Postman使用手册4——API test
一、Pre Request Scripts
Postman v0.10+ 版本支持pre-request scripts。
prerequest script.pngpre-request scripts是一个关联了收藏夹内request,并且在发送request之前执行的代码片段。这对于在request header中包含时间戳或者在URL参数中发送一个随机字符串都是非常有用的。
例如:如果要在request的header中包含一个时间戳,你可以设置一个环境变量由一个函数返回他的值。
postman.setEnvironmentVariable('timestampHeader',new Date());
你可以在header中使 timestampHeader 变量,当request发送的时候,你的pre-request script将被执行,这个timestampHeader 变量的值将会替换{{timestampHeader}}。
注意:我们设置的环境对使用的环境变量必须是有效的。
二、Writing Tests
1.基本结构
![Uploading prerequest script_871640.png . . .]
Basic structure.png
Postman给了你一个环境让你能够为每个request编写、执行你的test,而不用担心任何额外的设置。
一个Postman的test本质上是JavaScript的代码可以用来为一些特殊的test设置值。你可以在对象中设置一个描述性的键作为一个元素,然后声明他如果是true或false。
tests[“Body contains user_id”] = responseBody.has(“user_id”)
这回核对body中是否包含了user_id这个字符串。如果你需要,你可以增加更多的键,这取决于你要用test做多少的事情。
test被保存为收藏夹request的一部分,这对于后端或前端的工程师来确保API运行的正常都是非常有意义的。
2.SNIPPETS
在写test的时候这里有些事情需要注意,Postman尝试使得列出常用的片段更简单。你可以选择你想添加的片段,然后适当的代码将被添加到test的编辑器中。这是一个很好的方法来快速的构建test
3.查看结果
view result.png
Postman在你执行一个request的时候执行test,当然你可以选择不考虑test。结果被显示在一个tab里,并在头部显示多少test通过了测试。你设置在test中的变量将会被列在这里。如果值是true,这个test就会通过。你可以保持test tab活动直到你确保所有的test执行完。
三、Testing Sandbox
Postman的sandbox是一个JavaScript的执行环境,这使得你能够为request写pre-request scripts和test scripts 。不论你写的代码是pre-request scripts还是test script都会在sandbox中执行。
1.常用的库和工具
-
Lodash:
JS utility library -
jQuery (Deprecated):
Cross-platform JavaScript library. This will be removed in future versions of the sandbox. -
BackboneJS (Deprecated):
Provides simple models, views, and collections. This will be removed in future versions of the sandbox. -
SugarJS:
Extends native JS objects with useful methods -
tv4 JSON schema validator:
Validates JSON objects against v4 of the json-schema draft -
CryptoJS:
standard and secure cryptographic algorithms. Supported algorithms: AES, DES, EvpKDF, HMAC-MD5, HMAC-SHA1/3/256/512, MD5, PBKDF2, Rabbit, SHA1/3/224/256/512, TripleDES -
xml2Json(xmlString)
:
This function behaves the same in Newman and Postman -
xmlToJson(xmlString)
(Deprecated):
This function does NOT behave the same in Newman and Postman -
postman.getResponseHeader(headerName)
(Test-only):
returns the response header with name "headerName", if it exists. Returns null if no such header exists. Note: According to W3C specifications, header names are case-insensitive. This method takes care of this.
postman.getResponseHeader("Content-type") and postman.getResponseHeader("content-Type") will return the same value.
2.环境和全局变量
-
postman.setEnvironmentVariable(variableName, variableValue)
: Sets an environment variable "variableName", and assigns the string "variableValue" to it. You must have an environment selected for this method to work. Note: Only strings can be stored. Storing other types of data will result in unexpected behavior. -
postman.setGlobalVariable(variableName, variableValue)
:
Sets a global variable "variableName", and assigns the string "variableValue" to it. Note: Only strings can be stored. Storing other types of data will result in unexpected behavior. -
postman.clearEnvironmentVariable(variableName)
:
Clears the environment variable named "variableName". You must have an environment selected for this method to work. -
postman.clearGlobalVariable(variableName)
:
Clears the global variable named "variableName". -
postman.clearEnvironmentVariables()
:
Clears all environment variables. You must have an environment selected for this method to work. -
postman.clearGlobalVariables()
:
Clears all global variables. -
environment
:
A dictionary of variables in the current environment. Use environment["foo"]
to access the value of the "foo" environment variable. -
globals
:
A dictionary of global variables. Useglobals["bar"]
to access the value of the "bar" global variable.
