diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index ff40e8a..dfb6b9b 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -1,24 +1,27 @@
 <?xml version="1.0" encoding="UTF-8"?>
 
-<!-- http://www.phpunit.de/manual/current/en/appendixes.configuration.html -->
-<phpunit
-    backupGlobals               = "false"
-    backupStaticAttributes      = "false"
-    colors                      = "true"
-    convertErrorsToExceptions   = "true"
-    convertNoticesToExceptions  = "true"
-    convertWarningsToExceptions = "true"
-    processIsolation            = "true"
-    stopOnFailure               = "false"
-    syntaxCheck                 = "false"
-    bootstrap                   = "bootstrap.php" >
+<phpunit bootstrap="tests/bootstrap.php"
+         backupGlobals="false"
+         backupStaticAttributes="false"
+         colors="true"
+         verbose="true"
+         convertErrorsToExceptions="true"
+         convertNoticesToExceptions="true"
+         convertWarningsToExceptions="true"
+         processIsolation="false"
+         stopOnFailure="false">
 
     <testsuites>
 
         <testsuite name="php">
-            <directory>./tests/*/Tests</directory>
+            <directory>./tests/AtolOnlineClient</directory>
         </testsuite>
 
     </testsuites>
 
+    <filter>
+        <whitelist>
+            <directory>src</directory>
+        </whitelist>
+    </filter>
 </phpunit>
diff --git a/tests/AtolOnlineClient/AtolOnlineApiTest.php b/tests/AtolOnlineClient/AtolOnlineApiTest.php
new file mode 100644
index 0000000..6bcf6f4
--- /dev/null
+++ b/tests/AtolOnlineClient/AtolOnlineApiTest.php
@@ -0,0 +1,420 @@
+<?php
+
+namespace AtolOnlineClient\AtolOnlineClient;
+
+use AtolOnlineClient\AtolOnline;
+use AtolOnlineClient\AtolOnlineApi;
+use AtolOnlineClient\Configuration\Connection;
+use AtolOnlineClient\Request\V4\PaymentReceiptRequest;
+use AtolOnlineClient\Request\V4\ReceiptRequest;
+use AtolOnlineClient\Request\V4\ServiceRequest;
+use Doctrine\Common\Cache\ArrayCache;
+use Guzzle\Http\Client;
+use Guzzle\Http\Message\Response;
+use Guzzle\Plugin\Mock\MockPlugin;
+use PHPUnit\Framework\TestCase;
+use Psr\Log\NullLogger;
+use Psr\Log\Test\TestLogger;
+
+/**
+ * Class AtolOnlineApiTest
+ *
+ * @package AtolOnlineClient\AtolOnlineClient
+ */
+class AtolOnlineApiTest extends TestCase
+{
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\AtolOnlineApi::__construct
+     * @covers \AtolOnlineClient\AtolOnlineApi::setLogger
+     * @covers \AtolOnlineClient\AtolOnlineApi::setCache
+     * @covers \AtolOnlineClient\AtolOnlineApi::setVersion
+     * @covers \AtolOnlineClient\AtolOnlineApi::getVersion
+     */
+    public function testCreateApi(): void
+    {
+        $api = new AtolOnlineApi(new Client(), new Connection());
+
+        $this->assertInstanceOf(AtolOnlineApi::class, $api);
+
+        $this->assertSame(AtolOnlineApi::API_VERSION_V3, $api->getVersion());
+
+        $api->setVersion(AtolOnlineApi::API_VERSION_V4);
+        $this->assertSame(AtolOnlineApi::API_VERSION_V4, $api->getVersion());
+
+        $api->setLogger(new NullLogger());
+        $this->assertInstanceOf(NullLogger::class, $this->getProperty($api, 'logger'));
+
+        $api->setCache(new ArrayCache());
+        $this->assertInstanceOf(ArrayCache::class, $this->getProperty($api, 'cache'));
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\AtolOnlineApi::sell
+     */
+    public function testSell(): void
+    {
+        $responses = [
+            new Response(200, [], $this->getTokenSuccessResponseV4()),
+            new Response(200, [], $this->getReportSuccessReportV4()),
+        ];
+
+        $request = (new AtolOnline())->serializeOperationRequest($this->getPaymentRecepientRequest());
+
+        $api = $this->getApi($responses);
+        $api->setCache(new ArrayCache());
+
+        $response = $api->sell($request);
+
+        $this->assertSame('2ea26f17–0884–4f08–b120–306fc096a58f', json_decode($response, true)['uuid']);
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\AtolOnlineApi::sellRefund
+     */
+    public function testSellRefund(): void
+    {
+        $responses = [
+            new Response(200, [], $this->getTokenSuccessResponseV4()),
+            new Response(200, [], $this->getReportSuccessReportV4()),
