Getting this parameter on load in node js

this is what i get as error

TypeError: Cannot read property 'file' of undefined
    at C:\node\project\server.js:17:25
    at Layer.handle [as handle_request] (C:\node\node_modules\express\lib\router\layer.js:95:5)
    at next (C:\node\node_modules\express\lib\router\route.js:137:13)
    at Route.dispatch (C:\node\node_modules\express\lib\router\route.js:112:3)
    at Layer.handle [as handle_request] (C:\node\node_modules\express\lib\router\layer.js:95:5)
    at C:\node\node_modules\express\lib\router\index.js:281:22
    at Function.process_params (C:\node\node_modules\express\lib\router\index.js:335:12)
    at next (C:\node\node_modules\express\lib\router\index.js:275:10)
    at Immediate.<anonymous> (C:\node\node_modules\multer\lib\make-middleware.js:53:37)
    at runCallback (timers.js:670:20)

      

        
        
        
      

    

my html code

  <form action = "http://127.0.0.1:8081/file_upload" method = "POST" 
     enctype = "multipart/form-data">
     <input type="file" name="file" size="50" />
       <br />
     <input type = "submit" value = "Upload File" />
  </form>

      

        
        
        
      

    

my js code

console.log(req.file.file.name);
console.log(req.file.file.path);
console.log(req.file.file.type);
var file = __dirname + "/" + req.file.file.name;

      

        
        
        
      

    

where am i doing wrong?