://your.bldr.url
- On-Prem Habitat Builder installed using the Automate Installer -https://your.bldr.url/bldr/v1
channel
- Ruby Type: Symbol, String | Default Value:
:stable
Passes
--channel
with the specified channel to the hab command
gateway_auth_token
- Ruby Type: String
Auth token for accessing the remote supervisor’s http port.
health_check_interval
- Ruby Type: Integer | Default Value:
30
The interval (seconds) on which to run health checks.
remote_sup
- Ruby Type: String | Default Value:
127.0.0.1:9632
Address to a remote Supervisor’s Control Gateway
remote_sup_http
- Ruby Type: String | Default Value:
127.0.0.1:9631
IP address and port used to communicate with the remote supervisor. If this value is invalid, the resource will update the supervisor configuration each time Chef Infra Server runs.
service_group
- Ruby Type: String | Default Value:
default
Passes
--group
with the specified service group to the hab command
service_name
- Ruby Type: String | Default Value:
The resource block's name
The name of the service, must be in the form of
origin/name
shutdown_timeout
- Ruby Type: Integer | Default Value:
8
The timeout in seconds allowed during shutdown.
strategy
- Ruby Type: Symbol, String | Default Value:
:none
Allowed Values::none, "none", :"at-once", "at-once", :rolling, "rolling"
Passes
--strategy
with the specified update strategy to the hab command. Defaults to:none
. Other options are:'at-once'
and:rolling
topology
- Ruby Type: Symbol, String | Default Value:
:standalone
Allowed Values::standalone, "standalone", :leader, "leader"
Passes
--topology
with the specified service topology to the hab command
update_condition
- Ruby Type: Symbol, String | Default Value:
:latest
Allowed Values::latest, "latest", :"track-channel", "track-channel"
Passes
--update-condition
dictating when this service should updated. Defaults tolatest
. Options arelatest
ortrack-channel
**_Note
This requires a minimum habitat version of 1.5.71_** -
latest
: Runs the latest package that can be found in the configured channel and local packages. -track-channel
: Always run the package at the head of a given channel. This enables service rollback, where demoting a package from a channel will cause the package to rollback to an older version of the package. A ramification of enabling this condition is that packages that are newer than the package at the head of the channel are also uninstalled during a service rollback.
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 habitat_service resource in recipes:
Install and load nginx
habitat_package 'core/nginx'
habitat_service 'core/nginx'
habitat_service 'core/nginx unload' do
service_name 'core/nginx'
action :unload
end
Pass the strategy
and topology
options to hab service commands
habitat_service 'core/redis' do
strategy 'rolling'
topology 'standalone'
end
Using update_condition
habitat_service 'core/redis' do
strategy 'rolling'
update_condition 'track-channel'
topology 'standalone'
end
If the service has it’s own user specified that is not the hab
user, don’t create the hab
user on install, and instead create the application user with Chef’s user
resource
habitat_install 'install habitat' do
create_user false
end
user 'acme-apps' do
system true
end
habitat_service 'acme/apps'