feat(fields): migrate from json to orjson for improved performance

migrate field serialization/deserialization to use `orjson` instead of `json` for better performance and ensure compatibility with decryption using `cryptography.fernet`. Handle potential invalid tokens and decoding errors gracefully.

schon/fields.py

@@ -1,5 +1,5 @@
-import json
+import orjson
-
+from cryptography.fernet import InvalidToken
 from encrypted_fields.fields import EncryptedTextField
 
 
@@ -18,16 +18,20 @@ class EncryptedJSONTextField(EncryptedTextField):
 
     def get_prep_value(self, value):
         if value is not None and not isinstance(value, str):
-            value = json.dumps(value, default=str)
+            value = orjson.dumps(value, default=str).decode("utf-8")
         return super().get_prep_value(value)
 
     def from_db_value(self, value, expression, connection):
-        value = super().from_db_value(value, expression, connection)
         if value is None:
             return None
         if isinstance(value, str):
             try:
-                return json.loads(value)
+                value = self.f.decrypt(value.encode("utf-8")).decode("utf-8")
+            except (InvalidToken, UnicodeEncodeError):
+                pass
+        if isinstance(value, str):
+            try:
+                return orjson.loads(value)
             except (ValueError, TypeError):
                 pass
         return value
@@ -35,9 +39,16 @@ class EncryptedJSONTextField(EncryptedTextField):
     def to_python(self, value):
         if isinstance(value, (dict, list)):
             return value
+        if value is None:
+            return value
         if isinstance(value, str):
+            if not hasattr(self, "_already_decrypted"):
+                try:
+                    value = self.f.decrypt(value.encode("utf-8")).decode("utf-8")
+                except (InvalidToken, UnicodeEncodeError):
+                    pass
             try:
-                return json.loads(value)
+                return orjson.loads(value)
             except (ValueError, TypeError):
                 pass
         return value