Graceful cache fallback when cache driver is unreachable

src/BoostServiceProvider.php

@@ -47,17 +47,18 @@ public function register(): void
             $cacheKey = 'boost.roster.scan';
             $lastModified = max(array_map(fn (string $path): int|false => file_exists($path) ? filemtime($path) : 0, $lockFiles));
 
-            $cached = cache()->get($cacheKey);
+            $cached = rescue(fn () => cache()->get($cacheKey), report: false);
 
             if ($cached && isset($cached['timestamp']) && $cached['timestamp'] >= $lastModified) {
                 return $cached['roster'];
             }
 
             $roster = Roster::scan(base_path());
-            cache()->put($cacheKey, [
+
+            rescue(fn () => cache()->put($cacheKey, [
                 'roster' => $roster,
                 'timestamp' => time(),
-            ], now()->addHours(24));
+            ], now()->addHours(24)), report: false);
 
             return $roster;
         });

src/Mcp/Tools/DatabaseSchema.php

@@ -63,12 +63,16 @@ public function handle(Request $request): Response
             (int) $includeRoutines
         );
 
-        $schema = Cache::remember($cacheKey, 20, fn (): array => $this->getDatabaseStructure(
-            $connection,
-            $filter,
-            $includeViews,
-            $includeRoutines
-        ));
+        $schema = rescue(
+            fn () => Cache::remember($cacheKey, 20, fn (): array => $this->getDatabaseStructure(
+                $connection,
+                $filter,
+                $includeViews,
+                $includeRoutines
+            )),
+            fn (): array => $this->getDatabaseStructure($connection, $filter, $includeViews, $includeRoutines),
+            report: false
+        );
 
         return Response::json($schema);
     }

src/Mcp/Tools/LastError.php

@@ -29,12 +29,12 @@ public function __construct()
         if (! self::$listenerRegistered) {
             Log::listen(function (MessageLogged $event): void {
                 if ($event->level === 'error') {
-                    Cache::forever('boost:last_error', [
+                    rescue(fn () => Cache::forever('boost:last_error', [
                         'timestamp' => now()->toDateTimeString(),
                         'level' => $event->level,
                         'message' => $event->message,
                         'context' => [], // $event->context,
-                    ]);
+                    ]), report: false);
                 }
             });
 
@@ -54,7 +54,7 @@ public function handle(Request $request): Response
     {
         // First, attempt to retrieve the cached last error captured during runtime.
         // This works even if the log driver isn't a file driver, so is the preferred approach
-        $cached = Cache::get('boost:last_error');
+        $cached = rescue(fn () => Cache::get('boost:last_error'), report: false);
 
         if ($cached) {
             $entry = "[{$cached['timestamp']}] {$cached['level']}: {$cached['message']}";

tests/Feature/Mcp/Tools/DatabaseSchemaTest.php

@@ -58,6 +58,22 @@
         });
 });
 
+test('it falls back to direct query when cache is unreachable', function (): void {
+    Cache::shouldReceive('remember')
+        ->andThrow(new RuntimeException('Cache driver unreachable'));
+
+    $tool = new DatabaseSchema;
+    $response = $tool->handle(new Request([]));
+
+    expect($response)->isToolResult()
+        ->toolHasNoError()
+        ->toolJsonContent(function (array $schemaArray): void {
+            expect($schemaArray)->toHaveKey('engine')
+                ->and($schemaArray)->toHaveKey('tables')
+                ->and($schemaArray['tables'])->toHaveKey('examples');
+        });
+});
+
 test('it filters tables by name', function (): void {
     Schema::create('users', function (Blueprint $table): void {
         $table->id();

tests/Feature/Mcp/Tools/LastErrorTest.php

@@ -117,6 +117,29 @@
         ->toolTextContains('Daily driver error');
 });
 
+it('falls back to log file when cache is unreachable', function (): void {
+    Cache::shouldReceive('get')
+        ->with('boost:last_error')
+        ->andThrow(new RuntimeException('Cache driver unreachable'));
+
+    $logFile = storage_path('logs'.DIRECTORY_SEPARATOR.'laravel.log');
+
+    Config::set('logging.default', 'single');
+    Config::set('logging.channels.single', [
+        'driver' => 'single',
+        'path' => $logFile,
+    ]);
+
+    File::put($logFile, '[2024-01-15 10:00:00] local.ERROR: Fallback error from log file');
+
+    $tool = new LastError;
+    $response = $tool->handle(new Request([]));
+
+    expect($response)->isToolResult()
+        ->toolHasNoError()
+        ->toolTextContains('Fallback error from log file');
+});
+
 it('does not return info or warning entries', function (): void {
     $logFile = storage_path('logs'.DIRECTORY_SEPARATOR.'laravel.log');