简单实现接口自动化测试(基于python+unittest)

简介

本文通过从Postman获取基本的接口测试Code简单的接口测试入手，一步步调整优化接口调用，以及增加基本的结果判断，讲解Python自带的Unittest框架调用，期望各位可以通过本文对接口自动化测试有一个大致的了解。

引言

为什么要做接口自动化测试?

在当前互联网产品迭代频繁的背景下，回归测试的时间越来越少，很难在每个迭代都对所有功能做完整回归。但接口自动化测试因其实现简单、维护成本低，容易提高覆盖率等特点，越来越受重视。

为什么要自己写框架呢?

使用Postman调试通过过直接可以获取接口测试的基本代码，结合使用requets + unittest很容易实现接口自动化测试的封装，而且requests的api已经非常人性化，非常简单，但通过封装以后（特别是针对公司内特定接口），可以进一步提高脚本编写效率。

一个现有的简单接口例子

下面使用requests + unittest测试一个查询接口

接口信息如下

请求信息:

Method：POST

URL：api/match/image/getjson

Request：

{
"category": "image",
"offset": "0",
"limit": "30",
"sourceId": "0",
"metaTitle": "",
"metaId": "0",
"classify": "unclassify",
"startTime": "",
"endTime": "",
"createStart": "",
"createEnd": "",
"sourceType": "",
"isTracking": "true",
"metaGroup": "",
"companyId": "0",
"lastDays": "1",
"author": ""
}

Response示例：

{
"timestamp" : xxx,
"errorMsg" : "",
"data" : {
"config" : xxx
}

Postman测试方法见截图：

测试思路

1.获取Postman原始脚本

2.使用requests库模拟发送HTTP请求**

3.对原始脚本进行基础改造**

4.使用python标准库里unittest写测试case**

原始脚本实现

未优化

该代码只是简单的一次调用，而且返回的结果太多，很多返回信息暂时没用，示例代码如下

import requestsurl = "http://cpright.xinhua-news.cn/api/match/image/getjson"querystring = {"category":"image","offset":"0","limit":"30","sourceId":"0","metaTitle":"","metaId":"0","classify":"unclassify","startTime":"","endTime":"","createStart":"","createEnd":"","sourceType":"","isTracking":"true","metaGroup":"","companyId":"0","lastDays":"1","author":""} headers = { 'cache-control': "no-cache", 'postman-token': "e97a99b0-424b-b2a5-7602-22cd50223c15" } response = requests.request("POST", url, headers=headers, params=querystring) print(response.text)

优化第一版

调整代码结构，输出结果Json出来，获取需要验证的response.status_code，以及获取结果校验需要用到的results['total']

#!/usr/bin/env python
#coding: utf-8
'''
unittest merchant backgroud interface
@author: zhang_jin
@version: 1.0
@see:http://www.python-requests.org/en/master/
'''import unittest
import json import traceback import requests url = "http://cpright.xinhua-news.cn/api/match/image/getjson" querystring = { "category": "image", "offset": "0", "limit": "30", "sourceId": "0", "metaTitle": "", "metaId": "0", "classify": "unclassify", "startTime": "", "endTime": "", "createStart": "", "createEnd": "", "sourceType": "", "isTracking": "true", "metaGroup": "", "companyId": "0", "lastDays": "1", "author": "" } headers = { 'cache-control': "no-cache", 'postman-token': "e97a99b0-424b-b2a5-7602-22cd50223c15" } #Post接口调用 response = requests.request("POST", url, headers=headers, params=querystring) #对返回结果进行转义成json串 results = json.loads(response.text) #获取http请求的status_code print "Http code:",response.status_code #获取结果中的total的值 print results['total'] #print(response.text)

优化第二版

接口调用异常处理，增加try，except处理，对于返回response.status_code，返回200进行结果比对，不是200数据异常信息。

#!/usr/bin/env python
#coding: utf-8
'''
unittest merchant backgroud interface
@author: zhang_jin
@version: 1.0
@see:http://www.python-requests.org/en/master/
'''import json
import traceback import requests url = "http://cpright.xinhua-news.cn/api/match/image/getjson" querystring = { "category": "image", "offset": "0", "limit": "30", "sourceId": "0", "metaTitle": "", "metaId": "0", "classify": "unclassify", "startTime": "", "endTime": "", "createStart": "", "createEnd": "", "sourceType": "", "isTracking": "true", "metaGroup": "", "companyId": "0", "lastDays": "1", "author": "" } headers = { 'cache-control': "no-cache", 'postman-token': "e97a99b0-424b-b2a5-7602-22cd50223c15" } try: #Post接口调用 response = requests.request("POST", url, headers=headers, params=querystring) #对http返回值进行判断，对于200做基本校验 if response.status_code == 200: results = json.loads(response.text) if results['total'] == 191: print "Success" else: print "Fail" print results['total'] else: #对于http返回非200的code，输出相应的code raise Exception("http error info:%s" %response.status_code) except: traceback.print_exc()

