Bug: Node Buffers less than 8192 bytes

[jerfowler]

When passing a small "unsafe" node buffer to Axios that is less than the size of Buffer.poolSize which is 8192 bytes, axios passes the entire 8192 bytes in the pool which can contain random data.

    var buf = new Buffer(1024); // Unsafe buffer < Buffer.poolSize (8192 bytes)
    buf.fill('x');

--or --

    var buf = Buffer.allocUnsafe(1024).fill('x'); // Unsafe buffer < Buffer.poolSize (8192 bytes)

Buffer.allocUnsafe(size)

Use of this pre-allocated internal memory pool is a key difference between calling Buffer.alloc(size, fill) vs. Buffer.allocUnsafe(size).fill(fill). Specifically, Buffer.alloc(size, fill) will never use the internal Buffer pool, while Buffer.allocUnsafe(size).fill(fill) will use the internal Buffer pool if size is less than or equal to half Buffer.poolSize. The difference is subtle but can be important when an application requires the additional performance that Buffer.allocUnsafe() provides.

Here is a test to reproduce the issue:

  testBuffer: function(test) {
    var buf = new Buffer(1024); // Unsafe buffer < Buffer.poolSize (8192 bytes)
    buf.fill('x');
    server = http.createServer(function (req, res) {
      test.equal(req.headers['content-length'], buf.length.toString());
      req.pipe(res);
    }).listen(4444, function () {
      axios.post('http://localhost:4444/',
        buf, {
        responseType: 'stream'
      }).then(function (res) {
        var stream = res.data;
        var string = '';
        stream.on('data', function (chunk) {
          string += chunk.toString('utf8');
        });
        stream.on('end', function () {
          test.equal(string, buf.toString());
          test.done();
        });
      });
    });
  },

Pull Request w/ test: #773

[nickuraltsev]

Fixed via #773