model.OriginVisit: Make obsolete fields optional

Related to T2310

swh/model/hypothesis_strategies.py

@@ -157,9 +157,9 @@ def origin_visits_d():
         visit=integers(1, 1000),
         origin=urls(),
         date=aware_datetimes(),
-        status=sampled_from(["ongoing", "full", "partial"]),
         type=pgsql_text(),
-        snapshot=optional(sha1_git()),
+        status=none(),
+        snapshot=none(),
         metadata=none(),
     )
 

swh/model/model.py

@@ -233,16 +233,15 @@ class OriginVisit(BaseModel):
 
     origin = attr.ib(type=str, validator=type_validator())
     date = attr.ib(type=datetime.datetime, validator=type_validator())
-    status = attr.ib(
-        type=str, validator=attr.validators.in_(["ongoing", "full", "partial"])
-    )
     type = attr.ib(type=str, validator=type_validator())
-    snapshot = attr.ib(type=Optional[Sha1Git], validator=type_validator())
+    """Should not be set before calling 'origin_visit_add()'."""
+    visit = attr.ib(type=Optional[int], validator=type_validator(), default=None)
+
+    status = attr.ib(type=Optional[str], validator=type_validator(), default=None)
+    snapshot = attr.ib(type=Optional[Sha1Git], validator=type_validator(), default=None)
     metadata = attr.ib(
         type=Optional[Dict[str, object]], validator=type_validator(), default=None
     )
-    visit = attr.ib(type=Optional[int], validator=type_validator(), default=None)
-    """Should not be set before calling 'origin_visit_add()'."""
 
     def to_dict(self):
         """Serializes the date as a string and omits the visit id if it is