migrate_file_to_media-8.x-1.x-dev/migrate_file_to_media_d7_d8/config/install/migrate_plus.migration.mig_article_media_step2.yml

# This migration links the newly created media entities with entity reference field on the target bundle.

id: mig_article_media_step2
label: Article Media Mapping

source:
    key: migration_source_db

    plugin: d7_node
    node_type: article

destination:
    plugin: entity:node

process:
    nid: nid
    changed: changed

    field_media:
        plugin: file_id_lookup
        source: field_image
        migration: mig_article_media_step1
        no_stub: true

migration_dependencies:
    optional:
        - mig_article_node
        - mig_article_media_step1