GetChannel returns the TELEPORT_AUTOMATIC_UPGRADES_CHANNEL value.

GetUpgraderVersion returns the teleport upgrader version.

IsEnabled reads the TELEPORT_AUTOMATIC_UPGRADES and returns whether Automatic Upgrades are enabled or disabled.

NewDefaultChannel creates a default automatic upgrade channel It looks up the TELEPORT_AUTOMATIC_UPGRADES_CHANNEL environment variable for backward compatibility, and if not found uses binary version.

EnvUpgrader environment variable specifies the external upgrader type Ex: unit, kube.

EnvUpgraderVersion environment variable specifies the external upgrader version Ex: v14.3.6.

Channel describes an automatic update channel configuration.

Channels is a map of Channel objects.