+        ];
+
+        $request = (new AtolOnline())->serializeOperationRequest($this->getPaymentRecepientRequest());
+
+        $api = $this->getApi($responses);
+        $api->setCache(new ArrayCache());
+
+        $response = $api->sellRefund($request);
+
+        $this->assertSame('2ea26f17–0884–4f08–b120–306fc096a58f', json_decode($response, true)['uuid']);
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\AtolOnlineApi::checkStatus
+     */
+    public function testCheckStatusSuccessResponse(): void
+    {
+        $responses = [
+            new Response(200, [], $this->getTokenSuccessResponseV4()),
+            new Response(200, [], $this->getReportSuccessReportV4()),
+        ];
+
+        $api = $this->getApi($responses);
+        $api->setCache(new ArrayCache());
+
+        $response = $this->callMethod($api, 'checkStatus', [
+            'uuid' => '2ea26f17–0884–4f08–b120–306fc096a58f',
+        ]);
+
+        $this->assertSame('2ea26f17–0884–4f08–b120–306fc096a58f', json_decode($response, true)['uuid']);
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\AtolOnlineApi::getToken
+     */
+    public function testGetTokenSuccessResponse(): void
+    {
+        $api = $this->getApi([new Response(200, [], $this->getTokenSuccessResponseV4())]);
+        $api->setCache(new ArrayCache());
+
+        $this->assertSame('fj45u923j59ju42395iu9423i59243u0', $this->callMethod($api, 'getToken'));
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\AtolOnlineApi::getToken
+     */
+    public function testGetTokenErrorResponseWithLogger(): void
+    {
+        $logger = new TestLogger();
+
+        $api = $this->getApi([new Response(200, [], $this->getErrorResponseV4())]);
+        $api->setLogger($logger);
+        $api->setCache(new ArrayCache());
+
+        $this->assertFalse($this->callMethod($api, 'getToken'));
+        $this->assertTrue($logger->hasError('12 Неверный логин или пароль'));
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\AtolOnlineApi::getToken
+     */
+    public function testGetTokenSuccessResponseWithCache(): void
+    {
+        $cache = new ArrayCache();
+
+        $api = $this->getApi([new Response(200, [], $this->getTokenSuccessResponseV4())]);
+        $api->setCache($cache);
+
+        $this->assertSame('fj45u923j59ju42395iu9423i59243u0', $this->callMethod($api, 'getToken'));
+        $this->assertTrue($cache->contains($this->callMethod($api, 'getTokenCacheKey')));
+
+        $this->assertSame('fj45u923j59ju42395iu9423i59243u0', $this->callMethod($api, 'getToken'));
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\AtolOnlineApi::getToken
+     */
+    public function testGetTokenSuccessResponseV3(): void
+    {
+        $api = $this->getApi([new Response(200, [], $this->getTokenSuccessResponseV3())]);
+        $api->setVersion(AtolOnlineApi::API_VERSION_V3);
+        $api->setCache(new ArrayCache());
+
+        $this->assertSame('fj45u923j59ju42395iu9423i59243u0', $this->callMethod($api, 'getToken'));
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\AtolOnlineApi::getToken
+     */
+    public function testGetTokenSuccessResponseV3WithCache(): void
+    {
+        $cache = new ArrayCache();
+
+        $api = $this->getApi([new Response(200, [], $this->getTokenSuccessResponseV3())]);
+        $api->setCache($cache);
+        $api->setVersion(AtolOnlineApi::API_VERSION_V3);
+
+        $this->assertSame('fj45u923j59ju42395iu9423i59243u0', $this->callMethod($api, 'getToken'));
+        $this->assertTrue($cache->contains($this->callMethod($api, 'getTokenCacheKey')));
+
+        $this->assertSame('fj45u923j59ju42395iu9423i59243u0', $this->callMethod($api, 'getToken'));
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\AtolOnlineApi::buildUrl
+     */
+    public function testBuildUrlWithoutToken(): void
+    {
+        $args = ['operation' => 'test'];
+
+        $this->assertSame('https://online.atol.ru/possystem/v4/group/test', $this->callMethod($this->getApi(), 'buildUrl', $args));
+
+        $api = $this->getApi();
+        $api->setVersion(AtolOnlineApi::API_VERSION_V3);
+        $this->assertSame('https://online.atol.ru/possystem/v3/group/test', $this->callMethod($api, 'buildUrl', $args));
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\AtolOnlineApi::buildUrl
