Sixty lines of plumbing per endpoint and nobody reviews it

Problem Description

The inventory test module is written directly against the JDK HTTP client with JSON parsing by hand. Three endpoints cost us about a hundred lines, most of which is request construction and walking down a parsed tree to get at one value.

Two problems with it, both raised in the last retro:

Nobody can review it. In a pull request the reviewer sees a request being assembled at the top, a response being taken apart at the bottom, and has to hold the middle in their head to work out what is actually being asserted. Adding the fourth endpoint took a day, most of it spent copying and adapting the existing plumbing.

When it fails, the message is expected: <200> but was: <503> or java.lang.NullPointerException: Cannot invoke "JsonNode.asText()" because the return value of "JsonNode.get(String)" is null. Neither says which request, which field, or what came back.

There are also two different ways of getting at a nested value in the file already, because two people wrote two helpers a month apart, and every method signature carries throws Exception.

The module already has a client library on its dependency list - it was added last sprint for a spike that never landed - so you do not need to introduce anything new.

Output Specification

1. Rewrite the three tests so that each one reads as one thing: the request that goes out, the call, and the expectations on what comes back.
2. Get rid of the hand-written JSON navigation and the two competing helpers.
3. No throws clauses on the test methods.
4. Keep the same three behaviours and the same expected values - list them in your answer so a reviewer can confirm nothing was lost.
5. The credential must keep coming from the environment.

Out of scope: do not add dependencies beyond what pom.xml already declares, and do not change the endpoints or the request payloads.

Input Files

Extract the following files before beginning.

=============== FILE: src/test/java/com/example/inventory/StockLevelsIT.java =============== package com.example.inventory;

import com.fasterxml.jackson.databind.JsonNode; import com.fasterxml.jackson.databind.ObjectMapper; import org.junit.jupiter.api.DisplayName; import org.junit.jupiter.api.Test;

import java.net.URI; import java.net.http.HttpClient; import java.net.http.HttpRequest; import java.net.http.HttpResponse;

import static org.junit.jupiter.api.Assertions.assertEquals; import static org.junit.jupiter.api.Assertions.assertNotNull; import static org.junit.jupiter.api.Assertions.assertTrue;

class StockLevelsIT {

private static final String BASE = System.getProperty("api.baseURI", "http://localhost:8080"); private static final HttpClient CLIENT = HttpClient.newHttpClient(); private static final ObjectMapper MAPPER = new ObjectMapper();

private static HttpResponse get(String path) throws Exception { HttpRequest request = HttpRequest.newBuilder() .uri(URI.create(BASE + path)) .header("Accept", "application/json") .header("Authorization", "Bearer " + System.getenv("API_TOKEN")) .GET() .build(); return CLIENT.send(request, HttpResponse.BodyHandlers.ofString()); }

private static JsonNode firstItem(String body) throws Exception { return MAPPER.readTree(body).get("items").get(0); }

@Test @DisplayName("stock for a known sku") void stockForSku() throws Exception { HttpResponse response = get("/v1/stock/SKU-1001"); assertEquals(200, response.statusCode()); JsonNode body = MAPPER.readTree(response.body()); assertEquals("SKU-1001", body.get("sku").asText()); assertEquals("WH-BER", body.get("warehouse").asText()); assertTrue(body.get("on_hand").asInt() > 0); }

@Test @DisplayName("stock listing for a warehouse") void stockForWarehouse() throws Exception { HttpResponse response = get("/v1/stock?warehouse=WH-BER"); assertEquals(200, response.statusCode()); JsonNode first = firstItem(response.body()); assertTrue(first.get("sku").asText().matches("^SKU-\d{4}$")); assertTrue(MAPPER.readTree(response.body()).get("items").size() > 0); }

@Test @DisplayName("a reservation can be held against available stock") void reservesStock() throws Exception { HttpRequest request = HttpRequest.newBuilder() .uri(URI.create(BASE + "/v1/stock/SKU-1001/reservations")) .header("Accept", "application/json") .header("Content-Type", "application/json") .header("Authorization", "Bearer " + System.getenv("API_TOKEN")) .POST(HttpRequest.BodyPublishers.ofString("{"quantity":2,"order_id":"ORD-88"}")) .build(); HttpResponse response = CLIENT.send(request, HttpResponse.BodyHandlers.ofString()); assertEquals(201, response.statusCode()); JsonNode reservation = MAPPER.readTree(response.body()).path("reservation"); assertNotNull(reservation.get("reservation_id")); assertEquals("held", reservation.get("state").asText()); assertEquals(2, reservation.get("quantity").asInt()); } }

=============== FILE: pom.xml =============== 4.0.0 com.acme inventory-api-tests 2.0.0-SNAPSHOT

21 UTF-8 io.rest-assured rest-assured 6.0.0 test com.fasterxml.jackson.core jackson-databind 2.17.1 test org.junit.jupiter junit-jupiter 5.10.2 test maven-failsafe-plugin 3.2.5 integration-test verify