Node.js (with express & bodyParser): unable to obtain form-data from post request

问题

I can\'t seem to recover the form-data of a post request sent to my Node.js server. I\'ve put below the server code and the post request (sent using postman in chrome):

Post request

POST /api/login HTTP/1.1
Host: localhost:8080
Cache-Control: no-cache

----WebKitFormBoundaryE19zNvXGzXaLvS5C
Content-Disposition: form-data; name=\"userName\"

jem
----WebKitFormBoundaryE19zNvXGzXaLvS5C

NodeJS server code

var express    = require(\'express\');        // call express
var app        = express();                 // define our app using express
var bodyParser = require(\'body-parser\');

app.use(bodyParser.urlencoded({ extended: true }));
app.use(bodyParser.json());
app.use(bodyParser());

app.all(\'/*\', function(req, res, next) {
    res.header(\'Access-Control-Allow-Origin\', \'*\');
    res.header(\'Access-Control-Allow-Headers\', \'Content-Type,accept,access_token,X-Requested-With\');
    next();
});

var port = process.env.PORT || 8080;        // set our port

var router = express.Router();              // get an instance of the express Router

router.get(\'/\', function(req, res) {

    res.json({ message: \'I am groot!\' });   
});

// Login
router.route(\'/login\')

    .post(function(req, res){

        console.log(\'Auth request recieved\');

        // Get the user name
        var user = req.body.userName;

        var aToken = getToken(user);

        res.json({

            \'token\':\'a_token\'
        });
    });

app.use(\'/api\', router);

app.listen(port);

The login method tries to obtain the req.body.userName, however, req.body is always empty. I\'ve seen other cases on SO describing such behavior but none of the related answers did apply here.

Thanks for helping out.

回答1:

In general, an express app needs to specify the appropriate body-parser middleware in order for req.body to contain the body.

[EDITED]

1. If you required parsing of url-encoded (non-multipart) form data, as well as JSON, try adding:

   // Put this statement near the top of your module
   var bodyParser = require('body-parser');
   
   
   // Put these statements before you define any routes.
   app.use(bodyParser.urlencoded());
   app.use(bodyParser.json());
   

   First, you'll need to add body-parser to the dependencies property of your package.json, and then perform a npm update.

2. To handle multi-part form data, the bodyParser.urlencoded() body parser will not work. See the suggested modules here for parsing multipart bodies.

回答2:

To handle multipart/form-data request that support file upload, you need to use multer module. npm link for multer middleware

回答3:

Make sure to put in this order: bodyParser.json() first. app.use(bodyParser.json()); app.use(bodyParser.urlencoded({ extended: true }));

来源：https://stackoverflow.com/questions/26347394/node-js-with-express-bodyparser-unable-to-obtain-form-data-from-post-reques