feat: 站内信 (#6183)

* 添加站内信

* s

* s

* 添加接口

* fix

* fix

* 重构了一些

* 完成

* 完善

* s

* s

* s

* s

* s

* s

* 测试ok

* 替换业务中发送消息的方式

* 修改

* s

* 去掉 update 兼容 create

* 添加 unread total 接口

* 调整json字段

Co-authored-by: xinwen <coderWen@126.com>

apps/notifications/backends/__init__.py

@@ -0,0 +1,36 @@
+from django.utils.translation import gettext_lazy as _
+from django.db import models
+
+from .dingtalk import DingTalk
+from .email import Email
+from .site_msg import SiteMessage
+from .wecom import WeCom
+
+
+class BACKEND(models.TextChoices):
+    EMAIL = 'email', _('Email')
+    WECOM = 'wecom', _('WeCom')
+    DINGTALK = 'dingtalk', _('DingTalk')
+    SITE_MSG = 'site_msg', _('Site message')
+
+    @property
+    def client(self):
+        client = {
+            self.EMAIL: Email,
+            self.WECOM: WeCom,
+            self.DINGTALK: DingTalk,
+            self.SITE_MSG: SiteMessage
+        }[self]
+        return client
+
+    def get_account(self, user):
+        return self.client.get_account(user)
+
+    @property
+    def is_enable(self):
+        return self.client.is_enable()
+
+    @classmethod
+    def filter_enable_backends(cls, backends):
+        enable_backends = [b for b in backends if cls(b).is_enable]
+        return enable_backends