I need help migrating a mulit-value link field from string w/ 2 delimiters

Question

I'm trying to migrate a node bundle from one drupal 9 application to another.

My source format is an XML document.

I'm stuck migrating a multi-value link field.

Both the source and destination machine names are field_quicklinks.

The source value is a string with two delimiters like the following.

"https://www.somedomain.org/somewhere/something.pdf*Something Document^https://www.someotherdomain.org/somewhere-else/some-other-document.pdf*Some Other Document^https://www.yetsomeotherdomain.org/yet-somewhere-else/yet-another-document.pdf*Yet Another Document"

So my intent is to explode this twice to look like:

[
  [
    "https://www.somedomain.org/somewhere/something.pdf",
    "Something Document"
  ],
  [
    "https://www.someotherdomain.org/somewhere-else/some-other-document.pdf",
    "Some Other Document"
  ],
  [
    "https://www.yetsomeotherdomain.org/yet-somewhere-else/yet-another-document.pdf",
    "Yet Another Document"
  ]
]

The latest iteration of my attmpts looks like:

field_quicklinks:
    -
      plugin: skip_on_value
      method: process
      value: FIELD_EMPTY
      source: field_quicklinks
    -
      plugin: explode
      source: field_quicklinks
      delimiter: '^'
    -
      plugin: multiple_values
      source: field_quicklinks
    -
      plugin: explode
      source: field_quicklinks
      delimiter: '*'
    -
      plugin: sub_process
      source: field_quicklinks
        process:
          field_quicklinks/uri:
              plugin: callback
              source: field_quicklinks
              callable: array_shift
    -
      plugin: sub_process
      source: field_quicklinks
      process:
        field_quicklinks/title:
            plugin: callback
            source: field_quicklinks
            callable: array_pop

If somebody could get me on track I would of course appreciate it very much.

Answer 1

So I'm betting there's an existing way to accomplish this but I was spending way too much time on it and decided to create a custom process plugin.

The relevant part of my migration yaml looks like:

field_quicklinks_array:
    -
      plugin: skip_on_value
      method: process
      value: FIELD_EMPTY
      source: field_quicklinks
    -
      plugin: str_with_two_delimiters
field_quicklinks:
    plugin: sub_process
    source: '@field_quicklinks_array'
    process:
      uri: uri
      title: title

My custom process plugin which I placed here:

web/modules/custom/my_bundle_migration/src/Plugin/migrate/process/ParseStringWithTwoDelimiters.php

looks like:

<?php

  namespace Drupal\my_bundle_migration\Plugin\migrate\process;

  use Drupal\migrate\ProcessPluginBase;
  use Drupal\migrate\MigrateException;
  use Drupal\migrate\MigrateExecutableInterface;
  use Drupal\migrate\Row;
  /**
   * This plugin converts a string with two delimiters into an array of arrays
   *
   * @MigrateProcessPlugin(
   *   id = "str_with_two_delimiters"
   * )
   */
   class ParseStringWithTwoDelimiters extends ProcessPluginBase {
     /**
      * {@inheritdoc}
      */
      public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
        $prelim_results_array = [];
        $final_results_array = [];
        $array_one = explode("^",$value);
        foreach ($array_one as $element) {
          array_push($prelim_results_array,explode("*",$element));
        }
        foreach($prelim_results_array as $v){
          array_push($final_results_array,['uri' => $v[0], 'title' => $v[1]]);
        }

        return $final_results_array;

      }

   }