1"""LICENSE 

2Copyright 2020 Hermann Krumrey <hermann@krumreyh.com> 

3 

4This file is part of jerrycan. 

5 

6jerrycan is free software: you can redistribute it and/or modify 

7it under the terms of the GNU General Public License as published by 

8the Free Software Foundation, either version 3 of the License, or 

9(at your option) any later version. 

10 

11jerrycan is distributed in the hope that it will be useful, 

12but WITHOUT ANY WARRANTY; without even the implied warranty of 

13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 

14GNU General Public License for more details. 

15 

16You should have received a copy of the GNU General Public License 

17along with jerrycan. If not, see <http://www.gnu.org/licenses/>. 

18LICENSE""" 

19 

20import sentry_sdk 

21from functools import wraps 

22from typing import Callable 

23from flask import jsonify, make_response, request 

24from werkzeug.exceptions import Unauthorized 

25from jerrycan.exceptions import ApiException 

26from jerrycan.base import app 

27 

28 

29def api(func: Callable) -> Callable: 

30 """ 

31 Decorator that handles common API patterns and ensures that 

32 the JSON response will always follow a certain pattern 

33 :param func: The function to wrap 

34 :return: The wrapper function 

35 """ 

36 

37 @wraps(func) 

38 def wrapper(*args, **kwargs): 

39 """ 

40 Tries running the function and checks for errors 

41 :param args: args 

42 :param kwargs: kwargs 

43 :return: The JSON response including an appropriate HTTP status code 

44 """ 

45 code = 200 

46 response = {"status": "ok"} 

47 

48 try: 

49 is_json = request.content_type is not None \ 

50 and request.content_type.startswith("application/json") \ 

51 and request.is_json \ 

52 and isinstance(request.get_json(silent=True), dict) 

53 if request.method in ["POST", "PUT", "DELETE"] and not is_json: 

54 raise ApiException("not in json format", 400) 

55 

56 try: 

57 response["data"] = func(*args, **kwargs) 

58 except ApiException as e: 

59 if e.status_code >= 500: 

60 app.logger.error(f"Caught exception in API: {e}") 

61 sentry_sdk.capture_exception(e) 

62 raise e 

63 except (KeyError, TypeError, ValueError) as e: 

64 raise e 

65 except BaseException: 

66 raise ApiException("server error", 500) 

67 

68 except (KeyError, TypeError, ValueError, ApiException) as e: 

69 

70 response["status"] = "error" 

71 

72 if isinstance(e, ApiException): 

73 code = e.status_code 

74 response["reason"] = e.reason 

75 

76 else: 

77 code = 400 

78 response["reason"] = "bad request: {}".format(type(e).__name__) 

79 

80 return make_response(jsonify(response), code) 

81 return wrapper 

82 

83 

84def api_login_required(func: Callable) -> Callable: 

85 """ 

86 Decorator to make unauthorized API calls respond with JSON properly 

87 :param func: The function to wrap 

88 :return: The wrapped function 

89 """ 

90 

91 @wraps(func) 

92 def wrapper(*args, **kwargs): 

93 """ 

94 Checks if flask-login throws an Unauthorized exception. If so, 

95 re-wrap the response in JSON 

96 :param args: The function arguments 

97 :param kwargs: The function keyword arguments 

98 :return: The newly wrapped response, 

99 or just the plain response if authorized 

100 """ 

101 

102 try: 

103 resp = func(*args, **kwargs) 

104 return resp 

105 except Unauthorized: 

106 return make_response( 

107 jsonify({"status": "error", "reason": "unauthorized"}), 401 

108 ) 

109 

110 return wrapper