From 6c807e2a88b784d5a42ea6b4157e3611d024dfe3 Mon Sep 17 00:00:00 2001
From: Kevin <34477826+kkevindev@users.noreply.github.com>
Date: Fri, 30 Jan 2026 20:49:06 +0100
Subject: [PATCH 1/2] Implemented Symfony HTTP Client.

---
 .php-cs-fixer.dist.php                        | 19 ++++
 composer.json                                 | 11 ++-
 phpstan.neon                                  |  1 +
 src/Client.php                                | 91 +++++++++----------
 src/Exceptions/HttpException.php              |  2 +-
 src/Http/Request/Headers.php                  | 39 --------
 src/Http/Response/Headers.php                 | 21 -----
 src/Http/Response/Response.php                | 62 -------------
 src/Postcode.php                              |  3 +-
 tests/AbstractClientTestCase.php              | 55 +++++++++++
 tests/ClientTest.php                          | 35 -------
 tests/Http/Request/HeadersTest.php            | 22 -----
 tests/Http/Response/HeadersTest.php           | 31 -------
 tests/Http/Response/ResponseTest.php          | 70 --------------
 tests/Integration/ClientTest.php              | 22 +++++
 tests/{ => Integration}/PostcodeTest.php      | 10 +-
 tests/Mock/MockResponseHttpClient.php         | 50 ++++++++++
 ...api_v1_postcode_postcode=0000AA&number=401 |  3 +
 ...1_postcode_postcode=0000AA&number=401.meta |  1 +
 ...api_v1_postcode_postcode=0000AA&number=404 |  1 +
 ...1_postcode_postcode=0000AA&number=404.meta |  1 +
 ..._v1_postcode_postcode=1012%20RJ&number=147 |  1 +
 .../api_v1_postcode_postcode=X&number=422     |  1 +
 ...api_v1_postcode_postcode=X&number=422.meta |  1 +
 tests/Unit/ClientTest.php                     | 17 ++++
 25 files changed, 238 insertions(+), 332 deletions(-)
 create mode 100644 .php-cs-fixer.dist.php
 delete mode 100644 src/Http/Request/Headers.php
 delete mode 100644 src/Http/Response/Headers.php
 delete mode 100644 src/Http/Response/Response.php
 create mode 100644 tests/AbstractClientTestCase.php
 delete mode 100644 tests/ClientTest.php
 delete mode 100644 tests/Http/Request/HeadersTest.php
 delete mode 100644 tests/Http/Response/HeadersTest.php
 delete mode 100644 tests/Http/Response/ResponseTest.php
 create mode 100644 tests/Integration/ClientTest.php
 rename tests/{ => Integration}/PostcodeTest.php (83%)
 create mode 100644 tests/Mock/MockResponseHttpClient.php
 create mode 100644 tests/Mock/Responses/api_v1_postcode_postcode=0000AA&number=401
 create mode 100644 tests/Mock/Responses/api_v1_postcode_postcode=0000AA&number=401.meta
 create mode 100644 tests/Mock/Responses/api_v1_postcode_postcode=0000AA&number=404
 create mode 100644 tests/Mock/Responses/api_v1_postcode_postcode=0000AA&number=404.meta
 create mode 100644 tests/Mock/Responses/api_v1_postcode_postcode=1012%20RJ&number=147
 create mode 100644 tests/Mock/Responses/api_v1_postcode_postcode=X&number=422
 create mode 100644 tests/Mock/Responses/api_v1_postcode_postcode=X&number=422.meta
 create mode 100644 tests/Unit/ClientTest.php

