1 # A "migration" is, in technical terms, a plugin whose configuration describes
2 # how to read source data, process it (generally by mapping source fields to
3 # destination fields), and write it to Drupal.
5 # The machine name for a migration, used to uniquely identify it.
8 # A human-friendly description of the migration.
9 label: Migrate style categories from the source database to taxonomy terms
11 # The machine name of the group containing this migration (which contains shared
12 # configuration to be merged with our own configuration here).
15 # Every migration must have a source plugin, which controls the delivery of our
16 # source data. In this case, our source plugin has the name "beer_term", which
17 # Drupal resolves to the PHP class defined in
18 # src/Plugin/migrate/source/BeerTerm.php.
22 # Every migration must also have a destination plugin, which handles writing
23 # the migrated data in the appropriate form for that particular kind of data.
24 # Most Drupal content is an "entity" of one type or another, and we need to
25 # specify what entity type we are populating (in this case, taxonomy terms).
26 # Unlike the source plugin (which is specific to our particular scenario), this
27 # destination plugin is implemented in Drupal itself.
29 plugin: entity:taxonomy_term
31 # Here's the meat of the migration - the processing pipeline. This describes how
32 # each destination field is to be populated based on the source data. For each
33 # destination field, one or more process plugins may be invoked.
35 # The simplest process plugin is named 'get' - it is the default plugin, so
36 # does not need to be explicitly named. It simply copies the source value
37 # (the 'style' field from the source database in this case) to the destination
38 # field (the taxonomy term 'name' field). You can see we simply copy the
39 # source 'details' field to destination 'description' field in the same way.
43 # Here is a new plugin - default_value. In its simplest usage here, it is used
44 # to hard-code a destination value, the vid (vocabulary ID) our taxonomy terms
45 # should be assigned to. It's important to note that while above the right
46 # side of the mappings was a source field name, here the right side of the
47 # 'default_value:' line is an actual value.
50 default_value: migrate_example_beer_styles
52 # Here's another new plugin - migration. When importing data from another
53 # system, typically the unique identifiers for items on the destination side
54 # are not the same as the identifiers were on the source side. For example, in
55 # our style data the term names are the unique identifiers for each term,
56 # while in Drupal each term is assigned a unique integer term ID (tid). When
57 # any such items are referenced in Drupal, the reference needs to be
58 # translated from the old ID ('ale') to the new ID (1). The migration
59 # framework keeps track of the relationships between source and destination
60 # IDs in map tables, and the migration plugin is the means of performing a
61 # lookup in those map tables during processing.
64 # Here we reference the migration whose map table we're performing a lookup
65 # against. You'll note that in this case we're actually referencing this
66 # migration itself, since category parents are imported by the same
67 # migration. This works best when we're sure the parents are imported
68 # before the children, and in this case our source plugin is guaranteeing
71 # 'style_parent' is the parent reference field from the source data. The
72 # result of this plugin is that the destination 'parent' field is populated
73 # with the Drupal term ID of the referenced style (or NULL if style_parent
77 # We'll learn more about dependencies in beer_node - here, we leave them empty.
78 migration_dependencies: {}
80 # By default, configuration entities (like this migration) are not automatically
81 # removed when the migration which installed them is uninstalled. To have your
82 # migrations uninstalled with your migration module, add an enforced dependency