♻️ Rename Dependency to Check for clarity (#9)

Conductor describes dependency checks, this implementation should be consistent with that naming.

src/Laravel/CollectsApplicationDependencyChecks.php

@@ -0,0 +1,30 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Shrink\Conductor\Laravel;
+
+use Shrink\Conductor\ChecksDependencyStatus;
+
+interface CollectsApplicationDependencyChecks
+{
+    /**
+     * @return array<string,\Shrink\Conductor\ChecksDependencyStatus>
+     */
+    public function listDependencyChecks(): array;
+
+    /**
+     * @throws \InvalidArgumentException
+     */
+    public function dependencyCheckById(string $id): ChecksDependencyStatus;
+
+    public function isDependencyCheckRegistered(string $id): bool;
+
+    /**
+     * @throws \InvalidArgumentException
+     */
+    public function addDependencyCheck(
+        string $id,
+        ChecksDependencyStatus $check
+    ): void;
+}

src/Laravel/Conductor.php

@@ -9,37 +9,55 @@
 use Illuminate\Routing\Router;
 use Illuminate\Routing\RouteRegistrar;
 use Illuminate\Support\ServiceProvider;
+use Lcobucci\Clock\Clock;
+use Shrink\Conductor\AggregateDependency;
 use Shrink\Conductor\Laravel\Dependencies\DatabaseSchema;
-use Shrink\Conductor\Laravel\Http\AttachDependencyParameter;
+use Shrink\Conductor\Laravel\Http\AttachDependencyCheckParameter;
 use Shrink\Conductor\Laravel\Http\ShowStatus;
 
 final class Conductor extends ServiceProvider
 {
     public function boot(Application $app, RouteRegistrar $registrar): void
     {
+        /** @psalm-var \Lcobucci\Clock\Clock */
+        $clock = $app->make(Clock::class);
+
+        $app->instance(
+            CollectsApplicationDependencyChecks::class,
+            $checks = new DependencyChecksArray()
+        );
+
+        $this->registerDatabaseChecks($app, $checks);
+
+        $checks->addDependencyCheck(
+            'application',
+            new AggregateDependency($clock, $checks->listDependencyChecks())
+        );
+
+        $this->registerHttpEndpoints($app, $registrar);
+    }
+
+    private function registerDatabaseChecks(
+        Application $app,
+        CollectsApplicationDependencyChecks $checks
+    ): void {
         $app->bind(Migrator::class, 'migrator');
 
         $app->when(DatabaseSchema::class)
             ->needs('$migrationsPath')
             ->give((string) $app->basePath('database/migrations'));
 
         /** @psalm-var \Shrink\Conductor\Laravel\Dependencies\DatabaseSchema */
-        $databaseSchemaDependency = $app->make(DatabaseSchema::class);
+        $databaseSchemaCheck = $app->make(DatabaseSchema::class);
 
-        $dependencies = new DependenciesArray(
-            new Dependency('database', $databaseSchemaDependency)
-        );
-
-        $app->instance(CollectsApplicationDependencies::class, $dependencies);
-
-        $this->registerHttpEndpoints($app, $registrar);
+        $checks->addDependencyCheck('schema', $databaseSchemaCheck);
     }
 
     private function registerHttpEndpoints(
         Application $app,
         RouteRegistrar $registrar
     ): void {
-        $app->when(AttachDependencyParameter::class)
+        $app->when(AttachDependencyCheckParameter::class)
             ->needs('$parameter')
             ->give('dependency');
 
@@ -48,7 +66,7 @@ private function registerHttpEndpoints(
         };
 
         $registrar
-            ->middleware(AttachDependencyParameter::class)
+            ->middleware(AttachDependencyCheckParameter::class)
             ->prefix('.conductor')
             ->group($endpoints);
     }

