Migrating Datetime Stamps with Migrate Plus

A quick snippet on migrating other formats of datetime strings into Drupal 8:

created:
  plugin: format_date
  from_format: 'Y-m-d\TH:i:s+'
  to_format: 'U'
  timezone: 'America/Los_Angeles'
  settings:
    validate_format: false
  source: created
changed:
  plugin: format_date
  from_format: 'Y-m-d\TH:i:s+'
  to_format: 'U'
  timezone: 'America/Los_Angeles'
  settings:
    validate_format: false
  source: updated

This will bring in values for node creation and last update (assuming source fields defined as “created” and “updated”) using the format_date plugin. The example snippets in Drupal’s documentation are based largely around having date fields as the target of migration, which will take a format such as ‘Y-m-d\TH:i:s’, whereas the created/changed values want a unix epoch string, as denoted with ‘U’.