关于接口自动化

本文主要介绍如何用Java针对Restful web service 做接口自动化测试（数据驱动），相比UI自动化，接口自动化稳定性可靠性高，实施难易程度低，做自动化性价比高。所用到的工具或类库有 TestNG, Apache POI, Jayway rest-assured，Skyscreamer - JSONassert。

简介：

思想是数据驱动测试，用Excel来管理数据，‘Input’ Sheet中存放输入数据，读取数据后拼成request 调用service, 拿到response后写入 ‘Output’ Sheet 即实际结果, ‘Baseline’为基线（期望结果）用来和实际结果对比的，‘Comparison’ Sheet里存放的是对比结果不一致的记录，‘Result’ Sheet 是一个简单的结果报告。

Maven工程目录结构：

详细介绍

核心就一个测试类HTTPReqGenTest.java 由四部分组成

@BeforeTest  读取Excel (WorkBook) 的 ‘Input’ 和 ‘Baseline’ sheet

并且新建‘Output’, ‘Comparison’, ‘Result’ 三个空sheet

读取http_request_template.txt 内容转成string

@DataProvider (name = "WorkBookData")

TestNG的DataProvider, 首先用DataReader构造函数，读取Excel中Input的数据，放入HashMap<String, RecordHandler>, Map的key值就是test case的ID，value是RecordHandler对象，此对象中一个重要的成员属性就是input sheet里面 column和value 的键值对，遍历Map将test case ID 与 test case的value 即input sheet前两列的值放入List<Object[]> ，最后返回List的迭代器iterator (为了循环调用@Test方法)

@Test (dataProvider = "WorkBookData", description = "ReqGenTest")

测试方法，由DataProvider提供数据，首先根据ID去取myInputData里的RecordHandler， 由它和template 去生成request, 然后执行request 返回response，这些工作都是由HTTPReqGen.java这个类完成的，借助com.jayway.restassured， 返回的response是一个JSON体，通过org.skyscreamer.jsonassert.JSONCompare 与Baseline中事先填好的期望结果（同样也是JSON格式）进行比较， 根据结果是Pass还是Fail, 都会相应的往Excel里的相应Sheet写结果。

@AfterTest

写入统计的一些数据

关闭文件流

实现代码：

HTTPReqGenTest.java

package com.demo.qa.rest_api_test;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.Charset;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.apache.commons.io.IOUtils;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.json.JSONException;
import org.skyscreamer.jsonassert.JSONCompare;
import org.skyscreamer.jsonassert.JSONCompareMode;
import org.skyscreamer.jsonassert.JSONCompareResult;
import org.testng.Assert;
import org.testng.ITest;
import org.testng.ITestContext;
import org.testng.annotations.AfterTest;
import org.testng.annotations.BeforeTest;
import org.testng.annotations.DataProvider;
import org.testng.annotations.Parameters;
import org.testng.annotations.Test;

import com.demo.qa.utils.DataReader;
import com.demo.qa.utils.DataWriter;
import com.demo.qa.utils.HTTPReqGen;
import com.demo.qa.utils.RecordHandler;
import com.demo.qa.utils.SheetUtils;
import com.demo.qa.utils.Utils;
import com.jayway.restassured.response.Response;

public class HTTPReqGenTest implements ITest {

    private Response response;
    private DataReader myInputData;
    private DataReader myBaselineData;
    private String template;

    public String getTestName() {
        return "API Test";
    }

    String filePath = "";

    XSSFWorkbook wb = null;
    XSSFSheet inputSheet = null;
    XSSFSheet baselineSheet = null;
    XSSFSheet outputSheet = null;
    XSSFSheet comparsionSheet = null;
    XSSFSheet resultSheet = null;

    private double totalcase = 0;
    private double failedcase = 0;
    private String startTime = "";
    private String endTime = "";

    @BeforeTest
    @Parameters("workBook")
    public void setup(String path) {
        filePath = path;
        try {
            wb = new XSSFWorkbook(new FileInputStream(filePath));
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        inputSheet = wb.getSheet("Input");
        baselineSheet = wb.getSheet("Baseline");

        SheetUtils.removeSheetByName(wb, "Output");
        SheetUtils.removeSheetByName(wb, "Comparison");
        SheetUtils.removeSheetByName(wb, "Result");
        outputSheet = wb.createSheet("Output");
        comparsionSheet = wb.createSheet("Comparison");
        resultSheet = wb.createSheet("Result");

        try {
            InputStream is = HTTPReqGenTest.class.getClassLoader().getResourceAsStream("http_request_template.txt");
            template = IOUtils.toString(is, Charset.defaultCharset());
        } catch (Exception e) {
            Assert.fail("Problem fetching data from input file:" + e.getMessage());
        }

        SimpleDateFormat sf=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        startTime = sf.format(new Date());
    }

    @DataProvider(name = "WorkBookData")
    protected Iterator<Object[]> testProvider(ITestContext context) {

        List<Object[]> test_IDs = new ArrayList<Object[]>();

            myInputData = new DataReader(inputSheet, true, true, 0);
            Map<String, RecordHandler> myInput = myInputData.get_map();

            // sort map in order so that test cases ran in a fixed order
            Map<String, RecordHandler> sortmap = Utils.sortmap(myInput);

            for (Map.Entry<String, RecordHandler> entry : sortmap.entrySet()) {
                String test_ID = entry.getKey();
                String test_case = entry.getValue().get("TestCase");
                if (!test_ID.equals("") && !test_case.equals("")) {
                    test_IDs.add(new Object[] { test_ID, test_case });
                }
                totalcase++;
            }

            myBaselineData = new DataReader(baselineSheet, true, true, 0);

        return test_IDs.iterator();
    }

    @Test(dataProvider = "WorkBookData", description = "ReqGenTest")
    public void api_test(String ID, String test_case) {

        HTTPReqGen myReqGen = new HTTPReqGen();

        try {
            myReqGen.generate_request(template, myInputData.get_record(ID));
            response = myReqGen.perform_request();
        } catch (Exception e) {
            Assert.fail("Problem using HTTPRequestGenerator to generate response: " + e.getMessage());
        }

        String baseline_message = myBaselineData.get_record(ID).get("Response");

        if (response.statusCode() == 200)
            try {
                DataWriter.writeData(outputSheet, response.asString(), ID, test_case);

                JSONCompareResult result = JSONCompare.compareJSON(baseline_message, response.asString(), JSONCompareMode.NON_EXTENSIBLE);
                if (!result.passed()) {
                    DataWriter.writeData(comparsionSheet, result, ID, test_case);
                    DataWriter.writeData(resultSheet, "false", ID, test_case, 0);
                    DataWriter.writeData(outputSheet);
                    failedcase++;
                } else {
                    DataWriter.writeData(resultSheet, "true", ID, test_case, 0);
                }
            } catch (JSONException e) {
                DataWriter.writeData(comparsionSheet, "", "Problem to assert Response and baseline messages: "+e.getMessage(), ID, test_case);
                DataWriter.writeData(resultSheet, "error", ID, test_case, 0);
                failedcase++;
                Assert.fail("Problem to assert Response and baseline messages: " + e.getMessage());
            }
        else {
            DataWriter.writeData(outputSheet, response.statusLine(), ID, test_case);

            if (baseline_message.equals(response.statusLine())) {
                DataWriter.writeData(resultSheet, "true", ID, test_case, 0);
            } else {
                DataWriter.writeData(comparsionSheet, baseline_message, response.statusLine(), ID, test_case);
                DataWriter.writeData(resultSheet, "false", ID, test_case, 0);
                DataWriter.writeData(outputSheet);
                failedcase++;
            }
        }
    }

    @AfterTest
    public void teardown() {
        SimpleDateFormat sf=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        endTime = sf.format(new Date());
        DataWriter.writeData(resultSheet, totalcase, failedcase, startTime, endTime);

        try {
            FileOutputStream fileOutputStream = new FileOutputStream(filePath);
            wb.write(fileOutputStream);
            fileOutputStream.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

代码略了

运行是通过TestNG的xml文件来执行的， 里面配置了Parameter “workBook” 的路径

TestNG的运行结果都是Pass, 但事实上里面有case是Fail的，我只是借助TestNG来运行，我并没有在@Test方法里加断言Assert, 所以这里不会Fail, 我的目的是完全用Excel来管理维护测试数据以及测试结果，做到数据脚本完全分离。

当然 你也可以把maven工程打成一个可执行jar来运行,不过需要增加一个main函数作为入口，xml测试文件通过参数传递进去，另外还需要在pom里配置一些插件，像maven-jar-plugin。

如果你还需要做back-end DB check，你可以在Input里再增加几列，你要查询的表，字段，Baseline里也相应的加上期望结果，这里就不再赘述了。