Make Some operations Programmatically - Hook Update Deploy Tools

Hook Update Deploy Tools is a great contrib module help to make most of site deploy operations programmatically.

Link : https://www.drupal.org/project/hook_update_deploy_tools

CAUTION : Current drupal 8 version is unstable (8.x-1.0-unstable1, 2016-Feb-07 Version),  but 8.x-1.x-dev version is usable.

Example: Delete a field instance.

Using contrib module hook_update_deploy_tools

//Drupal 8:

$message = \HookUpdateDeployTools\Fields::deleteInstance('taxonomy_term', 'field_name', 'tags');

//Drupal 7:  

$message = HookUpdateDeployTools\Fields::deleteInstance('taxonomy_term', 'field_name', 'tags');

Without Hook Update Deploy Tools

//Drupal 8:

//Drupal 7:

$instance = field_info_instance('node', 'field_name', 'page');//For node

$instance = field_info_instance('taxonomy_term', 'field_name', 'tags');//For taxonomy term

if ($instance) {

  field_delete_instance($instance);

}

//D8 (Not tested)

$field_info = \Drupal\field\Entity\FieldConfig::loadByName('node', 'page', 'field_name');

$field_info->delete();