Added SequentialCollection and updated readme

Author: bastianschwarz

README.md

@@ -37,6 +37,67 @@ code and leaves the rest to the build system that was running the checks:
 ```php
 <?php declare(strict_types=1);
 
+use de\codenamephp\deploymentchecks\base\Check\Result\WithExitCodeInterface;
+use de\codenamephp\deploymentchecks\base\ExitCode\DefaultExitCodes;
+use de\codenamephp\deploymentchecks\http\Check\HttpCheck;
+use de\codenamephp\deploymentchecks\http\Check\Test\StatusCode;
+use GuzzleHttp\Psr7\Request;
+
+require_once __DIR__ . '/../vendor/autoload.php';
+
+$result = (new HttpCheck(
+    new Request('GET', 'https://localhost/'),
+    'Frontpage should be available',
+    new StatusCode(200),
+))->run();
+
+exit($result instanceof WithExitCodeInterface ? $result->exitCode() : ($result->successful() ? DefaultExitCodes::SUCCESSFUL->value : DefaultExitCodes::ERROR->value));
+```
+
+This example uses the http package to perform http requests and run tests on them. It creates a single check with one test,
+runs it and checks the result. If it is a result with an exit code, the exit code is used. If not, the result is checked for success and
+the default exit codes are used.
+
+Since most CI/CD systems will run the script and check the exit code, this should already be enough to get the system to fail if one of the checks fail.
+
+It's very easy to run multiple checks:
+
+```php
+<?php declare(strict_types=1);
+
+use \de\codenamephp\deploymentchecks\base\Check\Collection\SequentialCollection;
+use de\codenamephp\deploymentchecks\base\Check\Result\WithExitCodeInterface;
+use de\codenamephp\deploymentchecks\base\ExitCode\DefaultExitCodes;
+use de\codenamephp\deploymentchecks\http\Check\HttpCheck;
+use de\codenamephp\deploymentchecks\http\Check\Test\StatusCode;
+use GuzzleHttp\Psr7\Request;
+
+require_once __DIR__ . '/../vendor/autoload.php';
+
+$result = (new SequentialCollection(
+  new HttpCheck(
+    new Request('GET', 'https://localhost'),
+    'Frontpage should be available',
+    new StatusCode(200),
+  ),
+  new HttpCheck(
+    new Request('GET', 'https://localhost/admin'),
+    'Admin login page should be available',
+    new StatusCode(401),
+  )
+))->run();
+
+exit($result instanceof WithExitCodeInterface ? $result->exitCode() : ($result->successful() ? DefaultExitCodes::SUCCESSFUL->value : DefaultExitCodes::ERROR->value));
+```
+
+Not much has changed. The only difference is that the checks are now wrapped in a collection that will run them sequentially. If one fails, the result will be
+unsuccessful.
+
+It's also very easy to run checks in parallel. The next example uses the async package to run the checks in parallel:
+
+```php
+<?php declare(strict_types=1);
+
 use de\codenamephp\deploymentchecks\async\Collection\AsyncCheckCollection;
 use de\codenamephp\deploymentchecks\base\Check\Result\WithExitCodeInterface;
 use de\codenamephp\deploymentchecks\base\ExitCode\DefaultExitCodes;
@@ -62,8 +123,4 @@ $result = (new AsyncCheckCollection(new \Spatie\Async\Pool(),
 exit($result instanceof WithExitCodeInterface ? $result->exitCode() : ($result->successful() ? DefaultExitCodes::SUCCESSFUL->value : DefaultExitCodes::ERROR->value));
 ```
 
-This example uses the http package to perform http requests and run tests on them together with the async package to the requests are tested in parallel.
-At the end the result is checked. If it is a result with an exit code, the exit code is used. If not, the result is checked for success and
-the default exit codes are used.
-
-Since most CI/CD systems will run the script and check the exit code, this should already be enough to get the system to fail if one of the checks fail.
+Again, not much has changed. The only difference is that the checks are now wrapped in a collection that will run them in parallel.

src/Check/Collection/SequentialCollection.php

@@ -0,0 +1,45 @@
+<?php declare(strict_types=1);
+/*
+ *  Copyright 2023 Bastian Schwarz <bastian@codename-php.de>.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+namespace de\codenamephp\deploymentchecks\base\Check\Collection;
+
+use de\codenamephp\deploymentchecks\base\Check\CheckInterface;
+use de\codenamephp\deploymentchecks\base\Check\Result\Collection\ResultCollection;
+use de\codenamephp\deploymentchecks\base\Check\Result\Collection\ResultCollectionInterface;
+use de\codenamephp\deploymentchecks\base\Check\Result\ResultInterface;
+
+/**
+ * Collects multiple checks and executes them sequentially and adds their results to a result collection
+ */
+final class SequentialCollection implements CheckInterface {
+
+  public readonly array $checks;
+
+  public ResultCollectionInterface $resultCollection;
+
+  public function __construct(CheckInterface ...$checks) {
+    $this->checks = $checks;
+    $this->resultCollection = new ResultCollection();
+  }
+
+  public function run() : ResultInterface {
+    foreach($this->checks as $check) {
+      $this->resultCollection->add($check->run());
+    }
+    return $this->resultCollection;
+  }
+}