优化第三版

1.该版本改动较大，引入config文件，单独封装结果校验模块，引入unittest模块，实现接口自动调用，并增加log处理模块；
2.对不同Post请求结果进行封装，不同接口分开调用；
3.测试用例的结果进行统计并最终输出

#!/usr/bin/env python
#coding: utf-8
'''
unittest interface
@author: zhang_jin
@version: 1.0
@see:http://www.python-requests.org/en/master/
'''import unittest
import json import traceback import requests import time import result_statistics import config as cf from com_logger import match_Logger class MyTestSuite(unittest.TestCase): """docstring for MyTestSuite""" #@classmethod def sedUp(self): print "start..." #图片匹配统计 def test_image_match_001(self): url = cf.URL1 querystring = { "category": "image", "offset": "0", "limit": "30", "sourceId": "0", "metaTitle": "", "metaId": "0", "classify": "unclassify", "startTime": "", "endTime": "", "createStart": "", "createEnd": "", "sourceType": "", "isTracking": "true", "metaGroup": "", "companyId": "0", "lastDays": "1", "author": "" } headers = { 'cache-control': "no-cache", 'postman-token': "545a2e40-b120-2096-960c-54875be347be" } response = requests.request("POST", url, headers=headers, params=querystring) if response.status_code == 200: response.encoding = response.apparent_encoding results = json.loads(response.text) #预期结果与实际结果校验，调用result_statistics模块 result_statistics.test_result(results,196) else: print "http error info:%s" %response.status_code #match_Logger.info("start image_query22222") #self.assertEqual(results['total'], 888) ''' try: self.assertEqual(results['total'], 888) except: match_Logger.error(traceback.format_exc()) #print results['total'] ''' #文字匹配数据统计 def test_text_match_001(self): text_url = cf.URL2 querystring = { "category": "text", "offset": "0", "limit": "30", "sourceId": "0", "metaTitle": "", "metaId": "0", "startTime": "2017-04-14", "endTime": "2017-04-15", "createStart": "", "createEnd": "", "sourceType": "", "isTracking": "true", "metaGroup": "", "companyId": "0", "lastDays": "0", "author": "", "content": "" } headers = { 'cache-control': "no-cache", 'postman-token': "ef3c29d8-1c88-062a-76d9-f2fbebf2536c" } response = requests.request("POST", text_url, headers=headers, params=querystring) if response.status_code == 200: response.encoding = response.apparent_encoding results = json.loads(response.text) #预期结果与实际结果校验，调用result_statistics模块 result_statistics.test_result(results,190) else: print "http error info:%s" %response.status_code #print(response.text) def tearDown(self): pass if __name__ == '__main__': #image_match_Logger = ALogger('image_match', log_level='INFO') #构造测试集合 suite=unittest.TestSuite() suite.addTest(MyTestSuite("test_image_match_001")) suite.addTest(MyTestSuite("test_text_match_001")) #执行测试 runner = unittest.TextTestRunner() runner.run(suite) print "success case:",result_statistics.num_success print "fail case:",result_statistics.num_fail #unittest.main()

最终输出日志信息

Zj-Mac:unittest lazybone$ python image_test_3.py
测试结果：通过.测试结果：不通过
错误信息： 期望返回值:190 实际返回值:4522.
----------------------------------------------------------------------
Ran 2 tests in 0.889s OK success case: 1 fail case: 1

后续改进建议

1.unittest输出报告也可以推荐使用HTMLTestRunner（我目前是对结果统计进行了封装）

2.接口的继续封装，参数化，模块化

3.unittest单元测试框架实现参数化调用第三方模块引用（nose-parameterized）

4.持续集成运行环境、定时任务、触发运行、邮件发送等一系列功能均可以在Jenkins上实现。