diff --git a/.php-cs-fixer.dist.php b/.php-cs-fixer.dist.php
new file mode 100644
index 0000000..4373b9d
--- /dev/null
+++ b/.php-cs-fixer.dist.php
@@ -0,0 +1,19 @@
+<?php
+
+declare(strict_types=1);
+
+use PhpCsFixer\Config;
+use PhpCsFixer\Finder;
+use PhpCsFixer\Runner\Parallel\ParallelConfigFactory;
+
+return (new Config())
+    ->setParallelConfig(ParallelConfigFactory::detect())
+    ->setRiskyAllowed(true)
+    ->setRules([
+        '@Symfony' => true
+    ])
+    ->setFinder(
+        (new Finder())
+            ->in(__DIR__)
+    )
+;
diff --git a/composer.json b/composer.json
index 7fc441e..e64fc72 100644
--- a/composer.json
+++ b/composer.json
@@ -4,23 +4,28 @@
     "license": "gpl-3.0-or-later",
     "type": "library",
     "require": {
-        "php": "^8.1"
+        "php": "^8.1",
+        "kkevindev/assert-return-value":"1.11.0",
+        "symfony/http-client": "^6.4 || ^7.0 || ^8.0"
     },
     "require-dev": {
         "phpunit/phpunit": "^9.6",
         "phpstan/phpstan": "^2.1",
         "friendsofphp/php-cs-fixer": "^v3.89"
     },
-
     "autoload": {
         "psr-4": {
             "Kkevindev\\PostcodeTech\\": "src/"
         }
     },
-
     "autoload-dev": {
         "psr-4": {
             "Kkevindev\\PostcodeTech\\Tests\\": "tests/"
         }
+    },
+    "scripts": {
+        "test": "vendor/bin/phpunit",
+        "cs-fix": "vendor/bin/php-cs-fixer fix",
+        "phpstan": "vendor/bin/phpstan analyse"
     }
 }
diff --git a/phpstan.neon b/phpstan.neon
index cfb8442..67fb864 100644
--- a/phpstan.neon
+++ b/phpstan.neon
@@ -3,3 +3,4 @@ parameters:
     level: 10
     paths:
         - src
+        - tests
diff --git a/src/Client.php b/src/Client.php
index da7fbcb..366a203 100644
--- a/src/Client.php
+++ b/src/Client.php
@@ -5,75 +5,74 @@
 use Kkevindev\PostcodeTech\Exceptions\HttpException;
 use Kkevindev\PostcodeTech\Exceptions\PostcodeNotFoundException;
 use Kkevindev\PostcodeTech\Exceptions\ValidationException;
-use Kkevindev\PostcodeTech\Http\Request\Headers;
-use Kkevindev\PostcodeTech\Http\Response\Response;
+use Symfony\Contracts\HttpClient\Exception\ClientExceptionInterface;
+use Symfony\Contracts\HttpClient\Exception\RedirectionExceptionInterface;
+use Symfony\Contracts\HttpClient\Exception\ServerExceptionInterface;
+use Symfony\Contracts\HttpClient\Exception\TransportExceptionInterface;
+use Symfony\Contracts\HttpClient\HttpClientInterface;
 
+/**
+ * @internal
+ */
 final class Client
 {
-    /** @var string */
-    private const BASE_URI = 'https://postcode.tech';
-
-    private Headers $headers;
-
     public function __construct(
         private readonly string $token,
+        private readonly HttpClientInterface $httpClient,
     ) {
-        $this->headers = new Headers([
-            'Authorization' => sprintf('Bearer %s', $this->token),
-        ]);
     }
 
     /**
-     * @throws PostcodeNotFoundException
-     * @throws ValidationException
-     * @throws HttpException
-     *
      * @return array{
      *     street: string,
      *     city: string,
      * }
+     *
+     * @throws PostcodeNotFoundException
+     * @throws ValidationException
+     * @throws HttpException
      */
     public function get(string $postcode, int $number): array
     {
-        $queryParameters = [
-            'postcode' => $postcode,
-            'number' => $number,
-        ];
+        try {
+            $response = $this->httpClient->request(
+                'GET',
+                'https://postcode.tech/api/v1/postcode',
+                [
+                    'auth_bearer' => $this->token,
+                    'query' => [
+                        'postcode' => $postcode,
+                        'number' => $number,
+                    ],
+                ],
+            );
 
