产地证是在哪个网站上做,网站平台建设实训体会,新开的网站怎么做seo优化,网站建设的工作描述文章目录 示例一:常见装饰器编写重试机制示例二#xff1a;使用类实现装饰器示例三#xff1a;使用函数装饰器并返回闭包示例四#xff1a;使用 wrapt 模块 示例一:常见装饰器编写重试机制
示例代码
import time
import traceback
import logging
from typing import Call… 文章目录 示例一:常见装饰器编写重试机制示例二使用类实现装饰器示例三使用函数装饰器并返回闭包示例四使用 wrapt 模块 示例一:常见装饰器编写重试机制
示例代码
import time
import traceback
import logging
from typing import Callable
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.common.exceptions import NoSuchElementException, WebDriverException, TimeoutException
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC# 设置日志配置
logging.basicConfig(levellogging.ERROR)
logger logging.getLogger(__name__)# 假设 DOME 是一个配置字典用于控制 DEBUG 模式
DOME {DEBUG: False,debug: False
}def exr_func(*args, **kwargs):# 在每次重试前执行的操作可以在此添加刷新页面等逻辑driver kwargs.get(driver)if driver:driver.refresh()time.sleep(2) # 等待页面刷新完成def dec_retry(num1, exr: Callable lambda *_, **__: None, catchException, excludeException, out_errorTrue):装饰器重复执行func并忽略异常超过次数抛出异常或返回空此函数默认输出异常信息def decorator(func):def dec(*args, **kwargs):for i in range(1, num 1):try:return func(*args, **kwargs)except exclude as err:raise errexcept catch as err:logger.error(f第 {i} 次执行失败)if out_error:logger.error(err, traceback.format_exc(), sep\n)if DOME.get(DEBUG) or DOME.get(debug):logger.error(已开启 DEBUG 模式直接抛出异常)raise errif i num:logger.error(f已执行 {num} 次抛出异常)raise errlogger.error(开始重试)exr(*args, **kwargs)return decreturn decoratordec_retry(num3, exrexr_func, catch(NoSuchElementException, WebDriverException, TimeoutException))
def login(driver, username, password):# 访问登录页面driver.get(https://example.com/login)# 等待页面加载完成WebDriverWait(driver, 10).until(EC.presence_of_element_located((By.ID, username)))# 输入用户名username_field driver.find_element(By.ID, username)username_field.send_keys(username)# 输入密码password_field driver.find_element(By.ID, password)password_field.send_keys(password)# 点击登录按钮login_button driver.find_element(By.ID, loginButton)login_button.click()# 等待页面加载完成并检查是否登录成功WebDriverWait(driver, 10).until(EC.presence_of_element_located((By.ID, logoutButton)))print(登录成功)return Truedef main():# 设置WebDriverdriver webdriver.Chrome()username your_usernamepassword your_passwordtry:login(driver, username, password, driverdriver)except Exception as e:logger.error(f最终登录失败异常: {e})driver.quit()if __name__ __main__:main()代码解释
日志配置: 设置日志记录配置用于输出错误信息。exr_func 函数: 定义了在每次重试前执行的操作例如刷新页面。dec_retry 装饰器: 实现了重试机制捕获指定异常在重试次数用尽前会执行 exr_func 函数。login 函数: 实现具体的登录操作并被 dec_retry 装饰器装饰。main 函数: 设置 WebDriver尝试登录并在失败时输出日志信息。
示例二使用类实现装饰器
类装饰器可以更灵活地管理状态并且可以更好地组织复杂的逻辑。
import time
import traceback
import logging
from typing import Callable
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.common.exceptions import NoSuchElementException, WebDriverException, TimeoutException
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC# 设置日志配置
logging.basicConfig(levellogging.ERROR)
logger logging.getLogger(__name__)# 假设 DOME 是一个配置字典用于控制 DEBUG 模式
DOME {DEBUG: False,debug: False
}def exr_func(*args, **kwargs):driver kwargs.get(driver)if driver:driver.refresh()time.sleep(2) # 等待页面刷新完成class RetryDecorator:def __init__(self, num1, exr: Callable lambda *_, **__: None, catchException, excludeException, out_errorTrue):self.num numself.exr exrself.catch catchself.exclude excludeself.out_error out_errordef __call__(self, func):def wrapped_func(*args, **kwargs):for i in range(1, self.num 1):try:return func(*args, **kwargs)except self.exclude as err:raise errexcept self.catch as err:logger.error(f第 {i} 次执行失败)if self.out_error:logger.error(err, traceback.format_exc(), sep\n)if DOME.get(DEBUG) or DOME.get(debug):logger.error(已开启 DEBUG 模式直接抛出异常)raise errif i self.num:logger.error(f已执行 {self.num} 次抛出异常)raise errlogger.error(开始重试)self.exr(*args, **kwargs)return wrapped_funcRetryDecorator(num3, exrexr_func, catch(NoSuchElementException, WebDriverException, TimeoutException))