+     */
+    public function testBuildUrlWithToken(): void
+    {
+        $args = ['operation' => 'test', 'token' => 'test'];
+
+        $this->assertSame('https://online.atol.ru/possystem/v4/group/test?token=test', $this->callMethod($this->getApi(), 'buildUrl', $args));
+
+        $api = $this->getApi();
+        $api->setVersion(AtolOnlineApi::API_VERSION_V3);
+        $this->assertSame('https://online.atol.ru/possystem/v3/group/test?tokenid=test', $this->callMethod($api, 'buildUrl', $args));
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\AtolOnlineApi::sendOperationRequest
+     */
+    public function testSendOperationRequestSuccessResponse(): void
+    {
+        $responses = [
+            new Response(200, [], $this->getTokenSuccessResponseV4()),
+            new Response(200, [], $this->getTokenSuccessResponseV4())
+        ];
+
+        $request = (new AtolOnline())->serializeOperationRequest($this->getPaymentRecepientRequest());
+
+        $api = $this->getApi($responses);
+        $api->setCache(new ArrayCache());
+
+        $response = $this->callMethod($api, 'sendOperationRequest', [
+            'operation' => 'sell',
+            'data' => $request,
+        ]);
+
+        $this->assertSame('fj45u923j59ju42395iu9423i59243u0', json_decode($response->getBody(), true)['token']);
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\AtolOnlineApi::logDebug
+     */
+    public function testLogDebug(): void
+    {
+        $logger = new TestLogger();
+
+        $api = $this->getApi();
+        $api->setLogger($logger);
+
+        $this->callMethod($api, 'logDebug', [
+            'url' => '/test',
+            'data' => 'test',
+            'response' => new Response(200, ['X-Foo' => 'Bar', 'X-Foo2' => 'Bar2'], 'test'),
+        ]);
+
+        $this->assertTrue($logger->hasDebug("* URL: /test\n * POSTFIELDS: test\n * RESPONSE HEADERS: HTTP/1.1 200 OK\r\nX-Foo: Bar\r\nX-Foo2: Bar2\r\n\r\n\n * RESPONSE BODY: test\n * ATTEMPTS: 0"));
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\AtolOnlineApi::getTokenCacheKey
+     */
+    public function testGetTokenCacheKey(): void
+    {
+        $this->assertSame('crm_fiscal_atol_online_token_68526766e6751745b52ae70b7bd3c6fe_v4', $this->callMethod($this->getApi(), 'getTokenCacheKey'));
+
+
+        $api = $this->getApi();
+        $api->setVersion(AtolOnlineApi::API_VERSION_V3);
+
+        $this->assertSame('crm_fiscal_atol_online_token_68526766e6751745b52ae70b7bd3c6fe_v3', $this->callMethod($api, 'getTokenCacheKey'));
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\AtolOnlineApi::isTokenExpired
+     */
+    public function testIsTokenExpired(): void
+    {
+        $body = new \stdClass();
+        $body->error = new \stdClass();
+        $body->error->code = 4;
+
+        $this->assertTrue($this->callMethod($this->getApi(), 'isTokenExpired', ['body' => $body]));
+
+        $body = new \stdClass();
+        $this->assertFalse($this->callMethod($this->getApi(), 'isTokenExpired', ['body' => $body]));
+    }
+
+    /**
+     * @param array $responses
+     * @param bool $debug
+     * @param bool $test
+     * @return AtolOnlineApi
+     */
+    private function getApi(array $responses = [], bool $debug = true, bool $test = false): AtolOnlineApi
+    {
+        $connection = new Connection();
+        $connection->login = 'login';
+        $connection->pass = 'pass';
+        $connection->group = 'group';
+        $connection->sno = Connection::SNO_GENERAL;
+        $connection->version = AtolOnlineApi::API_VERSION_V4;
+        $connection->setDebug($debug);
+        $connection->setTestMode($test);
+
+        $plugin = new MockPlugin();
+
+        foreach ($responses as $response) {
+            $plugin->addResponse($response);
+        }
+
+        $client = new Client();
+        $client->addSubscriber($plugin);
+
+        return new AtolOnlineApi($client, $connection);
+    }
+
+    /**
+     * @param mixed $object
+     * @param string $name
+     * @param array $args
+     * @return mixed
+     */
+    private function callMethod($object, string $name, array $args = [])
+    {
+        $reflection = new \ReflectionClass($object);
+        $method = $reflection->getMethod($name);