src/Laravel/DependencyChecksArray.php

@@ -0,0 +1,62 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Shrink\Conductor\Laravel;
+
+use InvalidArgumentException;
+use Shrink\Conductor\ChecksDependencyStatus;
+use function array_key_exists;
+use function preg_match;
+
+final class DependencyChecksArray implements CollectsApplicationDependencyChecks
+{
+    /**
+     * @var array<string,\Shrink\Conductor\ChecksDependencyStatus>
+     */
+    private array $checks = [];
+
+    /**
+     * @return array<string,\Shrink\Conductor\ChecksDependencyStatus>
+     */
+    public function listDependencyChecks(): array
+    {
+        return $this->checks;
+    }
+
+    /**
+     * @throws \InvalidArgumentException
+     */
+    public function dependencyCheckById(string $id): ChecksDependencyStatus
+    {
+        if (! $this->isDependencyCheckRegistered($id)) {
+            throw new InvalidArgumentException(<<<EXCEPTION
+            Dependency check not found for ID {$id}
+            EXCEPTION);
+        }
+
+        return $this->checks[$id];
+    }
+
+    public function isDependencyCheckRegistered(string $id): bool
+    {
+        return array_key_exists($id, $this->checks);
+    }
+
+    /**
+     * @throws \InvalidArgumentException
+     */
+    public function addDependencyCheck(
+        string $id,
+        ChecksDependencyStatus $check
+    ): void {
+        if (preg_match('%^[\w-]{1,32}$%', $id) !== 1) {
+            throw new InvalidArgumentException(<<<EXCEPTION
+            Dependency ID must be 1 to 32 word characters (ASCII letter, digit,
+            underscore or hyphen) in length
+            EXCEPTION);
+        }
+
+        $this->checks[$id] = $check;
+    }
+}

src/Laravel/Http/AttachDependencyParameter.php → src/Laravel/Http/AttachDependencyCheckParameter.php

@@ -5,28 +5,28 @@
 namespace Shrink\Conductor\Laravel\Http;
 
 use Illuminate\Http\Request;
-use Shrink\Conductor\Laravel\CollectsApplicationDependencies;
+use Shrink\Conductor\Laravel\CollectsApplicationDependencyChecks;
 use Symfony\Component\HttpFoundation\Response;
 
-final class AttachDependencyParameter
+final class AttachDependencyCheckParameter
 {
-    private CollectsApplicationDependencies $dependencies;
+    private CollectsApplicationDependencyChecks $checks;
 
     /**
-     * Name of the route parameter to attach the dependency to.
+     * Name of the route parameter to attach the check to.
      */
     private string $parameter;
 
     public function __construct(
-        CollectsApplicationDependencies $dependencies,
+        CollectsApplicationDependencyChecks $checks,
         string $parameter
     ) {
-        $this->dependencies = $dependencies;
+        $this->checks = $checks;
         $this->parameter = $parameter;
     }
 
     /**
-     * Find dependency by identifier from parameter and attach dependency to
+     * Find dependency check by identifier from parameter and attach check to
      * route as a parameter.
      */
     public function handle(Request $request, callable $next): Response
@@ -42,11 +42,11 @@ public function handle(Request $request, callable $next): Response
         /** @psalm-var string */
         $id = $route->parameter($this->parameter);
 
-        $dependency = $this->dependencies->dependencyById(
+        $check = $this->checks->dependencyCheckById(
             (string) $id
         );
 
-        $route->setParameter($this->parameter, $dependency);
+        $route->setParameter($this->parameter, $check);
 
         /** @psalm-var \Symfony\Component\HttpFoundation\Response */
         return $next($request);

src/Laravel/Http/ShowStatus.php

@@ -6,33 +6,28 @@
 
 use DateTimeInterface;
 use Illuminate\Http\JsonResponse;
-use Shrink\Conductor\Laravel\Dependency;
+use Shrink\Conductor\ChecksDependencyStatus;
 
 final class ShowStatus
 {
     /**
      * Execute a dependency check and create an HTTP Response using a status
-     * code to represent the state of the check.
+     * code to represent the status of the check.
      */
-    public function __invoke(Dependency $dependency): JsonResponse
+    public function __invoke(ChecksDependencyStatus $check): JsonResponse
     {
-        $status = $dependency->status();
-
-        $results = [
-            1 => ['pass', 200],
-            0 => ['fail', 503],
-        ];
-
-        [$label, $code] = $results[(int) $status->hasStatusCheckPassed()];
+        $status = $check->dependencyStatus();
 
         $description = [
-            'dependency' => $dependency->id(),
-            'status' => $label,
+            'status' => $status->hasStatusCheckPassed() ? 'pass' : 'fail',
             'checkedAt' => $status
                 ->statusCheckedAt()
                 ->format(DateTimeInterface::ATOM),
         ];
 
-        return new JsonResponse($description, $code);
+        return new JsonResponse(
+            $description,
+            $status->hasStatusCheckPassed() ? 200 : 503
+        );
     }
 }