-        $uri = sprintf(
-            '%s/%s?%s',
-            self::BASE_URI,
-            'api/v1/postcode',
-            http_build_query($queryParameters),
-        );
+            $statusCode = $response->getStatusCode();
 
-        $response = file_get_contents(
-            $uri,
-            false,
-            stream_context_create([
-                'http' => [
-                    'method' => 'GET',
-                    'header' => $this->headers->getHeaders(),
-                    'ignore_errors' => true,
-                ],
-            ]),
-        );
+            $responseBody = $response->getContent(false);
+        } catch (TransportExceptionInterface|ClientExceptionInterface|RedirectionExceptionInterface|ServerExceptionInterface $exception) {
+            throw new HttpException($exception->getMessage(), previous: $exception);
+        }
 
-        if (!$response) {
-            throw new HttpException('No response received from the API.');
+        if (200 > $statusCode || 300 <= $statusCode) {
+            throw match ($statusCode) {
+                401 => new HttpException('Unauthorized', $responseBody),
+                404 => new PostcodeNotFoundException('No results found for the given postcode and number.', $responseBody),
+                422 => new ValidationException('The request data was invalid.', $responseBody),
+                default => new HttpException('An unknown error occurred while fetching the data from the API.', $responseBody),
+            };
         }
 
-        // @todo refactor the magic '$http_response_header' to 'http_get_last_response_headers()' when PHP 8.4 is the lowest supported version.
-        $response = new Response($response, $http_response_header);
+        try {
+            $array = json_decode($responseBody, true, 512, JSON_THROW_ON_ERROR);
+        } catch (\JsonException $exception) {
+            throw new HttpException('The response body is not a valid JSON array.', $responseBody, $exception);
+        }
 
-        if (!$response->isSuccess()) {
-            match ($response->getHeaders()->getStatusCode()) {
-                404 => throw new PostcodeNotFoundException('No results found for the given postcode and number.', $response->getResponseBody()),
-                422 => throw new ValidationException('The request data was invalid.', $response->getResponseBody()),
-                default => throw new HttpException('An unknown error occurred while fetching the data from the API.', $response->getResponseBody()),
-            };
+        if (!is_array($array) || empty($array['street']) || !is_string($array['street']) || empty($array['city']) || !is_string($array['city'])) {
+            throw new HttpException('The response body did not contain the expected data.', $responseBody);
         }
 
-        return $response->getResponseBodyAsArray();
+        return $array;
     }
 }
diff --git a/src/Exceptions/HttpException.php b/src/Exceptions/HttpException.php
index 8ce4bca..a1e673e 100644
--- a/src/Exceptions/HttpException.php
+++ b/src/Exceptions/HttpException.php
@@ -4,7 +4,7 @@
 
