decorator

问题 In Flask, how do you get a route value (eg. '/admin') inside a decorator? I need to pass certain string to the DB depending on which route was used (and they all use the same decorator). @app.route('/admin') @decorator def admin(data): do_something(data) I couldn't find information about how to do it in Python. Is it possible? 回答1: You can define a new decorator which get the current route path then do something with it: from functools import wraps from flask import request def do_st_with

问题 I have an issue where I would like my handler to use data generated from the handlers: UpdateUserProfileImageCommandHandlerAuthorizeDecorator UpdateUserProfileImageCommandHandlerUploadDecorator UpdateUserProfileImageCommandHandler My problem is both architectural and performance. UpdateUserCommandHandlerAuthorizeDecorator makes a call to the repository (entityframework) to authorize the user. I have other decorators similar to this that should use and modify entities and send it up the chain.

问题 Is there a reason why calling the security authentication property principal.displayName in a decorator would cause a problem? I'm setting it as a variable in a sitemesh decorator: <c:set var="displayName"> <sec:authentication property="principal.displayName" /> </c:set> But it generates this exception: java.lang.RuntimeException: javax.servlet.ServletException: javax.servlet.jsp.JspException: Invalid property 'principal.displayName' o f bean class [org.springframework.security.authentication

问题 I'm reading several docs on validation in ASP.NET MVC . Ignoring those that suggest to reinvent the wheel writing your own validation logic, most articles advocate the use of xVal or Data Annotation Validators, both of which allow declarative validation through decorating models' properties(*). I think I'll go for xVal , as it seems to be the most suggested (and thus, I hope, supported). What puzzles me is that I'm using Linq to SQL , and my models are declared in an automatically generated

问题 I am trying to understand UML diagram describing Decorator Pattern at link below http://www.dofactory.com/Patterns/PatternDecorator.aspx I don't understand why there is a "Aggregation" relation between Decorator and Component. I believe it should be composition as Decorator cannot exist without the base component. 回答1: Composition is stronger that aggregation, it usually means that the object takes ownership of its components. This is not the case in this situation because a decorator doesn't

问题 While trying to figure out if a function is called with the @decorator syntax, we realized that inspect has a different behaviour when looking at a decorated class that inherits from a superclass. The following behaviour was found with CPython 3.6.2 under Windows 10. It was also reproduced in CPython 3.7.0 under Linux 64 bits. import inspect def decorate(f): lines = inspect.stack()[1].code_context print(f.__name__, lines) return f @decorate class Foo: pass @decorate class Bar(dict): pass

问题 I'm trying to implement threading(with using decorators) to my application, but can't understand some things about locks and managing threads. import threading def run_in_thread(fn): def run(*k, **kw): t = threading.Thread(target=fn, args=k, kwargs=kw) t.start() return run class A: @run_in_thread def method1(self): for x in range(10000): print x @run_in_thread def method2(self): for y in list('wlkefjwfejwiefwhfwfkjshkjadgfjhkewgfjwjefjwe'): print y def stop_thread(self): pass c = A() c

问题 Is there any way to create a custom FrameworkContentElement (or an Inline ) that draws a diagonal line over its content? Something like Strike-through decoration but with a diagonal shape: It is not possible to inherent from TextDecoration or TextEffect (they are sealed). Any idea? 回答1: UPDATE : I tried to create an example as minimal as possible. In more complex scenarios you will have to extend this. Here is how it looks: this is the corresponding xaml: <AdornerDecorator> <StackPanel>

问题 If I'm using a module/class I have no control over, how would I decorate one of the methods? I understand I can: my_decorate_method(target_method)() but I'm looking to have this happen wherever target_method is called without having to do a search/replace. Is it even possible? 回答1: Yes it's possible, but there are several problems. First whet you get method from class in obvious way you get a warper object but not the function itself. class X(object): def m(self,x): print x print X.m #>>>

问题 I've been reading up on decorators in JavaScript, and think I'm getting the basic premise. Decorators are functions, they receive as a or several parameters what they should decorate, and return the result. But I came over a @withStyles decorated implementation in a React Boiler Plate project which I do not understand how works. import React, { Component, PropTypes } from 'react'; function withStyles(...styles) { return (BaseComponent) => class StyledComponent extends Component { static