Figure out a way to get a list of fields for a content type via REST

[mjordan]

If we can inspect the fields that a content type has configured, we can validate that the columns in the input file match machine field names, and we can also dynamically create requests for string, taxo term, and linked references.

[mjordan]

Unfortunately, curl -v "admin:islandora@localhost:8000/entity/node_type/islandora_object" doesn't return a list of fields:

{"uuid":"c720394c-5f28-4290-be53-88bc7de9c7bc","langcode":"en","status":true,"dependencies":{"enforced":{"module":["islandora_defaults"]},"module":["menu_ui"]},"third_party_settings":{"menu_ui":{"available_menus":["main"],"parent":"main:"}},"name":"Repository Item","type":"islandora_object","description":"An item in your Islandora repository.","help":"","new_revision":true,"preview_mode":1,"display_submitted":true}

JSON::API also provides a way to GET config entities, and provides this example:

curl \ --header 'Accept: application/vnd.api+json' \ http://admin:admin@drupal.d8/jsonapi/menu/menu

Can't find any documentation though.

[mjordan]

JSON::API to the rescue:

curl --header 'Accept: application/vnd.api+json' -o test2.json http://admin:islandora@localhost:8000/jsonapi/node/islandora_object?page[limit]=1

will return one node of the islandora_object type, with all fields listed and populated. Doesn't give you the field type or UUID, though.

[mjordan]

JSON::API allows fetching of field configuration by field UUID:

http://localhost:8000/jsonapi/field_config/field_config/8d5c9dc2-1823-43c9-8c6f-5fae6ae77ec4

So, if we can get field UUIDs from content types, we can introspect a node's fields prior to generating requests. Only missing piece is to get the field UUIDs on a node.

[mjordan]

http://admin:islandora@localhost:8000/jsonapi/field_config/field_config provides all the fields and their configuration info.

#!/usr/bin/env python3

import os
import sys
import json
import requests

fields_url = 'http://admin:islandora@localhost:8000/jsonapi/field_config/field_config'

headers = {'Content-Type': 'application/json'}
response = requests.get(fields_url, auth=('admin', 'islandora'), headers=headers)

field_config = json.loads(response.text)
field_types = {}
for item in field_config['data']:
	field_name = item['attributes']['field_name']
	field_types[field_name] = item['attributes']['field_type']

print(field_types)

gets us a dictionary like this:

{
'body': 'text_with_summary',
'comment_body': 'text_long',
'field_access_terms': 'entity_reference',
'field_file_size': 'integer', 
'field_media_audio_file': 'file',
'field_media_of': 'entity_reference',
'field_media_use': 'entity_reference',
'field_mime_type': 'string',
'field_media_file': 'file',
'field_height': 'integer',
'field_media_image': 'image',
'field_width': 'integer',
'field_media_oembed_video': 'string',
'field_media_video_file': 'file',
'comment': 'comment',
'field_image': 'image',
'field_tags': 'entity_reference',
'field_alternative_title': 'string',
'field_description': 'string_long',
'field_display_hints': 'entity_reference',
'field_edtf_date': 'edtf',
'field_edtf_date_created': 'edtf',
'field_edtf_date_issued': 'edtf',
'field_extent': 'string',
'field_identifier': 'string',
'field_linked_agent': 'typed_relation',
'field_member_of': 'entity_reference',
'field_model': 'entity_reference',
'field_pid': 'string',
'field_resource_type': 'entity_reference',
'field_rights': 'string',
'field_subject': 'entity_reference'
}

[mjordan]

A glitch. Neither /jsonapi/field_config/field_config/8d5c9dc2-1823-43c9-8c6f-5fae6ae77ec4 nor /jsonapi/field_config/field_config provides the cardinality of a field. This is important since PATCHing replaces all values in a field. If a multivalued field already has a value, and we want to keep it and add a second value, we need to get the original value and include it in our PATCH. If a field is monovalued, we can only include one value in our PATCH.

[mjordan]

http://admin:islandora@localhost:8000/jsonapi/field_storage_config/field_storage_config provides cardinality.

[mjordan]

Resolved with 3e95222.