 class HttpException extends \Exception
 {
-    public function __construct(string $message = "", string $responseBody = "", ?\Throwable $previous = null)
+    public function __construct(string $message = '', string $responseBody = '', ?\Throwable $previous = null)
     {
         parent::__construct(sprintf('%s: %s', $message, $responseBody), previous: $previous);
     }
diff --git a/src/Http/Request/Headers.php b/src/Http/Request/Headers.php
deleted file mode 100644
index 2949b06..0000000
--- a/src/Http/Request/Headers.php
+++ /dev/null
@@ -1,39 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Kkevindev\PostcodeTech\Http\Request;
-
-final class Headers
-{
-    /**
-     * @var array<string, string>
-     */
-    private array $headers = [];
-
-    /**
-     * @param array<string, string> $headers
-     */
-    public function __construct(array $headers = [])
-    {
-        foreach ($headers as $key => $value) {
-            $this->addHeader($key, $value);
-        }
-    }
-
-    public function addHeader(string $key, string $value): void
-    {
-        $this->headers[$key] = $value;
-    }
-
-    public function getHeaders(): string
-    {
-        $headers = '';
-
-        foreach ($this->headers as $key => $value) {
-            $headers .=  "{$key}: {$value}\r\n";
-        }
-
-        return $headers;
-    }
-}
diff --git a/src/Http/Response/Headers.php b/src/Http/Response/Headers.php
deleted file mode 100644
index ecd983f..0000000
--- a/src/Http/Response/Headers.php
+++ /dev/null
@@ -1,21 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Kkevindev\PostcodeTech\Http\Response;
-
-final class Headers
-{
-    /**
-     * @param string[] $headers
-     */
-    public function __construct(
-        private readonly array $headers,
-    ) {
-    }
-
-    public function getStatusCode(): int
-    {
-        return intval(explode(' ', $this->headers[0])[1]);
-    }
-}
diff --git a/src/Http/Response/Response.php b/src/Http/Response/Response.php
deleted file mode 100644
index 3f4a2e7..0000000
--- a/src/Http/Response/Response.php
+++ /dev/null
@@ -1,62 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Kkevindev\PostcodeTech\Http\Response;
-
-use Kkevindev\PostcodeTech\Exceptions\HttpException;
-
-final class Response
-{
-    private readonly Headers $headers;
-
-    /**
-     * @param string[] $responseHeaders
-     */
-    public function __construct(
-        private readonly string $responseBody,
-        array $responseHeaders,
-    ) {
-        $this->headers = new Headers($responseHeaders);
-    }
-
-    public function getResponseBody(): string
-    {
-        return $this->responseBody;
-    }
-
-    /**
-     * @throws HttpException
-     *
-     * @return array{
-     *     street: string,
-     *     city: string,
-     * }
-     */
-    public function getResponseBodyAsArray(): array
-    {
-        try {
-            $array = json_decode($this->responseBody, true, flags: JSON_THROW_ON_ERROR);
-        } catch (\JsonException $exception) {
-            throw new HttpException('The response body is not a valid JSON array.', $this->responseBody, $exception);
-        }
-
-        if (!is_array($array) || empty($array['street']) || !is_string($array['street']) || empty($array['city']) || !is_string($array['city'])) {
-            throw new HttpException('The response body did not contain the expected data.', $this->responseBody);
-        }
-
-        return $array;
-    }
-
-    public function getHeaders(): Headers
-    {
-        return $this->headers;
-    }
-
-    public function isSuccess(): bool
-    {
-        $statusCode = $this->headers->getStatusCode();
-
-        return $statusCode >= 200 && $statusCode < 300;
-    }
-}
diff --git a/src/Postcode.php b/src/Postcode.php
index 5ac3171..b986c62 100644
--- a/src/Postcode.php
+++ b/src/Postcode.php
@@ -5,6 +5,7 @@
 use Kkevindev\PostcodeTech\Exceptions\HttpException;
 use Kkevindev\PostcodeTech\Exceptions\PostcodeNotFoundException;
 use Kkevindev\PostcodeTech\Exceptions\ValidationException;
+use Symfony\Component\HttpClient\HttpClient;
 
 class Postcode implements PostcodeInterface
 {
@@ -23,7 +24,7 @@ protected function __construct(
      */
     public static function search(string $postcode, int $number, string $token): self
     {
-        $client = new Client($token);
+        $client = new Client($token, HttpClient::create());
 
         $response = $client->get($postcode, $number);
 
