Add label classes

app/api/views/upload/label.py

@@ -0,0 +1,82 @@
+import abc
+from typing import Any
+
+from pydantic import BaseModel
+
+
+class Label(BaseModel, abc.ABC):
+
+    @abc.abstractmethod
+    def has_name(self) -> bool:
+        raise NotImplementedError()
+
+    @property
+    @abc.abstractmethod
+    def name(self) -> str:
+        raise NotImplementedError()
+
+    @classmethod
+    def parse(cls, obj: Any):
+        raise NotImplementedError()
+
+    def __hash__(self):
+        return hash(tuple(self.dict()))
+
+
+class CategoryLabel(Label):
+    label: str
+
+    def has_name(self) -> bool:
+        return True
+
+    @property
+    def name(self) -> str:
+        return self.label
+
+    @classmethod
+    def parse(cls, obj: Any):
+        if isinstance(obj, str):
+            return cls(label=obj)
+        raise TypeError(f'{obj} is not str.')
+
+
+class OffsetLabel(Label):
+    label: str
+    start_offset: int
+    end_offset: int
+
+    def has_name(self) -> bool:
+        return True
+
+    @property
+    def name(self) -> str:
+        return self.label
+
+    @classmethod
+    def parse(cls, obj: Any):
+        if isinstance(obj, list):
+            columns = ['label', 'start_offset', 'end_offset']
+            obj = zip(columns, obj)
+            return cls.parse_obj(obj)
+        elif isinstance(obj, dict):
+            return cls.parse_obj(obj)
+        else:
+            raise TypeError(f'{obj} is invalid type.')
+
+
+class TextLabel(Label):
+    text: str
+
+    def has_name(self) -> bool:
+        return False
+
+    @property
+    def name(self) -> str:
+        return self.text
+
+    @classmethod
+    def parse(cls, obj: Any):
+        if isinstance(obj, str):
+            return cls(text=obj)
+        else:
+            raise TypeError(f'{obj} is not str.')