Allow migration of custom link types

[pixelmachine]

I've just migrated from Typed Link and most of the fields are good but there are a few errors like:

Preparing to migrate field “callToAction” (2f63b7f2-25ba-4846-9c47-296399a68370) content.
    > Unable to convert content #52992 for element #89509
    > Unable to convert content #53000 for element #89780
    > Unable to convert content #53002 for element #89792
    > Unable to convert content #53003 for element #89798
    > Field “callToAction” content migrated.

[pixelmachine]

All of the failures are custom link types and I see now that the migration only targets the built in types. Perhaps it would be good to have a way to pass additional classes to the migration?

For example just passing the relevant class into the $typeMap works perfectly and imports custom links:

MigrateTypedLinkField.php
MigrateTypedLinkContent.php

public array $typeMap = [
  // ... (default link types) ...
  // My custom link type
  'book' => \modules\booklink\models\BookLinkType::class,
]

[engram-design]

So yep, there's no handling for custom link types as you'd need to provide a source and destination class to convert them to. But you can of course use an event to register your own handling of these custom types. See docs

This will modify the typeMap property to translate what the old link type was to the new one. Yours would look something like:

use verbb\hyper\events\ModifyMigrationLinkEvent;
use verbb\hyper\migrations\MigrateTypedLinkField;
use verbb\hyper\migrations\MigrateTypedLinkContent;
use yii\base\Event;

Event::on(MigrateTypedLinkField::class, MigrateTypedLinkField::EVENT_MODIFY_LINK_TYPE, function(ModifyMigrationLinkEvent $event) {
    if ($event->oldClass === 'book') {
        $event->newClass = \modules\booklink\models\BookLinkType::class;
    }
});

Event::on(MigrateTypedLinkContent::class, MigrateTypedLinkContent::EVENT_MODIFY_LINK_TYPE, function(ModifyMigrationLinkEvent $event) {
    if ($event->oldClass === 'book') {
        $event->newClass = \modules\booklink\models\BookLinkType::class;
    }
});

[pixelmachine]

Ah lovely, thanks Josh! It's right in the docs for exactly this and I missed it 🫣