diff --git a/tests/AbstractClientTestCase.php b/tests/AbstractClientTestCase.php
new file mode 100644
index 0000000..9c925c5
--- /dev/null
+++ b/tests/AbstractClientTestCase.php
@@ -0,0 +1,55 @@
+<?php
+
+namespace Kkevindev\PostcodeTech\Tests;
+
+use Kkevindev\PostcodeTech\Client;
+use Kkevindev\PostcodeTech\Exceptions\HttpException;
+use Kkevindev\PostcodeTech\Exceptions\PostcodeNotFoundException;
+use Kkevindev\PostcodeTech\Exceptions\ValidationException;
+use PHPUnit\Framework\TestCase;
+
+abstract class AbstractClientTestCase extends TestCase
+{
+    abstract protected function getClient(string $token): Client;
+
+    public function testValid200ResponseReturnsResult(): void
+    {
+        $expectedStreet = 'Nieuwezijds Voorburgwal';
+        $expectedCity = 'Amsterdam';
+
+        $result = $this->getClient('demo')->get('1012 RJ', 147);
+
+        self::assertEquals($expectedStreet, $result['street']);
+        self::assertEquals($expectedCity, $result['city']);
+    }
+
+    public function test401ResponseThrowsException(): void
+    {
+        $this->expectException(HttpException::class);
+        $this->expectExceptionMessage(
+            <<<HTML
+            Unauthorized: {
+                "message": "Unauthorized"
+            }
+            HTML
+        );
+
+        $this->getClient('invalid-token')->get('0000AA', 401);
+    }
+
+    public function test404ResponseThrowsException(): void
+    {
+        $this->expectException(PostcodeNotFoundException::class);
+        $this->expectExceptionMessage('No results found for the given postcode and number.: {"message":"No result for this combination."}');
+
+        $this->getClient('demo')->get('0000AA', 404);
+    }
+
+    public function test422ResponseThrowsExceptionWhenMalformedInput(): void
+    {
+        $this->expectException(ValidationException::class);
+        $this->expectExceptionMessage('The request data was invalid.: {"message":"The given data was invalid.","errors":{"postcode":["Postcode should be formatted `1111AA` or `1111 AA`."]}}');
+
+        $this->getClient('demo')->get('X', 422);
+    }
+}
diff --git a/tests/ClientTest.php b/tests/ClientTest.php
deleted file mode 100644
index 4975bc8..0000000
--- a/tests/ClientTest.php
+++ /dev/null
@@ -1,35 +0,0 @@
-<?php
-
-
-use Kkevindev\PostcodeTech\Client;
-use PHPUnit\Framework\TestCase;
-
-final class ClientTest extends TestCase
-{
-    private Client $client;
-
-    protected function setUp(): void
-    {
-        $this->client = new Client('demo');
-    }
-
-    public static function providePostcodeData(): iterable
-    {
-        yield ['1012 RJ', 147, 'Nieuwezijds Voorburgwal', 'Amsterdam'];
-        yield ['2514 GL', 68, 'Noordeinde', "'s-Gravenhage"];
-        yield ['2594 BD', 10, "'s-Gravenhaagse Bos", "'s-Gravenhage"];
-    }
-
-    /**
-     * @dataProvider providePostcodeData
-     *
-     * This test actually calls the real API, so it can fail beyond our control.
-     */
-    public function testSearch(string $postcode, int $number, string $expectedStreet, string $expectedCity): void
-    {
-        $result = $this->client->get($postcode, $number);
-
-        self::assertEquals($expectedStreet, $result['street']);
-        self::assertEquals($expectedCity, $result['city']);
-    }
-}
diff --git a/tests/Http/Request/HeadersTest.php b/tests/Http/Request/HeadersTest.php
deleted file mode 100644
index 5fabecd..0000000
--- a/tests/Http/Request/HeadersTest.php
+++ /dev/null
@@ -1,22 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Http\Request;
-
-use Kkevindev\PostcodeTech\Http\Request\Headers;
-use PHPUnit\Framework\TestCase;
-
-final class HeadersTest extends TestCase
-{
-    public function testAddAndGetHeaders(): void
-    {
-        $headers = new Headers(['Authorization' => 'Bearer demo']);
-
-        self::assertEquals("Authorization: Bearer demo\r\n", $headers->getHeaders());
-
-        $headers->addHeader('Content-Type', 'application/json');
-
-        self::assertEquals("Authorization: Bearer demo\r\nContent-Type: application/json\r\n", $headers->getHeaders());
-    }
-}
diff --git a/tests/Http/Response/HeadersTest.php b/tests/Http/Response/HeadersTest.php
deleted file mode 100644
index bb811c1..0000000
--- a/tests/Http/Response/HeadersTest.php
+++ /dev/null
@@ -1,31 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Http\Response;
