search_api_solr.routing.yml

search_api_solr.solr_config_form:
  path: '/admin/config/search/search-api/server/{search_api_server}/files'
  options:
    parameters:
      search_api_server:
        type: entity:search_api_server
  defaults:
    _form: '\Drupal\search_api_solr\Form\SolrConfigForm'
  requirements:
    _permission: 'administer search_api'
    _custom_access: '\Drupal\search_api_solr\Form\SolrConfigForm::access'