Add a register api

- Add a register api
- Change requirements, which flask version should be over 2.0

latest version/api/api_code.py

@@ -1,19 +1,34 @@
+from flask import jsonify
+
+
 def code_get_msg(code):
     # api接口code获取msg，返回字符串
     msg = {
-        '0': '',
-        '-1': 'See status code',
-        '-2': 'No data',
-        '-3': 'No data or user',
-        '-4': 'No user_id',
-        '-100': 'Wrong post data',
-        '-101': 'Wrong data type',
-        '-102': 'Wrong query parameter',
-        '-103': 'Wrong sort parameter',
-        '-104': 'Wrong sort order parameter',
-        '-201': 'Wrong username or password',
-        '-202': 'User is banned',
-        '-999': 'Unknown error'
+        0: '',
+        -1: 'See status code',
+        -2: 'No data',
+        -3: 'No data or user',
+        -4: 'No user_id',
+        -100: 'Wrong post data',
+        -101: 'Wrong data type',
+        -102: 'Wrong query parameter',
+        -103: 'Wrong sort parameter',
+        -104: 'Wrong sort order parameter',
+        -201: 'Wrong username or password',
+        -202: 'User is banned',
+        -203: 'Username exists',
+        -204: 'Email address exists',
+        -999: 'Unknown error'
     }
 
-    return msg[str(code)]
+    return msg[code]
+
+
+def return_encode(code: int = 0, data: dict = {}, status: int = 200, msg: str = ''):
+    # 构造返回，返回jsonify处理过后的response_class
+    if msg == '':
+        msg = code_get_msg(code)
+    if code < 0:
+        return jsonify({'status': status, 'code': code, 'data': {}, 'msg': msg})
+    else:
+        return jsonify({'status': status, 'code': code, 'data': data, 'msg': msg})