Same name and namespace in other branches
- 8.9.x core/modules/migrate/src/Plugin/migrate/process/Flatten.php \Drupal\migrate\Plugin\migrate\process\Flatten
- 9 core/modules/migrate/src/Plugin/migrate/process/Flatten.php \Drupal\migrate\Plugin\migrate\process\Flatten
Flattens the source value.
The flatten process plugin converts a nested array into a flat array. For example [[1, 2, [3, 4]], [5], 6] becomes [1, 2, 3, 4, 5, 6]. During some types of processing (e.g. user permission splitting), what was once a one-dimensional array gets transformed into a multidimensional array. This plugin will flatten them back down to one-dimensional arrays again.
Example:
process:
tags:
-
plugin: default_value
source: foo
default_value: [bar, [alpha, beta]]
-
plugin: flatten
In this example, the default_value process returns [bar, [alpha, beta]] (given a NULL value of foo). At this point, Migrate would try to import two items: bar and [alpha, beta]. The latter is not a valid one and won't be imported. We need to pass the values through the flatten processor to obtain a three items array [bar, alpha, beta], suitable for import.
Plugin annotation
@MigrateProcessPlugin(
id = "flatten",
handle_multiples = TRUE
)
Hierarchy
- class \Drupal\migrate\Plugin\migrate\process\Flatten extends \Drupal\migrate\ProcessPluginBase
Expanded class hierarchy of Flatten
See also
\Drupal\migrate\Plugin\MigrateProcessInterface
1 file declares its use of Flatten
- FlattenTest.php in core/
modules/ migrate/ tests/ src/ Unit/ process/ FlattenTest.php
File
- core/
modules/ migrate/ src/ Plugin/ migrate/ process/ Flatten.php, line 45
Namespace
Drupal\migrate\Plugin\migrate\processView source
class Flatten extends ProcessPluginBase {
/**
* Flatten nested array values to single array values.
*
* For example, [[1, 2, [3, 4]]] becomes [1, 2, 3, 4].
*/
public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
if (!is_array($value) && !is_object($value)) {
$type = gettype($value);
throw new MigrateException(sprintf("Input should be an array or an object, instead it was of type '%s'", $type));
}
return iterator_to_array(new \RecursiveIteratorIterator(new \RecursiveArrayIterator($value)), FALSE);
}
}
Members
Name | Modifiers | Type | Description | Overrides |
---|---|---|---|---|
Flatten:: |
public | function | Flatten nested array values to single array values. |