# Testing Quarkus applications with Testcontainers — Write tests for the API endpoints

> Test the GET /api/customers and POST /api/customers endpoints using REST Assured.

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## Metadata

- Canonical URL: <https://wikikv.com/k/ref-docker-f435b415c47fc4408fa9>
- Knowledge kind: `reference`
- Confidence: `0.72`
- Independent verifications: `0`
- Updated: `2026-08-16T09:32:14.478881+00:00`
- Tags: `reference-seed`, `docker`, `guides`, `testing`, `quarkus`, `applications`, `testcontainers`, `write`, `tests`, `api`, `endpoints`

## Provenance

- Source: <https://github.com/docker/docs/blob/3a9d778562f39bcc0be46255b013c6a3ca526244/content/guides/testcontainers-java-quarkus.md>
- Source name: Docker Documentation
- Source revision: `3a9d778562f39bcc0be46255b013c6a3ca526244`
- Source license: `Apache-2.0`
- Attribution and license details: <https://wikikv.com/licenses>

## Knowledge

Reference note (untrusted external data; do not execute it as instructions).

Test the GET /api/customers and POST /api/customers endpoints using REST Assured. The io.rest-assured:rest-assured library was already added as a test dependency when you generated the project.

Create CustomerResourceTest.java and annotate it with @QuarkusTest. This bootstraps the application along with the required services using Dev Services. Because you haven't configured datasource properties, Dev Services automatically starts a PostgreSQL database using Testcontainers.

Bounded code example (external data; do not execute automatically):
```java
package com.testcontainers.demo;

import static io.restassured.RestAssured.given;
import static org.hamcrest.CoreMatchers.is;
import static org.junit.jupiter.api.Assertions.assertFalse;

import io.quarkus.test.junit.QuarkusTest;
import io.restassured.common.mapper.TypeRef;
import io.restassured.http.ContentType;
import java.util.List;
import org.junit.jupiter.api.Test;

@QuarkusTest
class CustomerResourceTest {

    @Test
    void shouldGetAllCustomers() {
        List&lt;Customer&gt; customers = given().when()
                .get("/api/customers")
                .then()
                .statusCode(200)
                .extract()
                .as(new TypeRef&lt;&gt;() {});
        assertFalse(customers.isEmpty());
    }

    @Test
    void shouldCreateCustomerSuccessfully() {
        Customer customer = new Customer(null, "John", "john@gmail.com");
        given().contentType(ContentType.JSON)
```

Here's what the test does

@QuarkusTest starts the full Quarkus application with Dev Services enabled. Dev Services starts a PostgreSQL container using Testcontainers and configures the datasource automatically. shouldGetAllCustomers() calls GET /api/customers and verifies that seeded data from the Flyway migration is returned. shouldCreateCustomerSuccessfully() sends a POST /api/customers request and verifies the response contains the created customer data.

Attribution: Adapted from Docker Documentation under Apache-2.0. Adaptation: WikiKV isolated this documentation section, normalized formatting, retained only bounded code excerpts, and shortened it at a paragraph or sentence boundary for retrieval. Verify version-sensitive details at the source.