Problem/Motivation
When I run
drush migrate:import upgrade_d7_field_instance --migrate-debug
upgrade_d7_field_instance yml is generated by migrate upgrade without any modification,
I have the following errors:
In DiscoveryTrait.php line 53:
The "" plugin does not exist. Valid plugin IDs for Drupal\migrate\Plugin\Mi
gratePluginManager are: addressfield, block_plugin_id, block_region, block_
settings, block_theme, block_visibility, field_type, process_field, field_f
ormatter_settings_defaults, d6_field_instance_defaults, d6_field_instance_o
ption_translation, d6_field_field_settings, field_instance_widget_settings,
d6_field_option_translation, field_settings, d6_field_type_defaults, field
_bundle, d7_field_instance_defaults, d7_field_instance_option_translation,
d7_field_instance_settings, d7_field_option_translation, d7_field_settings,
d7_field_type_defaults, d7_field_permission_settings, d6_field_file, file_
uri, filter_id, filter_settings, filter_format_permission, geofield_d7d8, g
eofield_field_settings, geofield_latlon, geofield_wkt, google_analytics_vis
ibility_pages, google_analytics_visibility_roles, d6_imagecache_actions, in
line_entity_form_field_instance_settings, field_link, link_options, link_ur
i, d6_nodewords_entities, d7_metatag_entities, array_build, callback, conca
t, default_value, download, entity_exists, explode, extract, file_copy, fla
tten, format_date, get, log, machine_name, make_unique_entity_field, menu_l
ink_parent, migration_lookup, null_coalesce, route, skip_on_empty, skip_row
_if_not_set, static_map, sub_process, substr, urlencode, debug, node_comple
te_node_lookup, node_complete_node_revision_lookup, node_complete_node_tran
slation_lookup, array_pop, array_shift, default_entity_value, dom, dom_appl
y_styles, dom_migration_lookup, dom_remove, dom_select, dom_str_replace, en
tity_generate, entity_lookup, entity_value, file_blob, gate, merge, multipl
e_values, service, single_value, skip_on_value, str_replace, transliteratio
n, transpose, node_update_7008, path_set_translated, d6_url_alias_language,
d6_path_redirect, d7_path_redirect, d7_redirect_source_query, search_confi
guration_rankings, system_update_7000, timezone, forum_vocabulary, convert_
tokens, profile_field_settings, user_langcode, user_update_8002, d6_profile
_field_option_translation, user_update_7002, field_collection_field_instanc
e_settings, field_collection_field_settings, paragraphs_field_instance_sett
ings, paragraphs_field_settings, paragraphs_lookup, paragraphs_process_on_v
alue
Steps to reproduce
There can be various reasons like core or contrib module bugs or migration misconfigurations causing this error message.
The problem is, that the error message is useless as it contains no helpful information WHAT went wrong WHERE.
Proposed resolution
Add more details to the error message, so the message is helpful and allows finding the root cause of the error.
Remaining tasks
User interface changes
None
API changes
None
Data model changes
None
Release notes snippet
Provide more details on 'The "" plugin does not exist' Migration error messages.