+        $method->setAccessible(true);
+
+        return $method->invokeArgs($object, $args);
+    }
+
+    /**
+     * @param mixed $object
+     * @param string $name
+     * @return mixed
+     */
+    private function getProperty($object, string $name)
+    {
+        $reflection = new \ReflectionClass($object);
+        $property = $reflection->getProperty($name);
+        $property->setAccessible(true);
+
+        return $property->getValue($object);
+    }
+
+    /**
+     * @return false|string
+     */
+    private function getTokenSuccessResponseV3()
+    {
+        return json_encode([
+            'token' => 'fj45u923j59ju42395iu9423i59243u0',
+            'code' => 1,
+        ]);
+    }
+
+    /**
+     * @return false|string
+     */
+    private function getTokenSuccessResponseV4()
+    {
+        return json_encode([
+            'error' => null,
+            'token' => 'fj45u923j59ju42395iu9423i59243u0',
+            'timestamp' => '30.11.2017 17:58:53',
+        ]);
+    }
+
+    /**
+     * @return false|string
+     */
+    private function getErrorResponseV4()
+    {
+        return json_encode([
+            'error' => [
+                'error_id' => '4475d6d8d-844d-4d05-aa8b-e3dbdf3defd5',
+                'code' => 12,
+                'text' => 'Неверный логин или пароль',
+                'type' => 'system',
+            ],
+            'timestamp' => '30.11.2017 17:58:53',
+        ]);
+    }
+
+    /**
+     * @return string
+     */
+    private function getReportSuccessReportV4(): string
+    {
+        return file_get_contents(__DIR__.'/../fixtures/success_response_v4_3.json');
+    }
+
+    /**
+     * @return PaymentReceiptRequest
+     */
+    private function getPaymentRecepientRequest(): PaymentReceiptRequest
+    {
+        $service = new ServiceRequest();
+        $service->setCallbackUrl('test.local');
+
+        $receipt = new ReceiptRequest();
+        $receipt->setTotal('100');
+
+        /** @var PaymentReceiptRequest $request */
+        $request = new PaymentReceiptRequest();
+        $request->setExternalId('test');
+        $request->setService($service);
+        $request->setReceipt($receipt);
+
+        return $request;
+    }
+}
diff --git a/tests/AtolOnlineClient/AtolOnlineTest.php b/tests/AtolOnlineClient/AtolOnlineTest.php
new file mode 100644
index 0000000..95cf87f
--- /dev/null
+++ b/tests/AtolOnlineClient/AtolOnlineTest.php
@@ -0,0 +1,244 @@
+<?php
+
+namespace AtolOnlineClient\Tests;
+
+use AtolOnlineClient\AtolOnline;
+use AtolOnlineClient\Configuration\Connection;
+use AtolOnlineClient\ConfigurationInterface;
+use AtolOnlineClient\Request\V4\PaymentReceiptRequest;
+use AtolOnlineClient\Request\V4\ReceiptRequest;
+use AtolOnlineClient\Request\V4\ServiceRequest;
+use Guzzle\Http\Client;
+use JMS\Serializer\Exception\RuntimeException;
+use JMS\Serializer\SerializerInterface;
+use PHPUnit\Framework\TestCase;
+
+class AtolOnlineTest extends TestCase
+{
+    /**
+     * @var AtolOnline
+     */
+    protected $atol;
+
+    /**
+     * @return void
+     */
+    public function setUp(): void
+    {
+        $this->atol =  new AtolOnline();
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\AtolOnline::__construct
+     */
+    public function testConstructor(): void
+    {
+        $reflection = new \ReflectionClass(get_class($this->atol));
+
+        $property = $reflection->getProperty('serializer');
+        $property->setAccessible(true);
+
+        $this->assertInstanceOf(SerializerInterface::class, $property->getValue($this->atol));
+    }
+
+    /**
+     * @covers \AtolOnlineClient\AtolOnline::createConfiguration
+     * @return void
+     */
+    public function testCreateConfiguration(): void
+    {
+        $this->assertInstanceOf(ConfigurationInterface::class, $this->atol->createConfiguration());
+    }
+
+    /**
+     * @param string $file
+     * @covers \AtolOnlineClient\AtolOnline::deserializeOperationResponse
+     * @dataProvider dataSuccessResponse
+     */
+    public function testSuccessDeserializeOperationResponse(string $file): void
+    {
+        $response = file_get_contents(__DIR__.'/../fixtures/'. $file);
+
+        $operationResponse = $this->atol->deserializeOperationResponse($response);
+
