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Java One More Time With Feeling

API tests have all started failing

All of the tests in ApiTest.java are failing for me, even though I remember them working before.

Here is the error message I'm getting:

java.net.ConnectException: Connection refused (Connection refused)


java.lang.RuntimeException: Whoops!  Connection error

    at com.teamtreehouse.testing.ApiClient.request(ApiClient.java:42)
    at com.teamtreehouse.courses.model.ApiTest.addingCoursesReturnsCreatedStatus(ApiTest.java:63)

This is what my Api model looks like:

package com.teamtreehouse.courses.model;

import com.google.gson.Gson;
import com.teamtreehouse.courses.dao.CourseDao;
import com.teamtreehouse.courses.dao.Sql2oCourseDao;
import com.teamtreehouse.courses.exc.ApiError;
import org.sql2o.Sql2o;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

import static spark.Spark.*;

public class Api {
    public static void main(String[] args) {
        String dataSource = "jdbc:h2:~/reviews.db";

        //if arguments are provided for Port and Data Source, else use defaults
        if(args.length > 0) {
            //if two arguments are not specified, api was not used correctly
            if(args.length != 2) {
                System.out.println("java api <port> <datasource>");
            //setting the port
            //setting the dataSource (changing the default)
            dataSource = args[1];

        Sql2o sql2o = new Sql2o(
                String.format("%s;INIT=RUNSCRIPT from 'classpath:db/init.sql'", dataSource),
                "", "");
        CourseDao courseDao = new Sql2oCourseDao(sql2o);
        Gson gson = new Gson();

        //method for handling post requests:
        post("/courses", "application/json", (req, res) -> {
            //convert the body of the request (JSON) to a Course object and store it in a variable:
            Course course = gson.fromJson(req.body(), Course.class);
            return course;
        }, gson::toJson);

        //method for handling get requests:
        get("/courses", "application/json", (req, res) -> courseDao.findAll(), gson::toJson);

        //method for handling get requests:
        get("/courses/:id", "application/json", (req, res) -> {
            int id = Integer.parseInt(req.params("id"));
            Course course = courseDao.findById(id);
            if(course == null) {
                throw new ApiError(404, "Could not find course with id " + id);
            return course;
        }, gson::toJson);

        exception(ApiError.class, (exc, req, res) -> {
            ApiError err = (ApiError) exc;
            Map<String, Object> jsonMap = new HashMap<>();
            jsonMap.put("status", err.getStatusCode());
            jsonMap.put("errorMessage", err.getMessage());

        //every response will be application/json
        //therefore we can use a filter to add the type to all responses
        after((req, res) -> {

And my ApiTest.java file:

package com.teamtreehouse.courses.model;

import com.google.gson.Gson;
import com.teamtreehouse.courses.dao.CourseDao;
import com.teamtreehouse.courses.dao.Sql2oCourseDao;
import com.teamtreehouse.testing.ApiClient;
import com.teamtreehouse.testing.ApiResponse;
import org.junit.*;
import org.sql2o.Connection;
import org.sql2o.Sql2o;
import spark.Spark;

import java.util.HashMap;
import java.util.Map;

import static org.junit.Assert.*;

public class ApiTest {

    private static final String PORT = "4568";
    private static final String  TEST_DATASOURCE = "jdbc:h2:mem:testing";
    private Connection conn;
    private ApiClient client;
    private Sql2oCourseDao dao;
    private Gson gson;

    private Course newTestCourse() {
        return new Course("Test", "http://test.com");

    public static void startServer() {
        String[] args = {PORT, TEST_DATASOURCE};

    public static void stopServer() {

    public void setUp() throws Exception {
        Sql2o sql2o = new Sql2o(String.format("%s;INIT=RUNSCRIPT from 'classpath:db/init.sql'", TEST_DATASOURCE), "", "");
        dao = new Sql2oCourseDao(sql2o);
        conn = sql2o.open();
        client = new ApiClient("http://localhost:" + PORT);
        gson = new Gson();


    public void tearDown() throws Exception {

    public void addingCoursesReturnsCreatedStatus() throws Exception {
        Map<String, String> values = new HashMap<>();
        values.put("name", "test");
        values.put("url", "http://test.com");

        ApiResponse res = client.request("POST", "/courses", gson.toJson(values));

        assertEquals(201, res.getStatusCode());


    public void coursesCanBeAccessedById() throws Exception {
        Course course = newTestCourse();

        ApiResponse res = client.request("GET", "/courses/" + course.getId());

        Course retrieved = gson.fromJson(res.getBody(), Course.class);

        assertEquals(course, retrieved);

    public void missingCoursesReturnNotFoundStatus() throws Exception {
        ApiResponse res = client.request("GET", "/courses/42");

        assertEquals(404, res.getStatusCode());

And my ApiClient.java file:

package com.teamtreehouse.testing;

import spark.utils.IOUtils;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;

public class ApiClient {
    private String server;

    public ApiClient(String server) {
        this.server = server;

    public ApiResponse request(String method, String uri) {
        return request(method, uri, null);

    public ApiResponse request(String method, String uri, String requestBody) {
        try {
            URL url = new URL(server + uri);
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            connection.setRequestProperty("Content-Type", "application/json");
            if (requestBody != null) {
                try (OutputStream os = connection.getOutputStream()) {
            InputStream inputStream = connection.getResponseCode() < 400 ?
                    connection.getInputStream() :
            String body = IOUtils.toString(inputStream);
            return new ApiResponse(connection.getResponseCode(), body);
        } catch (IOException e) {
            throw new RuntimeException("Whoops!  Connection error");

1 Answer

Jeremiah Shore
Jeremiah Shore
31,168 Points

Can you share the output of the Run console from IntelliJ when you run those tests?