♻️(back) replace Ypy by pycrdt

Ypy is deprecated and unmaintained. We have problem with parsing
existing documents. We replace it by pycrdt, library actively maintained
and without the issues we have with Ypy.

src/backend/core/tests/documents/test_api_documents_duplicate.py

@@ -11,9 +11,9 @@ from django.conf import settings
 from django.core.files.storage import default_storage
 from django.utils import timezone
 
+import pycrdt
 import pytest
 import requests
-import y_py
 from rest_framework.test import APIClient
 
 from core import factories, models
@@ -84,13 +84,14 @@ def test_api_documents_duplicate_success(index):
     image_refs = [get_image_refs(doc_id) for doc_id in document_ids]
 
     # Create document content with the first image only
-    ydoc = y_py.YDoc()  # pylint: disable=no-member
-    with ydoc.begin_transaction() as txn:
-        xml_fragment = ydoc.get_xml_element("document-store")
-        xml_fragment.push_xml_element(txn, "image").set_attribute(
-            txn, "src", image_refs[0][1]
-        )
-    update = y_py.encode_state_as_update(ydoc)  # pylint: disable=no-member
+    ydoc = pycrdt.Doc()
+    fragment = pycrdt.XmlFragment(
+        [
+            pycrdt.XmlElement("img", {"src": image_refs[0][1]}),
+        ]
+    )
+    ydoc["document-store"] = fragment
+    update = ydoc.get_update()
     base64_content = base64.b64encode(update).decode("utf-8")
 
     # Create documents

src/backend/core/tests/documents/test_api_documents_update_extract_attachments.py

@@ -5,8 +5,8 @@ Test extract-attachments on document update in docs core app.
 import base64
 from uuid import uuid4
 
+import pycrdt
 import pytest
-import y_py
 from rest_framework.test import APIClient
 
 from core import factories
@@ -16,14 +16,15 @@ pytestmark = pytest.mark.django_db
 
 def get_ydoc_with_mages(image_keys):
     """Return a ydoc from text for testing purposes."""
-    ydoc = y_py.YDoc()  # pylint: disable=no-member
-    with ydoc.begin_transaction() as txn:
-        xml_fragment = ydoc.get_xml_element("document-store")
-        for key in image_keys:
-            xml_image = xml_fragment.push_xml_element(txn, "image")
-            xml_image.set_attribute(txn, "src", f"http://localhost/media/{key:s}")
-
-    update = y_py.encode_state_as_update(ydoc)  # pylint: disable=no-member
+    ydoc = pycrdt.Doc()
+    fragment = pycrdt.XmlFragment(
+        [
+            pycrdt.XmlElement("img", {"src": f"http://localhost/media/{key:s}"})
+            for key in image_keys
+        ]
+    )
+    ydoc["document-store"] = fragment
+    update = ydoc.get_update()
     return base64.b64encode(update).decode("utf-8")