改进 netease BaseModel 的 __getattribute__ 实现

区分 None 与空列表/空字符串的区别：None 代表该字段没有
被初始化，空列表或者空字符串表示初始化了，但是数据内容为空。

fuocore/models.py

@@ -1,5 +1,12 @@
 # -*- coding: utf-8 -*-
 
+"""
+fuocore.model
+~~~~~~~~~~~~~
+
+这个模块对音乐相关模型进行了定义，声明了各模型的属性。
+"""
+
 from enum import Enum
 
 
@@ -130,6 +137,11 @@ def __eq__(self, other):
 
     @classmethod
     def get(cls, identifier):
+        """获取 Model 详细信息
+
+        NOTE: 字段值如果是 None 的话，说明之前这个字段没有被初始化过。
+        所以在调用 get 接口之后，需要将每个字段初始化为非 None。
+        """
         raise NotImplementedError
 
     @classmethod

fuocore/netease/models.py

@@ -32,7 +32,8 @@ class Meta:
     def __getattribute__(self, name):
         cls = type(self)
         value = object.__getattribute__(self, name)
-        if name in cls._detail_fields and not value:
+        if name in cls._detail_fields and value is None:
+            logger.debug('Field %s value is None, get model detail first.')
             obj = cls.get(self.identifier)
             for field in cls._detail_fields:
                 setattr(self, field, getattr(obj, field))
@@ -163,7 +164,7 @@ class NArtistModel(ArtistModel, NBaseModel):
     def get(cls, identifier):
         artist_data = cls._api.artist_infos(identifier)
         artist = artist_data['artist']
-        artist['songs'] = artist_data['hotSongs']
+        artist['songs'] = artist_data['hotSongs'] or []
         artist, _ = NeteaseArtistSchema(strict=True).load(artist)
         return artist
 

fuocore/provider.py

@@ -1,5 +1,12 @@
 # -*- coding: utf-8 -*-
 
+"""
+fuocore.provider
+~~~~~~~~~~~~~~~~
+
+provider 意为音乐提供方
+"""
+
 from abc import ABC, abstractmethod
 from fuocore.models import (
     SongModel,