[接口测试_B] 06 Pytest的setup和teardown

Posted 2021-04-24 开源优测

pytest实际上是python自带测试框架unittest的扩展，那么pytest是如何实现unittest中的setup和teardown的呢？

pytest初始化的类别和作用域

• 模块级别（Module level setup/teardown）：作用于一个模块内的所有class和def，对于所有class和def，setup和teardown只执行一次

def setup_module(module):

‍""" 

setup any state specific to the 
execution of the given module.

"""‍

def teardown_module(module):

""" 
teardown any state that was previously 
setup with a setup_module
method.
"""

• 类级别（Class level setup/teardown）：作用于一个class内中的所有test,所有用例只执行一次setup，当所有用例执行完成后，才会执行teardown

@classmethod
def setup_class(cls):

""" setup any state specific to the execution 
of the given class (which
usually contains tests).
"""


@classmethod
def teardown_class(cls):
 """ teardown any state that was previously 
setup with a call to
setup_class.
"""

• 方法和函数级别（Method and function level setup/teardown）：作用于单个测试用例，若用例没有执行（如被skip了）或失败了，则不会执行teardown

def setup_method(self, method):

""" 
setup any state tied to the execution 
of the given method in a
class. setup_method is invoked for 
every test method of a class.
"""


def teardown_method(self, method):

"""
teardown any state that was 
previously setup with a setup_method
call.
"""

若用例直接写在模块中，而不是在类中，则用：

def setup_function(function):

""" 
setup any state tied to the execution of the given function.
Invoked for every test function in the module.
"""

def teardown_function(function):

""" 
teardown any state that was previously setup with
 a setup_function call.
"""

• pytest.fixture()装饰函数，结合yield实现初始化和teardown
  举个例子(pytest）文档中的：

import smtplib
import pytest
@pytest.fixture(scope="module")def smtp():
    smtp = smtplib.SMTP("smtp.gmail.com", 587, timeout=5)
    
    yield smtp # provide the fixture value
    print("teardown smtp")


    smtp.close()

运行结果：

$ pytest -s -q --tb=no
FFteardown smtp2 failed in 0.12 seconds

pytest用例初始化操作的示例

为了体现初始化和环境恢复，本节演示采用邮件发送的脚本，可查看邮件发送的脚本：python发送邮件脚本或者参考文章：SMTP发送邮件。

1、setup_method(self, method)

• 在test_method.py中构建了3个测试用例，每个用例在执行前后都会执行setup_method/teardown_method连接smtp和断开smtp。

import smtplib
from email.mime.text import MIMEText
from email.header import Header
from email.mime.multipart import MIMEMultipart
import pytest

class TestSmtp():
    # 发件人和收件人,换成你自己的发件人、收件人qq号
    sender = "[e-mail]"
    receivers = "[e-mail]"

    # 邮箱服务器
    smtpserver = "smtp.qq.com"
    smtpport = 465

    # 连接邮箱服务器，qq邮箱和密码,换成自己的
    username = "[e-mail]"
    password = "qq mail's password"
    smtp = smtplib.SMTP_SSL()

    def setup_method(self, method):
        self.smtp.connect(self.smtpserver, self.smtpport)
        self.smtp.login(self.username, self.password)
        print("成功登录")

    def teardown_method(self, method):
        self.smtp.quit()
        print("断开连接")

    def test_send_text(self):
        # 邮件发送、接收人员，邮件标题、正文
        msg = MIMEText("微信公众号号：开源优测", "plain", "utf-8")
        msg["From"] = self.sender
        msg["To"] = self.receivers
        msg["Subject"] = Header("开源优测_DeepTest_from_chenlele_text", "utf-8")

        # 发送邮件
        self.smtp.sendmail(self.sender, self.receivers, msg.as_string())

    def test_send_html(self):
        msg = MIMEText("<p>微信公众号号：开源优测</p><a href='http://www.testingunion.com'>开源优测社区</a>>", 
        "html", 
        "utf-8")
        msg["From"] = self.sender
        msg["To"] = self.receivers
        msg["Subject"] = Header("开源优测_DeepTest_from_chenlele_html", "utf-8")

        # 发送邮件
        self.smtp.sendmail(self.sender, self.receivers, msg.as_string())

    def test_send_attchment(self):
        # 邮件格式说明、发送、接收人员信息、邮件标题
        msg = MIMEMultipart()
        msg["From"] = self.sender
        msg["To"] = self.receivers
        msg["Subject"] = Header("开源优测_DeepTest_from_chenlele", "utf-8")

        # 构建带附件的邮件正文
        msg.attach(MIMEText("微信公众号：开源优测", "plain", "utf-8")) 
    
        # 构造附件,多个附件同理
        attach1 = MIMEText(open("judge_leap.json", 'rb').read(), "base64", "utf-8")
        attach1["Content-Type"] = "application/octet-stream"

        # 这里filename随意写，将会在邮件中显示
        attach1["Content-Disposition"] = "attrachment;filename=code.py"
    
        # 关联附件到正文
        msg.attach(attach1)
        # 发送邮件
        self.smtp.sendmail(self.sender, self.receivers, msg.as_string())

