Updated Drupal to 8.6. This goes with the following updates because it's possible...
[yaffs-website] / web / core / modules / path / migrations / d6_url_alias.yml
1 id: d6_url_alias
2 label: URL aliases
3 migration_tags:
4   - Drupal 6
5   - Content
6 source:
7   plugin: d6_url_alias
8   constants:
9     slash: '/'
10 process:
11   source:
12     plugin: concat
13     source:
14       - constants/slash
15       - src
16   alias:
17     plugin: concat
18     source:
19       - constants/slash
20       - dst
21   langcode:
22     plugin: d6_url_alias_language
23     source: language
24   node_translation:
25     -
26       plugin: explode
27       source: src
28       delimiter: /
29     -
30       # If the source path has no slashes return a dummy default value.
31       plugin: extract
32       default: 'INVALID_NID'
33       index:
34         - 1
35     -
36       plugin: migration_lookup
37       migration: d6_node_translation
38 destination:
39   plugin: url_alias