-
-use Kkevindev\PostcodeTech\Http\Response\Headers;
-use PHPUnit\Framework\TestCase;
-
-final class HeadersTest extends TestCase
-{
-    public static function provideStatusCodes(): iterable
-    {
-        yield ['HTTP/1.1 200 OK', 200];
-        yield ['HTTP/1.1 404 Not Found', 404];
-        yield ['HTTP/1.1 422 Unprocessable Content', 422];
-        yield ['HTTP/1.1 500 Internal Server Error', 500];
-    }
-
-    /**
-     * @dataProvider provideStatusCodes
-     */
-    public function testGetStatusCode(string $statusCode, int $expectedStatusCode): void
-    {
-        $headers = new Headers([
-            0 => $statusCode,
-        ]);
-
-        self::assertEquals($expectedStatusCode, $headers->getStatusCode());
-    }
-}
diff --git a/tests/Http/Response/ResponseTest.php b/tests/Http/Response/ResponseTest.php
deleted file mode 100644
index 30aaf00..0000000
--- a/tests/Http/Response/ResponseTest.php
+++ /dev/null
@@ -1,70 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Http\Response;
-
-use Kkevindev\PostcodeTech\Exceptions\HttpException;
-use Kkevindev\PostcodeTech\Http\Response\Response;
-use PHPUnit\Framework\TestCase;
-
-final class ResponseTest extends TestCase
-{
-    public static function provideStatusCodes(): iterable
-    {
-        yield [200, true];
-        yield [404, false];
-        yield [422, false];
-        yield [500, false];
-    }
-
-    /**
-     * @dataProvider provideStatusCodes
-     */
-    public function testIsSuccess(int $statusCode, bool $expectedIsSuccess): void
-    {
-        $response = new Response('', [0 => sprintf('HTTP/1.1 %s', $statusCode)]);
-
-        self::assertEquals($expectedIsSuccess, $response->isSuccess());
-    }
-
-    public function testGetResponseBodyAsArrayThrowsExceptionForInvalidJsonArray(): void
-    {
-        self::expectException(HttpException::class);
-        self::expectExceptionMessage('The response body is not a valid JSON array.');
-
-        $response = new Response('', []);
-        $response->getResponseBodyAsArray();
-    }
-
-    public static function provideInvalidJsonResponseBodies(): iterable
-    {
-        yield ['{}'];
-        yield ['{"street": "", "city": ""}'];
-        yield ['{"city": ""}'];
-        yield ['{"street": "", "city": ""}'];
-        yield ['{"street": "non-empty", "city": ""}'];
-        yield ['{"street": "", "city": "non-empty"}'];
-    }
-
-    /**
-     * @dataProvider provideInvalidJsonResponseBodies
-     */
-    public function testGetResponseBodyAsArrayThrowsExceptionForInvalidJsonArrayStructure(string $responseBody): void
-    {
-        self::expectException(HttpException::class);
-        self::expectExceptionMessage('The response body did not contain the expected data.');
-
-        $response = new Response($responseBody, []);
-        $response->getResponseBodyAsArray();
-    }
-
-    public function testGetResponseBodyAsArrayReturnsArray(): void
-    {
-        $response = new Response('{"street": "straat", "city": "stad"}', []);
-        $responseBodyArray = $response->getResponseBodyAsArray();
-
-        self::assertSame('straat', $responseBodyArray['street']);
-        self::assertSame('stad', $responseBodyArray['city']);
-    }
-}
diff --git a/tests/Integration/ClientTest.php b/tests/Integration/ClientTest.php
new file mode 100644
index 0000000..74a732f
--- /dev/null
+++ b/tests/Integration/ClientTest.php
@@ -0,0 +1,22 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Kkevindev\PostcodeTech\Tests\Integration;
+
+use Kkevindev\PostcodeTech\Client;
+use Kkevindev\PostcodeTech\Tests\AbstractClientTestCase;
+use Symfony\Component\HttpClient\HttpClient;
+
+/**
+ * This test actually calls the real API, so it can fail beyond our control.
+ *
+ * It serves as a check if our mocked data is still up-to-date.
+ */
+final class ClientTest extends AbstractClientTestCase
+{
+    protected function getClient(string $token): Client
+    {
+        return new Client($token, HttpClient::create());
+    }
+}
diff --git a/tests/PostcodeTest.php b/tests/Integration/PostcodeTest.php
similarity index 83%
rename from tests/PostcodeTest.php
rename to tests/Integration/PostcodeTest.php
index 4f99590..af17046 100644
--- a/tests/PostcodeTest.php
+++ b/tests/Integration/PostcodeTest.php
@@ -1,12 +1,20 @@
 <?php
 
