Following years of hard work to convert all Drupal 7 style variables to the Drupal 8 configuration system and state systems, the variable_get()/variable_set() and variable_del() API is now fully removed. The variable subsystem was in place for so long to support settings not yet converted to the new configuration system but that process is now complete. The old variable_* API was removed in favor of two new systems. You should review the Overview of Configuration (vs. other types of information) to determine what system is the best successor for your Drupal 7 variable.
State system
If the data you used to tuck into variable_* is derived from other data and/or temporary in nature, you should use the State API to store it.
Configuration system
To learn more about the new configuration API, see the Configuration API in Drupal 8 section of the Drupal 8 API documentation. See the basics for getting/setting/removing configuration values on the Simple configuration API page.
This change removed
- The
DRUPAL_BOOTSTRAP_VARIABLES
bootstrap phase variable_initialize()
variable_get()
variable_set()
variable_del()
- The
$new_phase
parameter ofdrupal_bootstrap()
- The {variable} database table
_drupal_bootstrap_variables()