feat: implement MySQL driver and API schema services for database management

backend/app/Contracts/DatabaseDriverInterface.php

@@ -33,4 +33,19 @@ interface DatabaseDriverInterface
      * Get the underlying connection instance.
      */
     public function getConnection();
+
+    /**
+     * Export the database.
+     */
+    public function export(array $config): string;
+
+    /**
+     * Import the database.
+     */
+    public function import(array $config, string $filePath): bool;
+
+    /**
+     * Get database metadata (charset, collation, size, etc.)
+     */
+    public function getDatabaseMetadata(string $database): array;
 }

backend/app/Http/Controllers/Api/SchemaController.php

@@ -104,4 +104,54 @@ class SchemaController extends Controller
             return Response::json(['error' => $e->getMessage()], 400);
         }
     }
+
+    public function export(Request $request)
+    {
+        try {
+            $this->initializeDriver($request);
+            $config = $request->only(['host', 'username', 'password', 'database', 'port']);
+            $filePath = $this->databaseService->export($config);
+            
+            return Response::download($filePath)->deleteFileAfterSend(true);
+        } catch (\Exception $e) {
+            return Response::json(['error' => $e->getMessage()], 400);
+        }
+    }
+
+    public function import(Request $request)
+    {
+        try {
+            if (!$request->hasFile('file')) {
+                return Response::json(['error' => 'No file uploaded'], 400);
+            }
+
+            $this->initializeDriver($request);
+            $config = $request->only(['host', 'username', 'password', 'database', 'port']);
+            
+            $file = $request->file('file');
+            $tempPath = $file->storeAs('temp', $file->getClientOriginalName());
+            $fullPath = storage_path('app/' . $tempPath);
+            
+            $this->databaseService->import($config, $fullPath);
+            
+            if (file_exists($fullPath)) {
+                unlink($fullPath);
+            }
+            
+            return Response::json(['message' => 'Database imported successfully']);
+        } catch (\Exception $e) {
+            return Response::json(['error' => $e->getMessage()], 400);
+        }
+    }
+
+    public function metadata(Request $request, $database)
+    {
+        try {
+            $request->merge(['database' => $database]);
+            $this->initializeDriver($request);
+            return Response::json($this->databaseService->getDatabaseMetadata($database));
+        } catch (\Exception $e) {
+            return Response::json(['error' => $e->getMessage()], 400);
+        }
+    }
 }