-namespace Kkevindev\PostcodeTech\Tests;
+namespace Kkevindev\PostcodeTech\Tests\Integration;
 
 use Kkevindev\PostcodeTech\Postcode;
 use PHPUnit\Framework\TestCase;
 
 final class PostcodeTest extends TestCase
 {
+    /**
+     * @return iterable<array{
+     *     0: string,
+     *     1: int,
+     *     2: string,
+     *     3: string,
+     * }>
+     */
     public static function providePostcodeData(): iterable
     {
         yield ['1012 RJ', 147, 'Nieuwezijds Voorburgwal', 'Amsterdam'];
diff --git a/tests/Mock/MockResponseHttpClient.php b/tests/Mock/MockResponseHttpClient.php
new file mode 100644
index 0000000..46bcb22
--- /dev/null
+++ b/tests/Mock/MockResponseHttpClient.php
@@ -0,0 +1,50 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Kkevindev\PostcodeTech\Tests\Mock;
+
+use Kkevindev\AssertReturnValue\Assert;
+use Symfony\Component\HttpClient\MockHttpClient;
+use Symfony\Component\HttpClient\Response\MockResponse;
+
+final class MockResponseHttpClient extends MockHttpClient
+{
+    public function __construct()
+    {
+        parent::__construct(static function (string $method, string $url, array $options): MockResponse {
+            $url = parse_url($url);
+
+            $responseDir = sprintf('%s/%s', __DIR__, 'Responses');
+
+            $responseFileName = ltrim(
+                str_replace(
+                    '/',
+                    '_',
+                    sprintf(
+                        '%s_%s',
+                        Assert::stringNotEmpty($url['path'] ?? ''),
+                        Assert::stringNotEmpty($url['query'] ?? ''),
+                    ),
+                ),
+                '_',
+            );
+
+            $responseFilePath = sprintf('%s/%s', $responseDir, $responseFileName);
+            if (!file_exists($responseFilePath)) {
+                touch($responseFilePath);
+                exit(sprintf("Expected mock response file '%s' to exist.", $responseFilePath));
+            }
+
+            $meta = [];
+            if (file_exists($responseFilePath.'.meta')) {
+                $meta = parse_ini_file($responseFilePath.'.meta', false, INI_SCANNER_TYPED) ?: [];
+            }
+
+            return new MockResponse(
+                Assert::string(file_get_contents($responseFilePath)),
+                $meta,
+            );
+        });
+    }
+}
diff --git a/tests/Mock/Responses/api_v1_postcode_postcode=0000AA&number=401 b/tests/Mock/Responses/api_v1_postcode_postcode=0000AA&number=401
new file mode 100644
index 0000000..d1fa144
--- /dev/null
+++ b/tests/Mock/Responses/api_v1_postcode_postcode=0000AA&number=401
@@ -0,0 +1,3 @@
+{
+    "message": "Unauthorized"
+}
diff --git a/tests/Mock/Responses/api_v1_postcode_postcode=0000AA&number=401.meta b/tests/Mock/Responses/api_v1_postcode_postcode=0000AA&number=401.meta
new file mode 100644
index 0000000..295727f
--- /dev/null
+++ b/tests/Mock/Responses/api_v1_postcode_postcode=0000AA&number=401.meta
@@ -0,0 +1 @@
+http_code=401
diff --git a/tests/Mock/Responses/api_v1_postcode_postcode=0000AA&number=404 b/tests/Mock/Responses/api_v1_postcode_postcode=0000AA&number=404
