How can I redirect from a non-locale url to a specific locale

Question

When moving an existing multilanguage site (Jive CMS) to Drupal we need to redirect URLs like /docs/DOC-1763 to the German version of a node. They are a lot, so we need a migration for it.

We're using the Redirect module, but when setting the language to German it only works for /de/docs/DOC-1763, which is of course not what is needed.

How can we redirect old root URLs like /docs/DOC-1763 to the new German version of this content? The URL would be /de/something/different for the node whose ID is 5, for example.

Answer 1

So it turns out, this is kind of a long known gab in the redirect module.

For us it worked with patch #42 in the redirect module (using cweagans/composer-patches composer library) and then importing the redirects using migration. This is what worked for us (massive thx to this example):

id: custom_redirects
label: 'Import DE urls as redirects to the node'
source:
  plugin: url
  data_fetcher_plugin: file
  data_parser_plugin: json
  # ... and the mapping, I spare you the details
  constants:
    status_code: 301
    redirect_prefix: 'internal:/de/node/'

process:
  temp_nid:
    plugin: migration_lookup
    source: jiveid
    migration: custom_contents
  language:
    plugin: default_value
    default_value: und
  redirect_source:
    - plugin: substr
      source: url/de
      start: 1
  redirect_redirect:
    plugin: concat
    source:
      - constants/redirect_prefix
      - "@temp_nid"
  status_code: constants/status_code

destination:
  plugin: entity:redirect

migration_dependencies:
  required:
    - custom_contents

So with our example above this would end up with values:

process:
  language: 'und'
  redirect_source: 'docs/DOC-1763'
  redirect_redirect: 'internal:/de/node/5'
  status_code: 301

The migrate module (don't forget the patch) does then the rest and redirects correctly from /docs/DOC-1763 to /de/something/different.