How to extract values from response using extract() and JsonPath in Rest Assured?

Answer

Extracting Values in Rest Assured

Rest Assured provides multiple ways to extract data from API responses for use in subsequent requests (API chaining).

Method 1: extract().path() — Extract Single Field

Java

// Extract a single field directly
String userId = given()
                    .contentType(ContentType.JSON)
                    .body("{ \"name\": \"John\", \"job\": \"QA\" }")
                    .when()
                    .post("/api/users")
                    .then()
                    .statusCode(201)
                    .extract()
                    .path("id");

System.out.println("Created user ID: " + userId);

Method 2: extract().jsonPath() — Extract Multiple Fields

Java

Response response = given()
                        .when()
                        .get("/api/users/2")
                        .then()
                        .statusCode(200)
                        .extract()
                        .response();

JsonPath jsonPath = response.jsonPath();

String firstName = jsonPath.getString("data.first_name");
String lastName  = jsonPath.getString("data.last_name");
String email     = jsonPath.getString("data.email");
int    id        = jsonPath.getInt("data.id");

System.out.println(firstName + " " + lastName + " - " + email);

Method 3: extract().as() — Deserialize to POJO

Java

UserResponse user = given()
                        .when()
                        .get("/api/users/2")
                        .then()
                        .statusCode(200)
                        .extract()
                        .as(UserResponse.class); // deserialization

assertEquals(user.getData().getFirstName(), "Janet");

Method 4: extract() from Array

Java

// Extract list of all email addresses
List<String> emails = given()
                          .when()
                          .get("/api/users")
                          .then()
                          .extract()
                          .jsonPath()
                          .getList("data.email");

emails.forEach(System.out::println);

Method 5: Extract Response as String

Java

String responseBody = given()
                          .when()
                          .get("/api/users/1")
                          .then()
                          .extract()
                          .asString();

System.out.println(responseBody);

Common JsonPath Expressions

Expression	Gets
`"name"`	Top-level "name" field
`"data.email"`	Nested "email" inside "data"
`"data[0].id"`	First item in "data" array
`"data.findAll { it.id > 3 }.email"`	Filter array and get emails
`"data.size()"`	Array length