new file mode 100644
index 0000000..57b15af
--- /dev/null
+++ b/tests/Mock/Responses/api_v1_postcode_postcode=0000AA&number=404
@@ -0,0 +1 @@
+{"message":"No result for this combination."}
diff --git a/tests/Mock/Responses/api_v1_postcode_postcode=0000AA&number=404.meta b/tests/Mock/Responses/api_v1_postcode_postcode=0000AA&number=404.meta
new file mode 100644
index 0000000..179aca0
--- /dev/null
+++ b/tests/Mock/Responses/api_v1_postcode_postcode=0000AA&number=404.meta
@@ -0,0 +1 @@
+http_code=404
diff --git a/tests/Mock/Responses/api_v1_postcode_postcode=1012%20RJ&number=147 b/tests/Mock/Responses/api_v1_postcode_postcode=1012%20RJ&number=147
new file mode 100644
index 0000000..518eb25
--- /dev/null
+++ b/tests/Mock/Responses/api_v1_postcode_postcode=1012%20RJ&number=147
@@ -0,0 +1 @@
+{"street":"Nieuwezijds Voorburgwal","city":"Amsterdam"}
diff --git a/tests/Mock/Responses/api_v1_postcode_postcode=X&number=422 b/tests/Mock/Responses/api_v1_postcode_postcode=X&number=422
new file mode 100644
index 0000000..3504cff
--- /dev/null
+++ b/tests/Mock/Responses/api_v1_postcode_postcode=X&number=422
@@ -0,0 +1 @@
+{"message":"The given data was invalid.","errors":{"postcode":["Postcode should be formatted `1111AA` or `1111 AA`."]}}
diff --git a/tests/Mock/Responses/api_v1_postcode_postcode=X&number=422.meta b/tests/Mock/Responses/api_v1_postcode_postcode=X&number=422.meta
new file mode 100644
index 0000000..0670f9f
--- /dev/null
+++ b/tests/Mock/Responses/api_v1_postcode_postcode=X&number=422.meta
@@ -0,0 +1 @@
+http_code=422
diff --git a/tests/Unit/ClientTest.php b/tests/Unit/ClientTest.php
new file mode 100644
index 0000000..66457ab
--- /dev/null
+++ b/tests/Unit/ClientTest.php
@@ -0,0 +1,17 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Kkevindev\PostcodeTech\Tests\Unit;
+
+use Kkevindev\PostcodeTech\Client;
+use Kkevindev\PostcodeTech\Tests\AbstractClientTestCase;
+use Kkevindev\PostcodeTech\Tests\Mock\MockResponseHttpClient;
+
+final class ClientTest extends AbstractClientTestCase
+{
+    protected function getClient(string $token): Client
+    {
+        return new Client($token, new MockResponseHttpClient());
+    }
+}

From cc1994c4d21db4651e92803dd9ec4ee4c2db2466 Mon Sep 17 00:00:00 2001
From: Kevin <34477826+kkevindev@users.noreply.github.com>
Date: Fri, 30 Jan 2026 20:53:11 +0100
Subject: [PATCH 2/2] Fixed invalid composer.json file.

---
 composer.json | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/composer.json b/composer.json
index e64fc72..1fc4227 100644
--- a/composer.json
+++ b/composer.json
@@ -5,7 +5,7 @@
     "type": "library",
     "require": {
         "php": "^8.1",
-        "kkevindev/assert-return-value":"1.11.0",
+        "kkevindev/assert-return-value":"^1.11.0",
         "symfony/http-client": "^6.4 || ^7.0 || ^8.0"
     },
     "require-dev": {
@@ -26,6 +26,7 @@
     "scripts": {
         "test": "vendor/bin/phpunit",
         "cs-fix": "vendor/bin/php-cs-fixer fix",
-        "phpstan": "vendor/bin/phpstan analyse"
+        "phpstan": "vendor/bin/phpstan analyse",
+        "composer-validate": "composer validate --strict"
     }
 }