When testing RESTful APIs, handling HTTP query parameters is a common requirement. Query parameters allow you to pass additional data in the URL, influencing the behavior of the API. REST Assured, a popular Java library for testing REST APIs, makes handling query parameters simple and efficient.
In this blog, we will explore how to use REST Assured to handle query parameters in various scenarios, with practical examples.
What Are Query Parameters?
Query parameters are appended to the URL after a ? and are typically used to filter or customize API responses. For example:
https://api.example.com/users?age=25&gender=male
Here, age and gender are query parameters, and their respective values are 25 and male.
Using Query Parameters in REST Assured
REST Assured provides methods to include query parameters when making requests. The two commonly used methods are:
queryParam()– Adds a single query parameter.queryParams()– Adds multiple query parameters in one call.
Setting Up REST Assured
To start, add the REST Assured dependency to your pom.xml if you're using Maven:
<dependency>
<groupId>io.rest-assured</groupId>
<artifactId>rest-assured</artifactId>
<version>5.3.0</version>
<scope>test</scope>
</dependency>
1. Single Query Parameter
You can use the queryParam() method to pass a single query parameter to your API request.
import static io.restassured.RestAssured.*;
import io.restassured.response.Response;
public class QueryParamExample {
public static void main(String[] args) {
Response response = given()
.baseUri("https://api.example.com")
.queryParam("age", 25) // Adding a single query parameter
.when()
.get("/users");
response.prettyPrint();
}
}
2. Multiple Query Parameters
To add multiple query parameters, use the queryParams() method or chain multiple queryParam() calls.
Using queryParams():
queryParam() Calls:3. Dynamic Query Parameters
You can handle dynamic query parameters by passing values at runtime, such as reading them from variables or external files.
String age = "30";
String gender = "female";
given()
.baseUri("https://api.example.com")
.queryParam("age", age)
.queryParam("gender", gender)
.when()
.get("/users")
.then()
.statusCode(200)
.log().all();
4. Query Parameters with Special Characters
When a query parameter value contains special characters (e.g., spaces, ampersands), REST Assured handles encoding for you. For example:
given()
.baseUri("https://api.example.com")
.queryParam("search", "SDET & QA") // Special character: '&'
.when()
.get("/jobs")
.then()
.statusCode(200)
.log().all();
5. Combining Path and Query Parameters
REST Assured also allows combining path parameters and query parameters in the same request.
given()
.baseUri("https://api.example.com")
.pathParam("userId", 123)
.queryParam("details", "full")
.when()
.get("/users/{userId}")
.then()
.statusCode(200)
.log().all();
Validating Query Parameter Responses
You can validate query parameter responses using REST Assured’s assertion methods:
given()
.baseUri("https://api.example.com")
.queryParam("age", 25)
.queryParam("gender", "male")
.when()
.get("/users")
.then()
.statusCode(200)
.body("size()", greaterThan(0)) // Assert response has users
.body("users[0].age", equalTo(25)) // Validate the first user's age
.log().all();