• 查看结果，采用pytest -s -q 运行，-s 可以查看打印信息，-q减少输出信息：

  
  

  

  test_method结果.png

• 
  

2、setup_class(cls)

• 作用于class的setup_class/teardown_class，类中所有的用例只会执行一次，如图所示；

• ps:用例与test_method.py的一致，参考上一串代码。

test_class.png

3、setup_module(module)

• setup_module/teardown_module在一个模块内，只会执行一次，作用于模块内的所有用例

• 示例中构建了2个class和1个def，共4个用例，可以看到，4个用例只执行了一次module

test_module结果.png

test_module.py

import smtplib
from email.mime.text import MIMEText
from email.header import Header
from email.mime.multipart import MIMEMultipart
import pytest

info = {"sender": "[e-mail]", 
        "receivers": "[e-mail]",
        "smtpserver": "smtp.qq.com",
        "smtpport": 465,
        "username":"[e-mail]",
        "password": "yourpassword",
        "smtp": smtplib.SMTP_SSL()}

def setup_module(module):
    info["smtp"].connect(info["smtpserver"], info["smtpport"])
    info["smtp"].login(info["username"], info["password"])
    print("成功登录")def teardown_module(module):
    info["smtp"].quit()
    print("断开连接")

class TestSendText():
     def test_send_text(self):
        # 邮件发送、接收人员，邮件标题、正文
        msg = MIMEText("微信公众号号：开源优测", "plain", "utf-8")
        msg["From"] =info["sender"]
        msg["To"] = info["receivers"]
        msg["Subject"] = Header(
                "开源优测_DeepTest_from_chenlele_text", 
                "utf-8")

        # 发送邮件
        info["smtp"].sendmail(info["sender"], 
            info["receivers"], 
            msg.as_string())
    
     def test_send_html(self):
        msg = MIMEText("<p>微信公众号号：开源优测</p><a href='http://www.testingunion.com'>开源优测社区</a>>", 
        "html", 
        "utf-8")
        msg["From"] = info["sender"]
        msg["To"] = info["receivers"]
        msg["Subject"] = Header(
            "开源优测_DeepTest_from_chenlele_html", 
            "utf-8")

        # 发送邮件
        info["smtp"].sendmail(info["sender"], 
                info["receivers"], 
                msg.as_string())


class TestSendAttach():
    def test_send_attchment(self):
        # 邮件格式说明、发送、接收人员信息、邮件标题
        msg = MIMEMultipart()
        msg["From"] = info["sender"]
        msg["To"] = info["receivers"]
        msg["Subject"] = Header(
                "开源优测_DeepTest_from_chenlele", 
                "utf-8")

        # 构建带附件的邮件正文
        msg.attach(MIMEText("微信公众号：开源优测", 
                "plain", "utf-8")) 
    
        # 构造附件,多个附件同理
        attach1 = MIMEText(open("judge_leap.json", 'rb').read(), "base64", "utf-8")
        attach1["Content-Type"] = "application/octet-stream"

        # 这里filename随意写，将会在邮件中显示
        attach1["Content-Disposition"] = "attrachment;filename=code.py"
    
        # 关联附件到正文
        msg.attach(attach1)

        # 发送邮件
        info["smtp"].sendmail(info["sender"], 
                info["receivers"], 
                msg.as_string())


def test_send_text_out():
    # 邮件发送、接收人员，邮件标题、正文
    msg = MIMEText("微信公众号号：开源优测", "plain", "utf-8")
    msg["From"] =info["sender"]
    msg["To"] = info["receivers"]
    msg["Subject"] = Header("class外的用例执行", "utf-8")

    # 发送邮件
    info["smtp"].sendmail(info["sender"], info["receivers"], msg.as_string())

4、pytest.fixture()

• pytest.fixture采用yield实现setup和teardown操作，yield提供的参数为函数名称

• 与setup_module类似，pytest.fixture可作用于一个模块内的所有def和class。区别在于，必须将pytest.fixture()装饰的函数作为参数传递给用例。

• pytest.fixture()装饰的函数必须作为参数传递给用例吗？
  1）、将class中的smtp_ini都删除，class中的用例执行失败，def用例执行成功；
  2）、将class中test_send_text的smtp_ini保留，其余2个删除，class中的用例都执行成功？这是为什么呢？只有1个用力传入了参数，但所有用例都执行成功了。
  3）、将class和def中的smtp_ini都删除，用例全部执行失败。

• ps：用例内容与test_module.py的一致，就不粘代码了。

image.png

总结

4种方式的作用域：

• setup_method:仅作用于class用例集中的用例，置于class内,每个用例都会调用一次

• setup_function:作用于独立的def用例，不可作用于class内的用例

• setup_class:作用于class用例集中的用例，置于class内，只在class用例执行的开始执行setup_class,结束时执行teardown_class

• setup_module:作用于模块内的所有用例，置于class外，只在所以用例的开始执行setup_module,结束时执行teardown_module

• pytest.fixture():作用于模块内的所有用例，但需要传递装饰函数为参数，可置于class内或class外

  
  

博客：https://www.jianshu.com/u/39cef8a56bf9