Bug 35197: Add additional_fields REST API endpoint

Test plan:
1) Apply patch, restart plack 'koha-plack --restart kohadev'
2) Visit /api/v1/additional_fields?tablename=aqinvoices - Notice its empty
3) Visit /cgi-bin/koha/admin/additional-fields.pl?tablename=aqbasket and add a new additional field
4) Do step 2) again - Notice the newly created additional field is there
5) Visit /cgi-bin/koha/admin/additional-fields.pl?tablename=aqinvoices and add a new additional field for invoices
6) Do step 2) again - Notice both additional fields are there
7) Visit /api/v1/additional_fields?tablename=aqinvoices - Notice only the additional field for aqinvoices is listed

Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>

Koha/REST/V1/AdditionalFields.pm

@@ -0,0 +1,52 @@
+package Koha::REST::V1::AdditionalFields;
+
+# This file is part of Koha.
+#
+# Koha is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# Koha is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Koha; if not, see <http://www.gnu.org/licenses>.
+
+use Modern::Perl;
+
+use Mojo::Base 'Mojolicious::Controller';
+
+use Koha::AdditionalFields;
+
+use Try::Tiny qw( catch try );
+
+=head1 API
+
+=head2 Methods
+
+=head3 list
+
+=cut
+
+sub list {
+    my $c = shift->openapi->valid_input or return;
+
+    my $tablename = $c->param('tablename');
+
+    return try {
+        my $additional_fields_set = Koha::AdditionalFields->new;
+        if ($tablename) {
+            $additional_fields_set = $additional_fields_set->search( { tablename => $tablename } );
+        }
+        my $additional_fields = $c->objects->search($additional_fields_set);
+        return $c->render( status => 200, openapi => $additional_fields );
+    } catch {
+        $c->unhandled_exception($_);
+    };
+
+}
+
+1;

api/v1/swagger/definitions/additional_field.yaml

@@ -0,0 +1,35 @@
+---
+type: object
+properties:
+  id:
+    type: integer
+    description: internally assigned additional field identifier
+    readOnly: true
+  tablename:
+    description: name of the table this additional field corresponds to
+    type: string
+  name:
+    description: name of the additional field
+    type: string
+  authorised_value_category:
+    description: authorised value category of the additional field
+    type:
+      - string
+      - "null"
+  marcfield:
+    description: marcfield of the additional field
+    type: string
+  marcfield_mode:
+    description: marcfield mode of the additional field
+    type: string
+    enum:
+      - get
+      - set
+  searchable:
+    description: is the additional field searchable
+    type: boolean
+
+additionalProperties: false
+required:
+  - id
+  - tablename

api/v1/swagger/paths/additional_fields.yaml

@@ -0,0 +1,49 @@
+---
+/additional_fields:
+  get:
+    x-mojo-to: AdditionalFields#list
+    operationId: listAdditionalFields
+    tags:
+      - additional_fields
+    summary: List additional fields
+    produces:
+      - application/json
+    parameters:
+      - description: filter by table name
+        in: query
+        name: tablename
+        type: string
+      - $ref: "../swagger.yaml#/parameters/match"
+      - $ref: "../swagger.yaml#/parameters/order_by"
+      - $ref: "../swagger.yaml#/parameters/page"
+      - $ref: "../swagger.yaml#/parameters/per_page"
+      - $ref: "../swagger.yaml#/parameters/q_param"
+      - $ref: "../swagger.yaml#/parameters/q_body"
+    responses:
+      200:
+        description: A list of additional_fields
+        schema:
+          items:
+            $ref: "../swagger.yaml#/definitions/additional_field"
+          type: array
+      400:
+        description: Bad request
+        schema:
+          $ref: "../swagger.yaml#/definitions/error"
+      403:
+        description: Access forbidden
+        schema:
+          $ref: "../swagger.yaml#/definitions/error"
+      500:
+        description: |-
+          Internal server error. Possible `error_code` attribute values:
+          * `internal_server_error`
+        schema:
+          $ref: "../swagger.yaml#/definitions/error"
+      503:
+        description: Under maintenance
+        schema:
+          $ref: "../swagger.yaml#/definitions/error"
+    x-koha-authorization:
+      permissions:
+        tools: manage_additional_fields

api/v1/swagger/swagger.yaml

@@ -4,6 +4,8 @@ basePath: /api/v1
 definitions:
   account_line:
     $ref: ./definitions/account_line.yaml
+  additional_field:
+    $ref: ./definitions/additional_field.yaml
   advancededitormacro:
     $ref: ./definitions/advancededitormacro.yaml
   allows_renewal:
@@ -197,6 +199,8 @@ paths:
     $ref: "./paths/acquisitions_vendors.yaml#/~1acquisitions~1vendors~1{vendor_id}"
   "/acquisitions/vendors/{vendor_id}/issues":
     $ref: "./paths/acquisitions_vendor_issues.yaml#/~1acquisitions~1vendors~1{vendor_id}~1issues"
+  /additional_fields:
+    $ref: ./paths/additional_fields.yaml#/~1additional_fields
   /advanced_editor/macros:
     $ref: ./paths/advancededitormacros.yaml#/~1advanced_editor~1macros
   /advanced_editor/macros/shared: