接口自动化测试 - RobotFramework RESTinstance

robot

1. 介绍

RESTinstance库是用来测试RESTful风格API接口的robot framework测试库。不同于RequestsLibrary库，RESTinstance库有如下一些优势。

rest

2. 优势

• RESTinstance基于Robot Framework的编程语言无关性，干净和简洁的语法来进行API测试。
• 使用JSON Schema来验证JSON语义，指导用户基于属性来编写API测试用例。
• 自动生成requests和responses的JSON Schema，通过测试Schema会变得更加精确。

详细的优势信息请查看链接

3. 安装

提供了几种安装方式，你可以选择最适合的一种。

3.1 python库安装

pypi

在Python 3.x或者2.7版本，可以通过安装或者升级命令来安装：

pip install --upgrade RESTinstance

3.2 Docker镜像方式

docker

RESTinstance Docker镜像包含了python3.6运行环境和最新的robot framework版本：

docker pull asyrjasalo/restinstance
docker run --rm -ti --env HOST_UID=$(id -u) --env HOST_GID=$(id -g) \
  --env HTTP_PROXY --env HTTPS_PROXY --network host \
  --volume "$PWD/tests":/home/robot/tests \
  --volume "$PWD/results":/home/robot/results \
  asyrjasalo/restinstance tests

4. 使用

4.1 快速启动

建议：用Robot Framework运行下面的例子README.rst

*** Settings ***
Library         REST    https://jsonplaceholder.typicode.com
Documentation   Test data can be read from variables and files.
...             Both JSON and Python type systems are supported for inputs.
...             Every request creates a so-called instance. Can be `Output`.
...             Most keywords are effective only for the last instance.
...             Initial schemas are autogenerated for request and response.
...             You can make them more detailed by using assertion keywords.
...             The assertion keywords correspond to the JSON types.
...             They take in either path to the property or a JSONPath query.
...             Using (enum) values in tests optional. Only type is required.
...             All the JSON Schema validation keywords are also supported.
...             Thus, there is no need to write any own validation logic.
...             Not a long path from schemas to full Swagger/OpenAPI specs.
...             The persistence of the created instances is the test suite.
...             Use keyword `Rest instances` to output the created instances.


*** Variables ***
${json}         { "id": 11, "name": "Gil Alexander" }
&{dict}         name=Julie Langford


*** Test Cases ***
GET an existing user, notice how the schema gets more accurate
    GET         /users/1                  # this creates a new instance
    Output      schema response body
    Object      response body             # values are fully optional
    Integer     response body id          1
    String      response body name        Leanne Graham
    [Teardown]  Output                    # note the updated response schema

GET existing users, use JSONPath for very short but powerful queries
    GET         /users?_limit=5           # further assertions are to this
    Array       response body
    Integer     $[0].id                   1           # first id is 1
    String      $[0]..lat                 -37.3159    # any matching child
    Integer     $..id                     maximum=5   # multiple matches
    [Teardown]  Output  $[*].email        # outputs all emails as an array

POST with valid params to create a new user, can be output to a file
    POST        /users                    ${json}
    Integer     response status           201
    [Teardown]  Output  response body     ${OUTPUTDIR}/new_user.demo.json

PUT with valid params to update the existing user, values matter here
    PUT         /users/2                  { "isCoding": true }
    Boolean     response body isCoding    true
    PUT         /users/2                  { "sleep": null }
    Null        response body sleep
    PUT         /users/2                  { "pockets": "", "money": 0.02 }
    String      response body pockets     ${EMPTY}
    Number      response body money       0.02
    Missing     response body moving      # fails if property moving exists

PATCH with valid params, reusing response properties as a new payload
    &{res}=     GET   /users/3
    String      $.name                    Clementine Bauch
    PATCH       /users/4                  { "name": "${res.body['name']}" }
    String      $.name                    Clementine Bauch
    PATCH       /users/5                  ${dict}
    String      $.name                    ${dict.name}

DELETE the existing successfully, save the history of all requests
    DELETE      /users/6                  # status can be any of the below
    Integer     response status           200    202     204
    Rest instances  ${OUTPUTDIR}/all.demo.json  # all the instances so far

5. 对比

我们来分别用RequestsLibrary和RESTinstance来编写接口自动化测试用例，这样就可以直观地进行对比。
我们假设http://echo.jsontest.com/framework/robot-framework/api/rest会返回如下值：

{
   "api": "rest",
   "framework": "robot-framework"
}

RequestsLibary实现

*** settings ***
Library  Collections
Library  requests
 
*** test cases ***
simpleRequest
    ${result} =  get  http://echo.jsontest.com/framework/robot-framework/api/rest
    Should Be Equal  ${result.status_code}  ${200}
    ${json} =  Set Variable  ${result.json()}
    ${framework} =  Get From Dictionary  ${json}  framework
    Should Be Equal  ${framework}  robot-framework
    ${api} =  Get From Dictionary  ${json}  api
    Should Be Equal  ${api}  rest

RESTinstance实现

*** settings ***
Library  REST  http://echo.jsontest.com
 
*** test cases ***
simpleRequest
    GET  /framework/robot-framework/api/rest
    Object  response body
    String  response body api  rest  
    String  response body framework  robot-framework

从以上两个测试用例中，我们就可以很容易看出来哪个库更方便使用了。

6. 结论

RESTinstance库比RequestsLibrary库更适合RESTful风格的HTTP API测试。