+        $this->assertEquals('12.04.2017 06:15:06', $operationResponse->getTimestamp());
+    }
+
+    /**
+     * @param string $file
+     * @covers \AtolOnlineClient\AtolOnline::deserializeOperationResponse
+     * @dataProvider dataErrorResponse
+     */
+    public function testErrorDeserializeOperationResponse(string $file): void
+    {
+        $response = file_get_contents(__DIR__.'/../fixtures/'. $file);
+
+        $operationResponse = $this->atol->deserializeOperationResponse($response);
+
+        $this->assertEquals('12.04.2017 06:15:06', $operationResponse->getTimestamp());
+        $this->assertEquals('fail', $operationResponse->getStatus());
+        $this->assertEquals(30, $operationResponse->getError()->getCode());
+        $this->assertEquals('system', $operationResponse->getError()->getType());
+
+        $this->assertEquals(
+            ' Передан некорректный UUID : "{0}". Необходимо повторить запрос с корректными данными ',
+            $operationResponse->getError()->getText()
+        );
+    }
+
+    /**
+     * @covers \AtolOnlineClient\AtolOnline::deserializeOperationResponse
+     */
+    public function testFailDeserializeOperationResponse(): void
+    {
+        $this->expectException(RuntimeException::class);
+
+        $this->atol->deserializeOperationResponse('<html></html>');
+    }
+
+    /**
+     * @param string $file
+     * @covers \AtolOnlineClient\AtolOnline::deserializeCheckStatusResponse
+     * @dataProvider dataSuccessResponse
+     */
+    public function testSuccessDeserializeCheckStatusResponse(string $file): void
+    {
+        $response = file_get_contents(__DIR__.'/../fixtures/'. $file);
+
+        $operationResponse = $this->atol->deserializeCheckStatusResponse($response);
+
+        $this->assertEquals('12.04.2017 06:15:06', $operationResponse->getTimestamp());
+    }
+
+    /**
+     * @covers \AtolOnlineClient\AtolOnline::deserializeCheckStatusResponse
+     */
+    public function testFailDeserializeCheckStatusResponse(): void
+    {
+        $this->expectException(RuntimeException::class);
+
+        $this->atol->deserializeCheckStatusResponse('<html></html>');
+    }
+
+    /**
+     * @covers \AtolOnlineClient\AtolOnline::serializeOperationRequest
+     */
+    public function testSerializeOperationRequest(): void
+    {
+        $service = new ServiceRequest();
+        $service->setCallbackUrl('test.local');
+
+        $receipt = new ReceiptRequest();
+        $receipt->setTotal('100');
+
+        /** @var PaymentReceiptRequest $paymentReceipt */
+        $paymentReceipt = new PaymentReceiptRequest();
+
+        $reflection = new \ReflectionClass($paymentReceipt);
+        $property = $reflection->getProperty('timestamp');
+        $property->setAccessible(true);
+        $property->setValue($paymentReceipt, 1);
+
+        $paymentReceipt->setExternalId('test');
+        $paymentReceipt->setService($service);
+        $paymentReceipt->setReceipt($receipt);
+
+        $request = $this->atol->serializeOperationRequest($paymentReceipt);
+
+        $this->assertEquals('{"external_id":"test","receipt":{"total":100},"timestamp":"1","service":{"callback_url":"test.local"}}', $request);
+    }
+
+    /**
+     * @return void
+     *
+     * @covers \AtolOnlineClient\AtolOnline::createApi
+     */
+    public function testCreateApi(): void
+    {
+        $api1 =  $this->atol->createApi(new Client(), new Connection());
+        $api2 =  $this->atol->createApi(new Client(), new Connection());
+
+        $this->assertSame($api1, $api2);
+    }
+
+    /**
+     * @return void
+     *
+     * @covers \AtolOnlineClient\AtolOnline::getApi
+     */
+    public function testGetApi(): void
+    {
+        $api1 =  $this->atol->createApi(new Client(), new Connection());
+        $api2 =  $this->atol->getApi();
+
+        $this->assertSame($api1, $api2);
+    }
+
+    /**
+     * @return array
+     */
+    public function dataSuccessResponse(): array
+    {
+        return [
+            ['success_response_v4_1.json'],
+            ['success_response_v4_2.json'],
+            ['success_response_v4_3.json'],
+        ];
+    }
+
+    /**
+     * @return array
+     */
+    public function dataErrorResponse(): array
+    {
+        return [
+            ['error_response_v3.json'],
+            ['error_response_v4.json']
