Answer
Authentication in Rest Assured
Rest Assured supports multiple authentication types through the .auth() method chain.
1. Basic Authentication
Java
Response resp = given()
.auth()
.basic("username", "password")
.when()
.get("https://reqres.in/api/users/2");
assertEquals(resp.getStatusCode(), 200);
2. Pre-emptive Authentication
Sends credentials with the FIRST request (without waiting for 401 challenge):
Java
Response resp1 = given()
.auth()
.preemptive()
.basic("username", "password")
.when()
.get("https://reqres.in/api/users/2");
3. Digest Authentication
Digest auth hashes credentials before sending:
Java
Response resp2 = given()
.auth()
.digest("username", "password")
.when()
.get("https://reqres.in/api/users/2");
4. OAuth Authentication
Java
Response resp3 = given()
.auth()
.oauth("consumerKey", "consumerSecret",
"accessToken", "secretToken")
.when()
.get("https://reqres.in/api/users/2");
5. OAuth2 Authentication
Java
Response resp4 = given()
.auth()
.oauth2("your-access-token")
.when()
.get("https://reqres.in/api/users/2");
6. Header-Based Authorization (OAuth2)
Java
Response resp5 = given()
.header("Authorization", "Bearer your-access-token")
.when()
.get("https://reqres.in/api/users/2");
Summary
| Auth Type | Method | When to Use |
|---|---|---|
| Basic | .auth().basic(u, p) | Simple username/password |
| Preemptive | .auth().preemptive().basic(u, p) | Avoid round-trip 401 challenge |
| Digest | .auth().digest(u, p) | Hashed credentials |
| OAuth 1.0 | .auth().oauth(...) | Legacy OAuth |
| OAuth 2.0 | .auth().oauth2(token) | Modern APIs with Bearer tokens |