php - 在 Laravel 中创建备份 Controller

Question

我没有编程经验。我正在尝试在 laravel 中创建一个备份表的 Controller 。这些表已正确备份，但我收到一些评论说我的代码很容易被破坏。我一直在努力做到最好，但我真的很累，而且很沮丧。 我有一个表，表中的每一行占用 1 到 10 MB 的内存。表 100 中的总行数。最大内存量 (memory_limit) 设置为 35 MB。 解决此问题的最佳方法是什么？我真的很感谢任何建议或帮助。这是我的代码:

1. BackupController 类

   <?php
   namespace App\Http\Controllers;
   
   use Illuminate\Http\Request;
   use Illuminate\Support\Facades\Storage;
   use Illuminate\Database\Events\StatementPrepared; // set the fetch mode
   use Illuminate\Support\Facades\Cache;
   use Carbon\Carbon;
   use Illuminate\Support\Facades\Schema;
   use DB;
   use App\Post;
   use App\User;
   use App\Jobs\BackupTableJob;
   use Artisan;
   
   class BackupController extends Controller
   {
       const MAX_VALUE = 35000; //kilobytes 
   
       public function lockTable()
       {
           // lock all tables
           DB::unprepared('FLUSH TABLES WITH READ LOCK;');
       }
   
       public function setQueueJob(User $user, Post $post)
       {
           BackupTableJob::dispatch($user, $post)
               ->delay(Carbon::now()
               ->addSeconds(5));
           // Artisan::call('queue:work');     
       }
   
       public function unlockTable()
       {
           // unlock all tables
           DB::unprepared('UNLOCK TABLES');
       }
   
       public function queryFetch($data)
       {
           $pdo  = DB::connection()->getPdo();
           $stmt = $pdo->prepare($data);
           $stmt->execute();
           // $stmt = $pdo->query($data);
           $results = $stmt->fetch();
           return $results;
       }
   
       public function create(Request $request)
       {
           $this->setPdoMode();
           $numTables = DB::select("SHOW TABLES");
           $countUserRecords = User::count();
           $countPostRecords = Post::count();
   
           return view('backup', compact('numTables','countUserRecords', 'countPostRecords'));
       }
   
       public function setPdoMode()
       {
           \Event::listen(StatementPrepared::class, function($event) {
           $event->statement->setFetchMode(\PDO::FETCH_ASSOC);});
       }
   
       // public function backup(Request $request, User $user, Post $post)
       public function backup(Request $request, User $user, Post $post)
       {
          $this->setQueueJob($user, $post);          
          if ($request->all()) {
              $tables = request('table');
              $output = '';     
              foreach ($tables as $key => $table) {  
                  $this->lockTable();
                  $show_table_query = $this->queryFetch("SHOW CREATE TABLE {$table}");
                  $output .="\n" . $show_table_query[1] . ";\n";
                  $this->setPdoMode();
                  $single_result = DB::select("SELECT * FROM {$table}");
                  $output .= $this->getTableData($single_result, $table);
                  $output .= $this->cacheData($table, $output); 
              }
              if ($this->checkFileSize($output)) {
                  return redirect()->route('create'); 
              }                  
           }             
           return redirect()->route('backupError'); 
       }
   
       // Stores the file in this location: storage/app
       public function download($output)
       {
           $dt = Carbon::now();
           $file_name = 'backup_on[' . $dt->format('y-m-d H-i-s') . '].sql';
           Storage::disk('local')->put($file_name, $output);
       }
   
       public function getTableData($single_result, $table) 
       {
           $this->unlockTable();
           $output = '';
           foreach ($single_result as $key => $table_val) {
               if ($table === "posts" || $table === "users") {
                   $output .= "\nINSERT INTO $table("; 
                   $output .= "" .addslashes(implode(", ", array_keys($table_val))) . ") VALUES(";
                   $output .= "'" . addslashes(implode("','", array_values($table_val))) . "');\n";
               }  
           }
           // $output .= $this->cacheData($table, $output);   
           return $output;
       }
   
       public function checkFileSize($file)
       {
           $file_size = strlen($file);
           // convert bytes to kilobytes 
           $file_size = round($file_size / 1024, 0, PHP_ROUND_HALF_UP);
           if ($file_size <= self::MAX_VALUE) {
               $this->download($file);
               return true;
           } 
           return false;               
       }
   
       public function cacheData($table, $data)
       {
           // $table = $table;
           $start = microtime(true);
           $data = Cache::remember('table', 10, function() use ($table){
               return DB::table($table)->get();
           });
           $duration = (microtime(true) -$start) * 1000;
   
           \Log::info("From cache: " . $duration .' ms');
           return $data;
       }
    }
   

2. BackupTableJob 类

   <?php
   
   namespace App\Jobs;
   
   use App\User;
   use App\Post;
   use App\Http\Controllers\BackupController;
   use Illuminate\Http\Request;
   
   use Illuminate\Bus\Queueable;
   use Illuminate\Queue\SerializesModels;
   use Illuminate\Queue\InteractsWithQueue;
   use Illuminate\Contracts\Queue\ShouldQueue;
   use Illuminate\Foundation\Bus\Dispatchable;
   
   class BackupTableJob implements ShouldQueue
   {
       use Dispatchable, InteractsWithQueue, Queueable; //SerializesModels;
   
       protected $user;
       protected $post;
   
       /**
        * Create a new job instance.
        *
        * @return void
        */
       public function __construct(User $user, Post $post)
       // public function __construct()
       {
           $this->user = $user;
           $this->post = $post;
       }
   
       /**
        * Execute the job.
        *
        * @return void
        */
       public function handle()
       {
           // $this->user->save();
           // $this->post->save();
       }
   }
   

Answer 1

您不需要使用 PHP 处理该数据。您可以简单地在 Laravel 中使用原始 SQL 查询:

SELECT *
INTO tableToBeBackedUp
FROM currentTable;