Service Template Data

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The following settings can be used during a Chef Habitat service’s lifecycle. This means that you can use these settings in any of the plan hooks, such as init, or run, and also in any templatized configuration file for your application or service.

These configuration settings are referenced using the Handlebars.js version of Mustache-style tags.

sys

System information

Property	Type	Description
ctl_gateway_ip	string	Listening address for Supervisor’s Control Gateway.
ctl_gateway_port	integer	Listening port for Supervisor’s Control Gateway.
gossip_ip	string	Listening address for Supervisor’s gossip connection.
gossip_port	integer	Listening port for Supervisor’s gossip connection.
hostname	string	The hostname of the running service.
http_gateway_ip	string	Listening address for Supervisor’s HTTP gateway.
http_gateway_port	integer	Listening port for Supervisor’s HTTP gateway.
ip	string	The IP address of the running service.
member_id	string	The member’s Supervisor ID, e.g., 3d1e73ff19464a27aea3cdc5c2243f74
permanent	boolean	Set to true if a Supervisor is being used as a permanent peer, to increase Ring network traffic stability.
version	string	Version of the Habitat Supervisor, e.g., 0.54.0/20180221023448

pkg

Details about the package currently running the service

Property	Type	Description
ident	string	The fully-qualified identifier of the running package, e.g., core/redis/3.2.4/20170514150022
origin	string	The origin of the Habitat package
name	string	The name of the Habitat package
version	string	The version of the Habitat package
release	string	The release of the Habitat package
deps	array	An array of runtime dependencies for your package based on the pkg_deps setting in a plan
env	object	The runtime environment of your package, mirroring the contents of the RUNTIME_ENVIRONMENT metadata file. The PATH variable is set, containing all dependencies of your package, as well as any other runtime environment variables that have been set by the package. Individual variables can be accessed directly, like {{pkg.env.PATH}} (the keys are case sensitive).
exposes	array	The array of ports to expose for an application or service. This value is pulled from the pkg_exposes setting in a plan.
exports	object	A map of export key to internal configuration value key (i.e., the contents of pkg_exports in your plan). The key is what external services consume. The value is a key in your default.toml file that corresponds to the data being exported.
path	string	The location where the package is installed locally, e.g., /hab/pkgs/core/redis/3.2.4/20170514150022. Note that this is not a PATH environment variable; for that, please see the env key above.
svc_path	string	The root location of the source files for the Habitat service, e.g., /hab/svc/redis.
svc_config_path	string	The location of any templated configuration files for the Habitat service, e.g., /hab/svc/redis/config.
svc_data_path	string	The location of any data files for the Habitat service, e.g., /hab/svc/redis/data.
svc_files_path	string	The location of any gossiped configuration files for the Habitat service, e.g., /hab/svc/redis/files.
svc_static_path	string	The location of any static content for the Habitat service, e.g., /hab/svc/redis/static.
svc_var_path	string	The location of any variable state data for the Habitat service, e.g., /hab/svc/redis/var.
svc_pid_file	string	The location of the Habitat service pid file, e.g., /hab/svc/redis/PID.
svc_run	string	The location of the rendered run hook for the Habitat service, e.g., /hab/svc/redis/run.
svc_user	string	The value of pkg_svc_user specified in a plan.
svc_group	string	The value of pkg_svc_group specified in a plan.

cfg

These are settings defined in your templatized configuration file. The values for those settings are pulled from the default.toml file included in your package.

svc

Information about the current service’s service group

Property	Type	Description
service	string	The name of the service. If the service is running from the package core/redis, the value will be redis.
group	string	The group portion of the service’s complete group name. In the group name redis.default, the group’s value is default.
org	string	The organization portion of a service group specification. Unused at this time.
election_is_running	boolean	Whether a leader election is currently running for this service
election_is_no_quorum	boolean	Whether there is quorum for a leader election for this service
election_is_finished	boolean	Whether a leader election for this service has finished
update_election_is_running	boolean	Whether an update leader election is currently running for this service
update_election_is_no_quorum	boolean	Whether there is quorum for an update leader election for this service
update_election_is_finished	boolean	Whether an update leader election for this service has finished
me	svc_member	An object that provides information about the service running on the local Supervisor
first	svc_member	The first member of this service group, or the leader, if running in a leader topology
members	array	All active members (alive and suspect) of the service group, across the entire ring. As of 0.56.0, does not include departed or confirmed members
leader	svc_member	The current leader of the service group, if any (null otherwise)
update_leader	svc_member	The current update_leader of the service group, if any (null otherwise)

bind

Exposes information about the service groups this service is bound to. Each key is the name of a bind, while each value is one of the objects described below

Property	Type	Description
first	svc_member	The first member of this service group. If the group is running in a leader topology, this will also be the leader.
leader	svc_member	The current leader of this service group, if running in a leader topology
members	array	All active members (alive and suspect) of the service group, across the entire ring. As of 0.56.0, does not include departed or confirmed members

Reference Objects

Some of the template expressions referenced above return objects of a specific shape; for example, the svc.me and svc.first expressions return “service member” objects, and the pkg property of a service member returns a “package identifier” object. These are defined below.

package_identifier

A Habitat package identifier, split apart into its constituent components

Property	Type	Description
origin	string	The origin of the Habitat package
name	string	The name of the Habitat package
version	string	The version of the Habitat package
release	string	The release of the Habitat package

svc_member

Represents a member of a service group

Property	Type	Description
member_id	string	the member’s Supervisor id, e.g., 3d1e73ff19464a27aea3cdc5c2243f74
alive	boolean	Whether this member is considered alive and connected to the ring, from a network perspective.
suspect	boolean	Whether this member is considered “suspect”, or possibly unreachable, from a network perspective.
confirmed	boolean	Whether this member is confirmed dead / unreachable, from a network perspective.
departed	boolean	Whether this member has been departed from the ring (i.e., permanently gone, never to return).
election_is_running	boolean	Whether a leader election is currently running for this service
election_is_no_quorum	boolean	Whether there is quorum for a leader election for this service
election_is_finished	boolean	Whether a leader election for this service has finished
update_election_is_running	boolean	Whether an update leader election is currently running for this service
update_election_is_no_quorum	boolean	Whether there is quorum for an update leader election for this service
update_election_is_finished	boolean	Whether an update leader election for this service has finished
leader	boolean	Whether this member is the leader in the service group (only meaningful in a leader topology)
follower	boolean	Whether this member is a follower in the service group (only meaningful in a leader topology)
update_leader	boolean	Whether this member is the update leader in the service group (only meaningful in a leader topology)
update_follower	boolean	Whether this member is an update follower in the service group (only meaningful in a leader topology)
pkg	package_identifier	The identifier of the release the member is running
package	string	The package identifier
sys	object	An abbreviated version of the top-level {{sys}} object, containing networking information for the member.
cfg	object	The configuration the member is currently exporting. This is constrained by what is defined in pkg_exports, where the values are replaced with the current values (e.g., taking into account things like user.toml, gossiped configuration values, etc.)
persistent	boolean	A misspelling of permanent; indicates whether a member is a permanent peer or not
service	string	The name of the service. If the service is running from the package core/redis, the value will be redis.
group	string	The group portion of the service’s complete group name. In the group name redis.default, the group’s value is default.
org	string	The organization portion of a service group specification. Unused at this time.