+        ];
+    }
+
+    /**
+     * @return array
+     */
+    public function dataInvalidResponse(): array
+    {
+        return [
+            [
+                'code' => 404,
+                'message' => 'Not Found',
+                'html' => '<html><head><title>404 Not Found</title></head><body><center><h1>404 Not Found</h1></center><hr><center>openresty/1.15.8.1rc1</center></body></html>',
+            ],
+            [
+                'code' => 502,
+                'message' => 'Bad Gateway',
+                'html' => '<html><head><title>502 Bad Gateway</title></head><body><center><h1>502 Bad Gateway</h1></center><hr><center>nginx/1.15.8</center></body></html>',
+            ],
+            [
+                'code' => null,
+                'message' => null,
+                'html' => '<html></html>',
+            ],
+            [
+                'code' => null,
+                'message' => null,
+                'html' => '',
+            ],
+        ];
+    }
+
+    /**
+     * @param mixed $object
+     * @param string $name
+     * @param array $args
+     * @return mixed
+     */
+    private function callMethod($object, string $name, array $args = [])
+    {
+        $reflection = new \ReflectionClass($object);
+        $method = $reflection->getMethod($name);
+        $method->setAccessible(true);
+
+        return $method->invokeArgs($object, $args);
+    }
+}
diff --git a/tests/AtolOnlineClient/Configuration/ConnectionTest.php b/tests/AtolOnlineClient/Configuration/ConnectionTest.php
new file mode 100644
index 0000000..37a9ff2
--- /dev/null
+++ b/tests/AtolOnlineClient/Configuration/ConnectionTest.php
@@ -0,0 +1,90 @@
+<?php
+
+namespace AtolOnlineClient\AtolOnlineClient\Connection;
+
+use AtolOnlineClient\AtolOnlineApi;
+use AtolOnlineClient\Configuration\Connection;
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Validator\Validation;
+
+class ConnectionTest extends TestCase
+{
+    /**
+     * @var Connection
+     */
+    private $connection;
+
+    /**
+     * @return void
+     */
+    public function setUp(): void
+    {
+        $this->connection = new Connection();
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\Configuration\Connection::setDebug
+     * @covers \AtolOnlineClient\Configuration\Connection::isDebug
+     */
+    public function testDebug(): void
+    {
+        $this->assertFalse($this->connection->isDebug());
+
+        $this->connection->setDebug(true);
+        $this->assertTrue($this->connection->isDebug());
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\Configuration\Connection::isTestMode
+     * @covers \AtolOnlineClient\Configuration\Connection::setTestMode
+     */
+    public function testTestMode(): void
+    {
+        $this->assertFalse($this->connection->isTestMode());
+
+        $this->connection->setTestMode(true);
+        $this->assertTrue($this->connection->isTestMode());
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\Configuration\Connection::getVersion
+     * @covers \AtolOnlineClient\Configuration\Connection::isVersion4
+     * @covers \AtolOnlineClient\Configuration\Connection::isVersion3
+     */
+    public function testVersion(): void
+    {
+        $this->connection->version = AtolOnlineApi::API_VERSION_V3;
+        $this->assertEquals(AtolOnlineApi::API_VERSION_V3, $this->connection->getVersion());
+        $this->assertTrue($this->connection->isVersion3());
+
+        $this->connection->version = AtolOnlineApi::API_VERSION_V4;
+        $this->assertTrue($this->connection->isVersion4());
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\Configuration\Connection::loadValidatorMetadata
+     */
+    public function testValidator(): void
+    {
+
+        $validator = Validation::createValidatorBuilder()
+            ->addMethodMapping('loadValidatorMetadata')
+            ->getValidator();
+
+        $list = $validator->validate($this->connection);
+
+        $this->assertEquals(3, $list->count());
+
+        $this->connection->login = 'login';
+        $this->connection->pass = 'login';
+        $this->connection->group = 'group';
+
+        $list = $validator->validate($this->connection);
+
+        $this->assertEquals(0, $list->count());
+    }
+}