def login(driver, username, password):driver.get(https://example.com/login)WebDriverWait(driver, 10).until(EC.presence_of_element_located((By.ID, username)))username_field driver.find_element(By.ID, username)username_field.send_keys(username)password_field driver.find_element(By.ID, password)password_field.send_keys(password)login_button driver.find_element(By.ID, loginButton)login_button.click()WebDriverWait(driver, 10).until(EC.presence_of_element_located((By.ID, logoutButton)))print(登录成功)return Truedef main():driver webdriver.Chrome()username your_usernamepassword your_passwordtry:login(driver, username, password, driverdriver)except Exception as e:logger.error(f最终登录失败异常: {e})driver.quit()if __name__ __main__:main()示例三使用函数装饰器并返回闭包
使用闭包使代码更简洁。
import time
import traceback
import logging
from typing import Callable
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.common.exceptions import NoSuchElementException, WebDriverException, TimeoutException
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EClogging.basicConfig(levellogging.ERROR)
logger logging.getLogger(__name__)DOME {DEBUG: False,debug: False
}def exr_func(*args, **kwargs):driver kwargs.get(driver)if driver:driver.refresh()time.sleep(2)def dec_retry(num1, exr: Callable lambda *_, **__: None, catchException, excludeException, out_errorTrue):def decorator(func):def wrapped_func(*args, **kwargs):for i in range(1, num 1):try:return func(*args, **kwargs)except exclude as err:raise errexcept catch as err:logger.error(f第 {i} 次执行失败)if out_error:logger.error(err, traceback.format_exc(), sep\n)if DOME.get(DEBUG) or DOME.get(debug):logger.error(已开启 DEBUG 模式直接抛出异常)raise errif i num:logger.error(f已执行 {num} 次抛出异常)raise errlogger.error(开始重试)exr(*args, **kwargs)return wrapped_funcreturn decoratordec_retry(num3, exrexr_func, catch(NoSuchElementException, WebDriverException, TimeoutException))
def login(driver, username, password):driver.get(https://example.com/login)WebDriverWait(driver, 10).until(EC.presence_of_element_located((By.ID, username)))username_field driver.find_element(By.ID, username)username_field.send_keys(username)password_field driver.find_element(By.ID, password)password_field.send_keys(password)login_button driver.find_element(By.ID, loginButton)login_button.click()WebDriverWait(driver, 10).until(EC.presence_of_element_located((By.ID, logoutButton)))print(登录成功)return Truedef main():driver webdriver.Chrome()username your_usernamepassword your_passwordtry:login(driver, username, password, driverdriver)except Exception as e:logger.error(f最终登录失败异常: {e})driver.quit()if __name__ __main__:main()示例四使用 wrapt 模块
wrapt 是一个强大的装饰器库可以更轻松地编写装饰器特别是处理复杂逻辑时。
import time
import traceback
import logging
import wrapt
from typing import Callable
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.common.exceptions import NoSuchElementException, WebDriverException, TimeoutException
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EClogging.basicConfig(levellogging.ERROR)
logger logging.getLogger(__name__)DOME {DEBUG: False,debug: False
}def exr_func(*args, **kwargs):driver kwargs.get(driver)if driver:driver.refresh()time.sleep(2)def dec_retry(num1, exr: Callable lambda *_, **__: None, catchException, excludeException, out_errorTrue):wrapt.decoratordef wrapper(wrapped, instance, args, kwargs):for i in range(1, num 1):try:return wrapped(*args, **kwargs)except exclude as err:raise errexcept catch as err:logger.error(f第 {i} 次执行失败)if out_error:logger.error(err, traceback.format_exc(), sep\n)if DOME.get(DEBUG) or DOME.get(debug):logger.error(已开启 DEBUG 模式直接抛出异常)raise errif i num:logger.error(f已执行 {num} 次抛出异常)raise errlogger.error(开始重试)exr(*args, **kwargs)return wrapperdec_retry(num3, exrexr_func, catch(NoSuchElementException, WebDriverException, TimeoutException))
def login(driver, username, password):driver.get(https://example.com/login)WebDriverWait(driver, 10).until(EC.presence_of_element_located((By.ID, username)))username_field driver.find_element(By.ID, username)username_field.send_keys(username)password_field driver.find_element(By.ID, password)password_field.send_keys(password)login_button driver.find_element(By.ID, loginButton)login_button.click()WebDriverWait(driver, 10).until(EC.presence_of_element_located((By.ID, logoutButton)))print(登录成功)return Truedef main():driver webdriver.Chrome()username your_usernamepassword your_passwordtry:login(driver, username, password, driverdriver)except Exception as e:logger.error(f最终登录失败异常: {e})driver.quit()if __name__ __main__:main()
