Module `licenseware.decorators.failsafe_decorator`

Expand source code

import traceback
from functools import wraps
from licenseware.utils.logger import log


def failsafe(*dargs, fail_code=0, success_code=0):
    """
        Prevents a function to raise an exception and break the app.
        Returns a string with the exception and saves the traceback in app.log
        If fail_code or success_code is specified then a json response will be returned.
        
        @failsafe
        def fun1(): raise Exception("test")
        print(fun1())
        >>test

        @failsafe(fail_code=500)
        def fun2(): raise Exception("test")
        print(fun2())
        >> ({'status': 'fail', 'message': 'test'}, 500)

        @failsafe(fail_code=500, success_code=200)
        def fun3(): return "test"
        print(fun3())
        >> ({'status': 'success', 'message': 'test'}, 200)
        
        This decorator is very useful to prevent app crashes but still logging them
        
        Ex:
        
        @api.route('/)
        @failsafe(fail_code=500)
        def viewfunc():
            raise Exception("Inevitable app crash")
        
        When called the route up will return:
        {'status': 'fail', 'message': "Inevitable app crash"}, 500
        
        Unknown/Unhandled errors maybe not so useful for the user.
        
        But with the errors you raised there is no issue.
        
    """
    
    def _decorator(f):
        @wraps(f)
        def wrapper(*args, **kwargs):
            try:
                response = f(*args, **kwargs)
                if success_code:
                    return {"status": "success", "message": response}, success_code
                return response
            except Exception as err:
                log.error(traceback.format_exc())
                if fail_code:
                    return {"status": "fail", "message": str(err)}, fail_code
                return str(err)
        return wrapper

    return _decorator(dargs[0]) if dargs and callable(dargs[0]) else _decorator

Functions

def failsafe(*dargs, fail_code=0, success_code=0)

Prevents a function to raise an exception and break the app. Returns a string with the exception and saves the traceback in app.log If fail_code or success_code is specified then a json response will be returned.

@failsafe def fun1(): raise Exception("test") print(fun1())

test

@failsafe(fail_code=500) def fun2(): raise Exception("test") print(fun2())

({'status': 'fail', 'message': 'test'}, 500)

@failsafe(fail_code=500, success_code=200) def fun3(): return "test" print(fun3())

({'status': 'success', 'message': 'test'}, 200)

This decorator is very useful to prevent app crashes but still logging them

Ex:

@api.route('/) @failsafe(fail_code=500) def viewfunc(): raise Exception("Inevitable app crash")

When called the route up will return: {'status': 'fail', 'message': "Inevitable app crash"}, 500

Unknown/Unhandled errors maybe not so useful for the user.

But with the errors you raised there is no issue.

Expand source code

def failsafe(*dargs, fail_code=0, success_code=0):
    """
        Prevents a function to raise an exception and break the app.
        Returns a string with the exception and saves the traceback in app.log
        If fail_code or success_code is specified then a json response will be returned.
        
        @failsafe
        def fun1(): raise Exception("test")
        print(fun1())
        >>test

        @failsafe(fail_code=500)
        def fun2(): raise Exception("test")
        print(fun2())
        >> ({'status': 'fail', 'message': 'test'}, 500)

        @failsafe(fail_code=500, success_code=200)
        def fun3(): return "test"
        print(fun3())
        >> ({'status': 'success', 'message': 'test'}, 200)
        
        This decorator is very useful to prevent app crashes but still logging them
        
        Ex:
        
        @api.route('/)
        @failsafe(fail_code=500)
        def viewfunc():
            raise Exception("Inevitable app crash")
        
        When called the route up will return:
        {'status': 'fail', 'message': "Inevitable app crash"}, 500
        
        Unknown/Unhandled errors maybe not so useful for the user.
        
        But with the errors you raised there is no issue.
        
    """
    
    def _decorator(f):
        @wraps(f)
        def wrapper(*args, **kwargs):
            try:
                response = f(*args, **kwargs)
                if success_code:
                    return {"status": "success", "message": response}, success_code
                return response
            except Exception as err:
                log.error(traceback.format_exc())
                if fail_code:
                    return {"status": "fail", "message": str(err)}, fail_code
                return str(err)
        return wrapper

    return _decorator(dargs[0]) if dargs and callable(dargs[0]) else _decorator