Added orcid field to ArticleDocument

Utilized the same method used on the legacy article serializer in order to obtain the orcid and add it to the ArticleDocument.

scoap3/articles/documents.py

@@ -3,7 +3,7 @@
 from django_opensearch_dsl.registries import registry
 
 from scoap3.articles.models import Article, ArticleFile, ArticleIdentifier
-from scoap3.authors.models import Author
+from scoap3.authors.models import Author, AuthorIdentifierType
 from scoap3.misc.models import Affiliation, ArticleArxivCategory, PublicationInfo
 
 
@@ -143,6 +143,19 @@ def prepare_authors(self, instance):
                 "first_name": author.first_name.strip(),
                 "last_name": author.last_name.strip(),
                 "affiliations": serialized_affiliations,
+                **(
+                        {
+                            "orcid": author.identifiers.filter(
+                                identifier_type=AuthorIdentifierType.ORCID
+                            )
+                            .values_list("identifier_value", flat=True)
+                            .first()
+                        }
+                        if author.identifiers.filter(
+                            identifier_type=AuthorIdentifierType.ORCID
+                        ).exists()
+                        else {}
+                ),
             }
             serialized_authors.append(serialized_author)
         return serialized_authors