diff --git a/tests/AtolOnlineClient/ConfigurationTest.php b/tests/AtolOnlineClient/ConfigurationTest.php
new file mode 100644
index 0000000..5afc5d8
--- /dev/null
+++ b/tests/AtolOnlineClient/ConfigurationTest.php
@@ -0,0 +1,79 @@
+<?php
+
+namespace AtolOnlineClient\AtolOnlineClient;
+
+use AtolOnlineClient\Configuration;
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Validator\Validation;
+
+/**
+ * Class ConfigurationTest
+ *
+ * @package AtolOnlineClient\AtolOnlineClient
+ */
+class ConfigurationTest extends TestCase
+{
+    /**
+     * @var Configuration
+     */
+    private $configuration;
+
+    public function setUp(): void
+    {
+        $this->configuration = new Configuration();
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\Configuration::isDebug
+     * @covers \AtolOnlineClient\Configuration::setDebug
+     */
+    public function testDebug(): void
+    {
+        $this->assertFalse((bool) $this->configuration->isDebug());
+
+        $this->configuration->setDebug(true);
+        $this->assertTrue($this->configuration->isDebug());
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\Configuration::isEnabled
+     * @covers \AtolOnlineClient\Configuration::setEnabled
+     */
+    public function testEnabled(): void
+    {
+        $this->configuration->setEnabled(true);
+        $this->assertTrue($this->configuration->isEnabled());
+
+        $this->configuration->setEnabled(false);
+        $this->assertFalse($this->configuration->isEnabled());
+    }
+
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\Configuration::loadValidatorMetadata
+     */
+    public function testValidator(): void
+    {
+
+        $validator = Validation::createValidatorBuilder()
+            ->addMethodMapping('loadValidatorMetadata')
+            ->getValidator();
+
+        $list = $validator->validate($this->configuration);
+
+        $this->assertEquals(1, $list->count());
+
+        $connection = new Configuration\Connection();
+        $connection->login = 'login';
+        $connection->pass = 'login';
+        $connection->group = 'group';
+
+        $this->configuration->connections[] = $connection;
+
+        $list = $validator->validate($this->configuration);
+
+        $this->assertEquals(0, $list->count());
+    }
+}
diff --git a/tests/AtolOnlineClient/Response/ResponseTest.php b/tests/AtolOnlineClient/Response/ResponseTest.php
new file mode 100644
index 0000000..6b71c30
--- /dev/null
+++ b/tests/AtolOnlineClient/Response/ResponseTest.php
@@ -0,0 +1,63 @@
+<?php
+
+namespace AtolOnlineClient\AtolOnlineClient\Response;
+
+use AtolOnlineClient\Response\OperationResponse;
+use JMS\Serializer\SerializerBuilder;
+use PHPUnit\Framework\TestCase;
+
+/**
+ */
+class ResponseTest extends TestCase
+{
+    /**
+     * @return void
+     * @covers \AtolOnlineClient\Response\OperationResponse
+     * @covers \AtolOnlineClient\Response\Error
+     * @covers \AtolOnlineClient\Response\Payload
+     */
+    public function testResponse(): void
+    {
+        $serializer = SerializerBuilder::create()->build();
+
+        $response = '{
+  "uuid": "4355",
+  "timestamp": "12.04.2017 06:15:06",
+  "status": "fail",
+  "error": {
+    "error_id": "475d6d8d-844d-4d05-aa8b-e3dbdf4defd6",
+    "code": 30,
+    "text": " Передан некорректный UUID : \"{0}\". Необходимо повторить запрос с корректными данными ",
+    "type": "system"
+  },
+  "payload": {
+    "total": 1598,
+    "fns_site": "www.nalog.ru",
+    "fn_number": "1110000100238211",
+    "shift_number": 23,
+    "receipt_datetime": "12.04.2017 20:16:00",
+    "fiscal_receipt_number": 6,
+    "fiscal_document_number": 133,
+    "ecr_registration_number": "0000111118041361",
+    "fiscal_document_attribute": 3449555941
+  },
+  "group_code": " MyCompany_MyShop",
+  "daemon_code": "prod–agent–1",
+  "device_code": "KSR13.00–1–11",
+  "external_id": "TRF10601_1",
+  "callback_url": ""
+}';
+        $response = $serializer->deserialize(
+            $response,
+            OperationResponse::class,
+            'json'
+        );
+
+        $serializer->serialize(
+            $response,
+            'json'
+        );
+
+        $this->assertTrue(true);
+    }
+}
diff --git a/tests/AtolOnlineClient/Tests/AtolOnlineTest.php b/tests/AtolOnlineClient/Tests/AtolOnlineTest.php
