JUnit email and OTP testing
Use MailSlurp in JUnit suites to create inboxes, wait for verification emails, and extract OTP codes.
MailSlurp integrates cleanly with JUnit when the Java test suite owns both the app action and the email assertion. The usual pattern is to create an inbox with the Java SDK, submit the generated address in the workflow under test, wait for the latest email, and extract a code or link from the body.
Install
Maven:
<dependency>
<groupId>com.mailslurp</groupId>
<artifactId>mailslurp-client-java</artifactId>
<version>LATEST</version>
<type>pom</type>
</dependency>
Gradle:
dependencies {
implementation("com.mailslurp:mailslurp-client-java")
}
Create an inbox with the Java SDK
InboxDto inbox = inboxControllerApi.createInboxWithDefaults().execute();
// verify inbox
assertEquals(inbox.getEmailAddress().contains("@mailslurp"), true);
assertNotNull(inbox.getId());
Example JUnit OTP flow
import com.mailslurp.apis.InboxControllerApi;
import com.mailslurp.apis.WaitForControllerApi;
import com.mailslurp.clients.ApiClient;
import com.mailslurp.clients.Configuration;
import com.mailslurp.models.Email;
import com.mailslurp.models.InboxDto;
import org.junit.jupiter.api.Test;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import static org.junit.jupiter.api.Assertions.*;
class SignupOtpTest {
@Test
void completesEmailVerification() throws Exception {
ApiClient defaultClient = Configuration.getDefaultApiClient();
defaultClient.setApiKey(System.getenv("API_KEY"));
defaultClient.setConnectTimeout(120_000);
defaultClient.setReadTimeout(120_000);
defaultClient.setWriteTimeout(120_000);
InboxControllerApi inboxControllerApi = new InboxControllerApi(defaultClient);
WaitForControllerApi waitForControllerApi = new WaitForControllerApi(defaultClient);
InboxDto inbox = inboxControllerApi.createInboxWithDefaults().execute();
// Submit inbox.getEmailAddress() in the app under test here.
Email email =
waitForControllerApi
.waitForLatestEmail()
.inboxId(inbox.getId())
.timeout(120_000L)
.unreadOnly(true)
.execute();
Matcher matcher = Pattern
.compile("(?:verification code|OTP|code)[:\\\\s-]*(\\\\d{6})")
.matcher(email.getBody());
assertTrue(matcher.find());
assertNotNull(matcher.group(1));
}
}
Example projects
Java Gradle Junit5java example repository:
java-gradle-junit5
Java Maven Junit4java example repository: java-maven-junit4