main_test.go

// main_test.go

package main

import (
	"bytes"
	"encoding/json"
	"fmt"
	"log"
	"net/http"
	"net/http/httptest"
	"os"
	"strconv"
	"testing"

	"github.com/xceejay/rest-api-starter/handlers"
)

//nolint
var svr handlers.Server

func TestMain(m *testing.M) {
	svr = handlers.Server{}

	svr.Initialize("root", "1234", "127.0.0.1:3306", "dogebook_test")

	ensureTableExists()

	code := m.Run()

	clearTable()

	os.Exit(code)
}

func ensureTableExists() {
	if err := svr.DB.Exec(tableCreationQuery); err != nil {
		log.Fatal(err)
	}
}

func clearTable() {
	svr.DB.Exec("DELETE FROM users")
	svr.DB.Exec("ALTER TABLE users AUTO_INCREMENT = 1")
}

const tableCreationQuery = `
CREATE TABLE IF NOT EXISTS users
(
    id INT AUTO_INCREMENT PRIMARY KEY,
    first_name VARCHAR(50) NOT NULL,
    dob VARCHAR(100) NOT NULL
)`

func TestEmptyTable(t *testing.T) {
	clearTable()

	req, _ := http.NewRequest("GET", "/users", nil)
	response := executeRequest(req)

	checkResponseCode(t, http.StatusOK, response.Code)

	if body := response.Body.String(); body != "[]" {
		t.Errorf("Expected an empty array. Got %s", body)
	}
}

func executeRequest(req *http.Request) *httptest.ResponseRecorder {
	rr := httptest.NewRecorder()
	svr.Router.ServeHTTP(rr, req)

	return rr
}

func checkResponseCode(t *testing.T, expected, actual int) {
	if expected != actual {
		t.Errorf("Expected response code %d. Got %d\n", expected, actual)
	}
}

func TestGetNonExistentUser(t *testing.T) {
	clearTable()

	req, _ := http.NewRequest("GET", "/user/45", nil)
	response := executeRequest(req)

	checkResponseCode(t, http.StatusNotFound, response.Code)

	var m map[string]string
	json.Unmarshal(response.Body.Bytes(), &m)
	if m["error"] != "User not found" {
		t.Errorf("Expected the 'error' key of the response to be set to 'User not found'. Got '%s'", m["error"])
	}
}

func TestCreateUser(t *testing.T) {
	clearTable()

	payload := []byte(`{"first_name":"test user","dob":"30"}`)

	req, _ := http.NewRequest("POST", "/user", bytes.NewBuffer(payload))
	response := executeRequest(req)

	checkResponseCode(t, http.StatusCreated, response.Code)

	var m map[string]interface{}
	json.Unmarshal(response.Body.Bytes(), &m)

	if m["first_name"] != "test user" {
		t.Errorf("Expected user first_name to be 'test user'. Got '%v'", m["first_name"])
	}

	if m["dob"] != "30" {
		t.Errorf("Expected user dob to be '30'. Got '%v'", m["dob"])
	}

	// the id is compared to 1.0 because JSON unmarshaling converts numbers to
	// floats, when the target is a map[string]interface{}
	if m["id"] != 1.0 {
		t.Errorf("Expected product ID to be '1'. Got '%v'", m["id"])
	}
}

func addUsers(count int) {
	if count < 1 {
		count = 1
	}

	for i := 0; i < count; i++ {
		statement := fmt.Sprintf("INSERT INTO users(first_name, dob) VALUES('%s', %s)", ("User " + strconv.Itoa(i+1)), strconv.Itoa((i+1)*10))
		svr.DB.Exec(statement)
	}
}

func TestGetUser(t *testing.T) {
	clearTable()
	addUsers(1)

	req, _ := http.NewRequest("GET", "/user/1", nil)
	response := executeRequest(req)

	checkResponseCode(t, http.StatusOK, response.Code)
}

func TestUpdateUser(t *testing.T) {
	clearTable()
	addUsers(1)

	req, _ := http.NewRequest("GET", "/user/1", nil)
	response := executeRequest(req)
	var originalUser map[string]interface{}
	json.Unmarshal(response.Body.Bytes(), &originalUser)

	payload := []byte(`{"first_name":"test user - updated first_name","dob":"21"}`)

	req, _ = http.NewRequest("PUT", "/user/1", bytes.NewBuffer(payload))
	response = executeRequest(req)

	checkResponseCode(t, http.StatusOK, response.Code)

	var m map[string]interface{}
	json.Unmarshal(response.Body.Bytes(), &m)

	if m["id"] != originalUser["id"] {
		t.Errorf("Expected the id to remain the same (%v). Got %v", originalUser["id"], m["id"])
	}

	if m["first_name"] == originalUser["first_name"] {
		t.Errorf("Expected the first_name to change from '%v' to '%v'. Got '%v'", originalUser["first_name"], m["first_name"], m["first_name"])
	}

	if m["dob"] == originalUser["dob"] {
		t.Errorf("Expected the dob to change from '%v' to '%v'. Got '%v'", originalUser["dob"], m["dob"], m["dob"])
	}
}

func TestDeleteUser(t *testing.T) {
	clearTable()
	addUsers(1)

	req, _ := http.NewRequest("GET", "/user/1", nil)
	response := executeRequest(req)
	checkResponseCode(t, http.StatusOK, response.Code)

	req, _ = http.NewRequest("DELETE", "/user/1", nil)
	response = executeRequest(req)

	checkResponseCode(t, http.StatusOK, response.Code)

	req, _ = http.NewRequest("GET", "/user/1", nil)
	response = executeRequest(req)
	checkResponseCode(t, http.StatusNotFound, response.Code)
}