fix: make meta produced by DOCXToDocument JSON serializable (#8263)

* make meta from DOCXToDocument JSON serializable

* unused import

* update docstrings

haystack/components/converters/docx.py

@@ -4,7 +4,6 @@
 
 import io
 from dataclasses import dataclass
-from datetime import datetime
 from pathlib import Path
 from typing import Any, Dict, List, Optional, Union
 
@@ -30,13 +29,13 @@ class DOCXMetadata:
     :param category: The category
     :param comments: The comments
     :param content_status: The content status
-    :param created: The creation date
+    :param created: The creation date (ISO formatted string)
     :param identifier: The identifier
     :param keywords: Available keywords
     :param language: The language of the document
-    :param last_modified_by: The last modified by user date
-    :param last_printed: The last printed date
-    :param modified: The last modification date
+    :param last_modified_by: User who last modified the document
+    :param last_printed: The last printed date (ISO formatted string)
+    :param modified: The last modification date (ISO formatted string)
     :param revision: The revision number
     :param subject: The subject
     :param title: The title
@@ -47,13 +46,13 @@ class DOCXMetadata:
     category: str
     comments: str
     content_status: str
-    created: Optional[datetime]
+    created: Optional[str]
     identifier: str
     keywords: str
     language: str
     last_modified_by: str
-    last_printed: Optional[datetime]
-    modified: Optional[datetime]
+    last_printed: Optional[str]
+    modified: Optional[str]
     revision: int
     subject: str
     title: str
@@ -192,13 +191,15 @@ class DOCXToDocument:
             category=document.core_properties.category,
             comments=document.core_properties.comments,
             content_status=document.core_properties.content_status,
-            created=document.core_properties.created,
+            created=document.core_properties.created.isoformat() if document.core_properties.created else None,
             identifier=document.core_properties.identifier,
             keywords=document.core_properties.keywords,
             language=document.core_properties.language,
             last_modified_by=document.core_properties.last_modified_by,
-            last_printed=document.core_properties.last_printed,
-            modified=document.core_properties.modified,
+            last_printed=document.core_properties.last_printed.isoformat()
+            if document.core_properties.last_printed
+            else None,
+            modified=document.core_properties.modified.isoformat() if document.core_properties.modified else None,
             revision=document.core_properties.revision,
             subject=document.core_properties.subject,
             title=document.core_properties.title,

releasenotes/notes/docxmetadata-json-serializable-e4205ce70d042aed.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    The metadata produced by `DOCXToDocument` component is now JSON serializable.
+    Previously, it contained `datetime` objects automatically extracted from DOCX files, which are not JSON serializable.
+    Now, the `datetime` objects are converted to strings.

test/components/converters/test_docx_file_to_document.py

@@ -1,5 +1,5 @@
 import logging
-import datetime
+import json
 
 import pytest
 
@@ -34,13 +34,13 @@ class TestDOCXToDocument:
                 category="",
                 comments="",
                 content_status="",
-                created=datetime.datetime(2024, 6, 9, 21, 17, tzinfo=datetime.timezone.utc),
+                created="2024-06-09T21:17:00+00:00",
                 identifier="",
                 keywords="",
                 language="",
                 last_modified_by="Carlos Fernández Lorán",
                 last_printed=None,
-                modified=datetime.datetime(2024, 6, 9, 21, 27, tzinfo=datetime.timezone.utc),
+                modified="2024-06-09T21:27:00+00:00",
                 revision=2,
                 subject="",
                 title="",
@@ -48,7 +48,7 @@ class TestDOCXToDocument:
             ),
         }
 
-    def test_run_with_meta_overwrites(self, test_files_path, docx_converter):
+    def test_run_with_additional_meta(self, test_files_path, docx_converter):
         paths = [test_files_path / "docx" / "sample_docx_1.docx"]
         output = docx_converter.run(sources=paths, meta={"language": "it", "author": "test_author"})
         doc = output["documents"][0]
@@ -59,13 +59,13 @@ class TestDOCXToDocument:
                 category="",
                 comments="",
                 content_status="",
-                created=datetime.datetime(2024, 6, 9, 21, 17, tzinfo=datetime.timezone.utc),
+                created="2024-06-09T21:17:00+00:00",
                 identifier="",
                 keywords="",
                 language="",
                 last_modified_by="Carlos Fernández Lorán",
                 last_printed=None,
-                modified=datetime.datetime(2024, 6, 9, 21, 27, tzinfo=datetime.timezone.utc),
+                modified="2024-06-09T21:27:00+00:00",
                 revision=2,
                 subject="",
                 title="",
@@ -82,7 +82,7 @@ class TestDOCXToDocument:
             assert "doc_1.txt and convert it" in caplog.text
             assert results["documents"] == []
 
-    def test_run_error_non_existent_file(self, test_files_path, docx_converter, caplog):
+    def test_run_error_non_existent_file(self, docx_converter, caplog):
         """
         Test if the component correctly handles errors.
         """
@@ -121,13 +121,13 @@ class TestDOCXToDocument:
             category="category",
             comments="comments",
             content_status="",
-            created=datetime.datetime(2024, 6, 9, 21, 17, tzinfo=datetime.timezone.utc),
+            created="2024-06-09T21:17:00+00:00",
             identifier="",
             keywords="",
             language="",
             last_modified_by="Carlos Fernández Lorán",
             last_printed=None,
-            modified=datetime.datetime(2024, 6, 9, 21, 27, tzinfo=datetime.timezone.utc),
+            modified="2024-06-09T21:27:00+00:00",
             revision=2,
             subject="",
             title="",
@@ -149,13 +149,13 @@ class TestDOCXToDocument:
                     "category": "category",
                     "comments": "comments",
                     "content_status": "",
-                    "created": datetime.datetime(2024, 6, 9, 21, 17, tzinfo=datetime.timezone.utc),
+                    "created": "2024-06-09T21:17:00+00:00",
                     "identifier": "",
                     "keywords": "",
                     "language": "",
                     "last_modified_by": "Carlos Fernández Lorán",
                     "last_printed": None,
-                    "modified": datetime.datetime(2024, 6, 9, 21, 27, tzinfo=datetime.timezone.utc),
+                    "modified": "2024-06-09T21:27:00+00:00",
                     "revision": 2,
                     "subject": "",
                     "title": "",
@@ -163,3 +163,7 @@ class TestDOCXToDocument:
                 },
             },
         }
+
+        # check it is JSON serializable
+        json_str = json.dumps(doc.to_dict(flatten=False))
+        assert json.loads(json_str) == doc.to_dict(flatten=False)