Test scripts are run after a request is sent and a response has been received from the server.
Let’s look at some examples of Postman tests. Most of these are available as snippets inside Postman. You can have as many tests as you want for a request.
Setting an environment variable
pm.environment.set("variable_key", "variable_value");
Setting a nested object as an environment variable
var array = [1, 2, 3, 4];
pm.environment.set("array", JSON.stringify(array, null, 2));
var obj = { a: [1, 2, 3, 4], b: { c: 'val' } };
pm.environment.set("obj", JSON.stringify(obj));
Getting an environment variable
pm.environment.get("variable_key");
Getting an environment variable (whose value is a stringified object)
// These statements should be wrapped in a try-catch block if the data is coming from an unknown source.
var array = JSON.parse(pm.environment.get("array"));
var obj = JSON.parse(pm.environment.get("obj"));
Clear an environment variable
pm.environment.unset("variable_key");
Set a global variable
pm.globals.set("variable_key", "variable_value");
Get a global variable
pm.globals.get("variable_key");
Clear a global variable
pm.globals.unset("variable_key");
Get a variable
This function searches for the variable across globals and the active environment.
pm.variables.get("variable_key");
Check if response body contains a string
pm.test("Body matches string", function () {
pm.expect(pm.response.text()).to.include("string_you_want_to_search");
});
Check if response body is equal to a string
pm.test("Body is correct", function () {
pm.response.to.have.body("response_body_string");
});
Check for a JSON value
pm.test("Your test name", function () {
var jsonData = pm.response.json();
pm.expect(jsonData.value).to.eql(100);
});
Content-Type is present
pm.test("Content-Type is present", function () {
pm.response.to.have.header("Content-Type");
});
Response time is less than 200ms
pm.test("Response time is less than 200ms", function () {
pm.expect(pm.response.responseTime).to.be.below(200);
});
Status code is 200
pm.test("Status code is 200", function () {
pm.response.to.have.status(200);
});
Code name contains a string
pm.test("Status code name has string", function () {
pm.response.to.have.status("Created");
});
Successful POST request status code
pm.test("Successful POST request", function () {
pm.expect(pm.response.code).to.be.oneOf([201,202]);
});
Use TinyValidator for JSON data
var schema = {
"items": {
"type": "boolean"
}
};
var data1 = [true, false];
var data2 = [true, 123];
pm.test('Schema is valid', function() {
pm.expect(tv4.validate(data1, schema)).to.be.true;
pm.expect(tv4.validate(data2, schema)).to.be.true;
});
Decode base64 encoded data
var intermediate,
base64Content, // assume this has a base64 encoded value
rawContent = base64Content.slice('data:application/octet-stream;base64,'.length);
intermediate = CryptoJS.enc.Base64.parse(base64content); // CryptoJS is an inbuilt object, documented here: https://www.npmjs.com/package/crypto-js
pm.test('Contents are valid', function() {
pm.expect(CryptoJS.enc.Utf8.stringify(intermediate)).to.be.true; // a check for non-emptiness
});
Send an asynchronous request
This function is available as both a pre-request and test script.
pm.sendRequest("https://postman-echo.com/get", function (err, response) {
console.log(response.json());
});
Convert XML body to a JSON object
var jsonObject = xml2Json(responseBody);
JSON files are composed of key/value pairs.
For CSV files, the top row needs to contain variable names.
The older style of writing Postman tests relies on setting values for the special tests object. You can set a descriptive key for an element in the object and then say if it’s true or false. For example, tests["Body contains user_id"] = responsebody.has("user_id"); will check whether the response body contains the user_id string.
You can add as many keys as needed, depending on how many things you want to test for. Under the Tests tab under the response viewer, you can view your test results. The tab header shows how many tests passed, and the keys that you set in the tests variable are listed here. If the value evaluates to true, the test passed.
Setting an environment variable
postman.setEnvironmentVariable("key", "value");
Setting a nested object as an environment variable
var array = [1, 2, 3, 4];
postman.setEnvironmentVariable("array", JSON.stringify(array, null, 2));
var obj = { a: [1, 2, 3, 4], b: { c: 'val' } };
postman.setEnvironmentVariable("obj", JSON.stringify(obj));
Getting an environment variable
postman.getEnvironmentVariable("key");
Getting an environment variable (whose value is a stringified object)
// These statements should be wrapped in a try-catch block if the data is coming from an unknown source.
var array = JSON.parse(postman.getEnvironmentVariable("array"));
var obj = JSON.parse(postman.getEnvironmentVariable("obj"));
Clear an environment variable
postman.clearEnvironmentVariable("key");
Set a global variable
postman.setGlobalVariable("key", "value");
Get a global variable
postman.getGlobalVariable("key");
Clear a global variable
postman.clearGlobalVariable("key");
Check if response body contains a string
tests["Body matches string"] = responseBody.has("string_you_want_to_search");
Convert XML body to a JSON object
var jsonObject = xml2Json(responseBody);
Check if response body is equal to a string
tests["Body is correct"] = responseBody === "response_body_string";
Check for a JSON value
var data = JSON.parse(responseBody);
tests["Your test name"] = data.value === 100;
Content-Type is present (Case-insensitive checking)
tests["Content-Type is present"] = postman.getResponseHeader("Content-Type"); //Note: the getResponseHeader() method returns the header value, if it exists.
Content-Type is present (Case-sensitive)
tests["Content-Type is present"] = responseHeaders.hasOwnProperty("Content-Type");
Response time is less than 200ms
tests["Response time is less than 200ms"] = responseTime < 200;
Response time is within a specific range (lower bound inclusive, upper bound exclusive)
tests["Response time is acceptable"] = _.inRange(responseTime, 100, 1001); // _ is the inbuilt Lodash v3.10.1 object, documented at https://lodash.com/docs/3.10.1
Status code is 200
tests["Status code is 200"] = responseCode.code === 200;
Code name contains a string
tests["Status code name has string"] = responseCode.name.has("Created");
Successful POST request status code
tests["Successful POST request"] = responseCode.code === 201 || responseCode.code === 202;
Use TinyValidator for JSON data
var schema = {
"items": {
"type": "boolean"
}
};
var data1 = [true, false];
var data2 = [true, 123];
tests["Valid Data1"] = tv4.validate(data1, schema);
tests["Valid Data2"] = tv4.validate(data2, schema);
console.log("Validation failed: ", tv4.error);
Decode base64 encoded data
var intermediate,
base64Content, // assume this has a base64 encoded value
rawContent = base64Content.slice('data:application/octet-stream;base64,'.length);
intermediate = CryptoJS.enc.Base64.parse(base64content); // CryptoJS is an inbuilt object, documented here: https://www.npmjs.com/package/crypto-js
tests["Contents are valid"] = CryptoJS.enc.Utf8.stringify(intermediate); // a check for non-emptiness