deleted file mode 100644
index ad5249d..0000000
--- a/tests/AtolOnlineClient/Tests/AtolOnlineTest.php
+++ /dev/null
@@ -1,46 +0,0 @@
-<?php
-
-namespace AtolOnlineClient\Tests;
-
-use AtolOnlineClient\AtolOnline;
-use AtolOnlineClient\Configuration;
-use AtolOnlineClient\Response\OperationResponse;
-use PHPUnit\Framework\TestCase;
-
-class AtolOnlineTest extends TestCase
-{
-
-    public function testCreateConfiguration()
-    {
-        $atol = new AtolOnline();
-        $this->assertInstanceOf(Configuration::class, $atol->createConfiguration());
-    }
-
-
-    /**
-     * @dataProvider dataSellErrorResponse
-     */
-    public function testDeserializeOperationResponse($file)
-    {
-        $response = file_get_contents(__DIR__ . '/data/'. $file);
-        $atol = new AtolOnline();
-        $operationResponse = $atol->deserializeOperationResponse($response);
-        $this->assertInstanceOf(OperationResponse::class, $operationResponse);
-        $this->assertEquals('12.04.2017 06:15:06', $operationResponse->getTimestamp());
-        $this->assertEquals('fail', $operationResponse->getStatus());
-        $this->assertEquals(30, $operationResponse->getError()->getCode());
-        $this->assertEquals('system', $operationResponse->getError()->getType());
-        $this->assertEquals(
-            ' Передан некорректный UUID : "{0}". Необходимо повторить запрос с корректными данными ',
-            $operationResponse->getError()->getText()
-        );
-    }
-
-    public function dataSellErrorResponse()
-    {
-        return [
-            ['sell_error_response_v3.json'],
-            ['sell_error_response_v3.json']
-        ];
-    }
-}
diff --git a/bootstrap.php b/tests/bootstrap.php
similarity index 79%
rename from bootstrap.php
rename to tests/bootstrap.php
index 8c24c52..6559848 100644
--- a/bootstrap.php
+++ b/tests/bootstrap.php
@@ -1,13 +1,13 @@
 <?php
+
 use Composer\Autoload\ClassLoader;
 use Doctrine\Common\Annotations\AnnotationRegistry;
 
 /**
  * @var ClassLoader $loader
  */
-$loader = require __DIR__.'/vendor/autoload.php';
+$loader = require __DIR__.'/../vendor/autoload.php';
 
 AnnotationRegistry::registerLoader('class_exists');
 
-
 return $loader;
diff --git a/tests/AtolOnlineClient/Tests/data/sell_error_response_v3.json b/tests/fixtures/error_response_v3.json
similarity index 100%
rename from tests/AtolOnlineClient/Tests/data/sell_error_response_v3.json
rename to tests/fixtures/error_response_v3.json
diff --git a/tests/AtolOnlineClient/Tests/data/sell_error_response_v4.json b/tests/fixtures/error_response_v4.json
similarity index 100%
rename from tests/AtolOnlineClient/Tests/data/sell_error_response_v4.json
rename to tests/fixtures/error_response_v4.json
diff --git a/tests/fixtures/success_response_v4_1.json b/tests/fixtures/success_response_v4_1.json
new file mode 100644
index 0000000..a7517bc
--- /dev/null
+++ b/tests/fixtures/success_response_v4_1.json
@@ -0,0 +1,5 @@
+{
+  "error": null,
+  "token": "fj45u923j59ju42395iu9423i59243u0",
+  "timestamp": "12.04.2017 06:15:06"
+}
diff --git a/tests/fixtures/success_response_v4_2.json b/tests/fixtures/success_response_v4_2.json
new file mode 100644
index 0000000..04837ab
--- /dev/null
+++ b/tests/fixtures/success_response_v4_2.json
@@ -0,0 +1,6 @@
+{
+  "uuid": "2ea26f17–0884–4f08–b120–306fc096a58f",
+  "timestamp": "12.04.2017 06:15:06",
+  "error": null,
+  "status": "wait"
+}
diff --git a/tests/fixtures/success_response_v4_3.json b/tests/fixtures/success_response_v4_3.json
new file mode 100644
index 0000000..f872274
--- /dev/null
+++ b/tests/fixtures/success_response_v4_3.json
@@ -0,0 +1,22 @@
+{
+  "uuid": "2ea26f17–0884–4f08–b120–306fc096a58f",
+  "error": null,
+  "status": "done",
+  "payload": {
+    "total": 1598,
+    "fns_site": "www.nalog.ru",
+    "fn_number": "1110000100238211",
+    "shift_number": 23,
+    "receipt_datetime": "12.04.2017 20:16:00",
+    "fiscal_receipt_number": 6,
+    "fiscal_document_number": 133,
+    "ecr_registration_number": "0000111118041361",
+    "fiscal_document_attribute": 3449555941
+  },
+  "timestamp": "12.04.2017 06:15:06",
+  "group_code": "MyCompany_MyShop",
+  "daemon_code": "prod–agent–1",
+  "device_code": "KSR13.00–1–11",
+  "external_id": "TRF10601_1",
+  "callback_url": ""
+}