backend/app/Services/Database/MySqlDriver.php

@@ -93,4 +93,120 @@ class MySqlDriver implements DatabaseDriverInterface, SchemaDiscoveryInterface
         $dbName = DB::connection($this->connectionName)->getDatabaseName();
         return $this->query($sql, [$table, $dbName]);
     }
+
+    public function export(array $config): string
+    {
+        $filename = 'backup-' . ($config['database'] ?? 'all') . '-' . date('Y-m-d-H-i-s') . '.sql';
+        $directory = storage_path('app/backups');
+        
+        if (!is_dir($directory)) {
+            mkdir($directory, 0755, true);
+        }
+
+        $path = $directory . DIRECTORY_SEPARATOR . $filename;
+        $errorPath = $directory . DIRECTORY_SEPARATOR . $filename . '.err';
+        
+        // Ensure we have a username
+        $username = $config['username'] ?? 'root';
+        $password = $config['password'] ?? '';
+        $host = $config['host'] ?? '127.0.0.1';
+        $port = $config['port'] ?? '3306';
+        $database = $config['database'] ?? '';
+
+        // Build command
+        $passwordPart = !empty($password) ? "-p" . escapeshellarg($password) : "";
+        $dbPart = !empty($database) ? escapeshellarg($database) : "--all-databases";
+        
+        // On Windows, we might need to handle double quotes in escapeshellarg
+        // Let's use a more robust way to execute and capture errors
+        $command = sprintf(
+            'mysqldump -u %s %s -h %s -P %s %s > %s 2> %s',
+            escapeshellarg($username),
+            $passwordPart,
+            escapeshellarg($host),
+            escapeshellarg($port),
+            $dbPart,
+            escapeshellarg($path),
+            escapeshellarg($errorPath)
+        );
+
+        shell_exec($command);
+
+        if (file_exists($errorPath)) {
+            $errors = file_get_contents($errorPath);
+            unlink($errorPath);
+            if (!empty(trim($errors))) {
+                // If the file is 0 bytes and there are errors, it definitely failed
+                if (!file_exists($path) || filesize($path) === 0) {
+                    throw new \Exception("Export failed: " . $errors);
+                }
+            }
+        }
+
+        if (!file_exists($path) || filesize($path) === 0) {
+            throw new \Exception("Export failed: Resulting file is empty. Ensure mysqldump is installed and in the system PATH.");
+        }
+
+        return $path;
+    }
+
+    public function import(array $config, string $filePath): bool
+    {
+        $directory = storage_path('app/backups');
+        if (!is_dir($directory)) {
+            mkdir($directory, 0755, true);
+        }
+        $errorPath = $directory . DIRECTORY_SEPARATOR . 'import_error.err';
+
+        $username = $config['username'] ?? 'root';
+        $password = $config['password'] ?? '';
+        $host = $config['host'] ?? '127.0.0.1';
+        $port = $config['port'] ?? '3306';
+        $database = $config['database'] ?? '';
+
+        $passwordPart = !empty($password) ? "-p" . escapeshellarg($password) : "";
+        $dbPart = !empty($database) ? escapeshellarg($database) : "";
+
+        $command = sprintf(
+            'mysql -u %s %s -h %s -P %s %s < %s 2> %s',
+            escapeshellarg($username),
+            $passwordPart,
+            escapeshellarg($host),
+            escapeshellarg($port),
+            $dbPart,
+            escapeshellarg($filePath),
+            escapeshellarg($errorPath)
+        );
+
+        shell_exec($command);
+
+        if (file_exists($errorPath)) {
+            $errors = file_get_contents($errorPath);
+            unlink($errorPath);
+            if (!empty(trim($errors))) {
+                throw new \Exception("Import failed: " . $errors);
+            }
+        }
+
+        return true;
+    }
+
+    public function getDatabaseMetadata(string $database): array
+    {
+        $sql = "
+            SELECT 
+                s.DEFAULT_CHARACTER_SET_NAME as charset,
+                s.DEFAULT_COLLATION_NAME as collation,
+                (SELECT SUM(data_length + index_length) FROM information_schema.TABLES WHERE table_schema = s.SCHEMA_NAME) as size_bytes,
+                (SELECT COUNT(*) FROM information_schema.TABLES WHERE table_schema = s.SCHEMA_NAME) as table_count,
+                (SELECT COUNT(*) FROM information_schema.VIEWS WHERE table_schema = s.SCHEMA_NAME) as view_count
+            FROM 
+                information_schema.SCHEMATA s
+            WHERE 
+                s.SCHEMA_NAME = ?
+        ";
+
+        $results = $this->query($sql, [$database]);
+        return (array) ($results[0] ?? []);
+    }
 }

backend/app/Services/DatabaseService.php

@@ -98,4 +98,28 @@ class DatabaseService
     {
         return $this->getDriver()->query($sql, $bindings);
     }
+
+    /**
+     * Export the database.
+     */
+    public function export(array $config): string
+    {
+        return $this->getDriver()->export($config);
+    }
+
+    /**
+     * Import the database.
+     */
+    public function import(array $config, string $filePath): bool
+    {
+        return $this->getDriver()->import($config, $filePath);
+    }
+
+    /**
+     * Get database metadata.
+     */
+    public function getDatabaseMetadata(string $database): array
+    {
+        return $this->getDriver()->getDatabaseMetadata($database);
+    }
 }