3.动态变量
Postman也有一些动态变量,你可以用在你的request中。这个现在主要还是在实现阶段,更多的功能以后被被添加进来。注意:动态变量不可以用于SandBox中,你只能在request的URL、headers、body中以放在双花括号中间的形式使用。
-
{{$guid}}: Adds a v4 style guid
-
{{$timestamp}}: Adds the current timestamp.
-
{{$randomInt}}: Adds a random integer between 0 and 1000
4. Cookies
+** responseCookies {array} **(Postman-only):
Gets all cookies set for the domain. You will need to enable the Interceptor for this to work.
-
postman.getResponseCookie(cookieName)(Postman-only):
Gets the response cookie with the given name. You will need to enable the interceptor for this to work. Check out the blog post.
5.Request/response相关属性
-
request {object}:
Postman makes the request object available to you while writing scripts. This object is read-only. Changing properties of this object will have no effect. Note: Variables will NOT be resolved in the request object. The request object is composed of the following:-
data {object}:
this is a dictionary of form data for the request. (request.data["key"]=="value") -
headers {object}:
this is a dictionary of headers for the request (request.headers["key"]=="value") -
method {string}:
GET/POST/PUT etc. -
url {string}:
the url for the request.
-
-
responseHeaders {object}(Test-only)(Deprecated):
This is a map of the response headers. This is case-sensitive, and should not be used. Check thepostman.getResponseHeader()
method listed above. -
responseBody {string}(Test-only):
A string containing the raw response body text. You can use this as an input to JSON.parse, or xml2Json. -
responseTime {number}(Test-only):
The response time in milliseconds -
responseCode {object}(Test-only):
Contains three properties:-
code {number}:
The response code (200 for OK, 404 for Not Found etc) -
name {string}:
The status code text -
detail {string}:
An explanation of the response code
-
-
tests {object}(Test-only):
This object is for you to populate. Postman will treat each property of this object as a boolean test. -
iteration {number}:
Only available in the Collection Runner and Newman. Represents the current test run index. Starts from 0.
(Test-only): This object is only available in the test script section. Using this in a pre-request script will throw an error.
四、Testing 实例
我们来看一些Postman用于test的例子。这些例子中的大多数在Postman中是有效的,他们像一行JavaScript语句一样简答。在你的request中你可以有很多的test。
注意:test脚本在从服务器收到response后执行
1.设置环境变量:
postman.setEnvironmentVariable("key", "value");
2.设置全局变量:
postman.setGlobalVariable("key", "value");
3.检查response的body中是否包含字符串:
tests["Body matches string"] = responseBody.has("string_you_want_to_search");
4.把XML的body转换成JSON对象:
var jsonObject = xml2Json(responseBody);
5.检查response的body是都为一个字符串:
tests["Body is correct"] = responseBody === "response_body_string";
6.检查JSON的值:
var data = JSON.parse(responseBody);
tests["Your test name"] = data.value === 100;
7.内容类型存在(检查不区分大小写)
tests["Content-Type is present"] = postman.getResponseHeader("Content-Type"); //Note: the getResponseHeader() method returns the header value, if it exists.
8.内容类型存在(区分大小写):
tests["Content-Type is present"] = responseHeaders.hasOwnProperty("Content-Type");
9.response的响应时间小于200ms:
tests["Response time is less than 200ms"] = responseTime < 200;
10.状态码为200:
tests["Status code is 200"] = responseCode.code === 200;
11.Code name contains a string:
tests["Status code name has string"] = responseCode.name.has("Created");
12.成功的POST request状态码:
tests["Successful POST request"] = responseCode.code === 201 || responseCode.code === 202;
13.Use TinyValidator for JSON data
var schema = {
"items": {
"type": "boolean"
}
};
var data1 = [true, false];
var data2 = [true, 123];
console.log(tv4.error);
tests["Valid Data1"] = tv4.validate(data1, schema);
tests["Valid Data2"] = tv4.validate(data2, schema);
14.Sample data files
JSON files are composed of key/value pairs:
For CSV files, the top row needs to contain variable names
Postman 使用手册系列教程:
Postman软件安装
Postman使用手册1——导入导出和发送请求查看响应
Postman使用手册2——管理收藏
Postman使用手册3——环境变量
Postman使用手册4——API test