文件上传冻结率为5％

Question

我有HTML / JavaScript（jQuery）和PHP来上传文件。在我的本地机器上测试时，一切都很完美。当我改变一些东西并将代码推送到服务器时，一切都有效，除了上传冻结率为5％。为什么要这样做？

PHP：

<?php

require_once("includes_sitewide/session.php");

function convert_date($date) {
  $s = split('\/', $date);
  return $s[2] . '_' . $s[0] . '_' . $s[1];
}

define('UPLOAD_FOLDER', 'uploads');

if (!isset($_SESSION['LOGGED_IN']) || !$_SESSION['LOGGED_IN']) {
  http_response_code(401);
  echo 'Unauthorized to upload files';
} else {
  if (!isset($_FILES['file'])) {
    http_response_code(500);
    echo 'No file data';
  } else if (!isset($_FILES['file']['error']) || is_array($_FILES['file']['error'])) {
    http_response_code(500);
    echo 'Unknown error';
  } else {
    switch ($_FILES['file']['error']) {
      case UPLOAD_ERR_OK:
        if (is_writable(UPLOAD_FOLDER)) {
          $filename = basename($_FILES['file']['name']);
          $target = UPLOAD_FOLDER . '/' . convert_date($_POST['date']) . '_' . time() . '_' . $filename;
          if (move_uploaded_file($_FILES['file']['tmp_name'], $target)) {
            if (
              file_put_contents($target . '.txt',
                "Name(s): " . $_POST['names'] .
                "\nTitle: " . $_POST['title'] .
                "\nDate: "  . $_POST['date'] .
                (isset($_POST['notes']) ? "\nNotes:\n" . $_POST['notes'] : ''))
              ) {
              echo $filename . ' uploaded sucessfully';
            } else {
              http_response_code(500);
              echo 'Failed to write notes file';
            }
          } else {
            http_response_code(500);
            echo 'Failed to save file as \'' . $target . '\'';
          }
        } else {
          http_response_code(500);
          echo 'Target folder \'' . UPLOAD_FOLDER . '\' is not writable';
        }
        break;
      case UPLOAD_ERR_NO_FILE:
        http_response_code(500);
        echo 'No input file';
        break;
      case UPLOAD_ERR_INI_SIZE:
      case UPLOAD_ERR_FORM_SIZE:
        http_response_code(500);
        echo 'Exceeded filesize limit!';
        break;
      default:
        http_response_code(500);
        echo 'Unknown error!';
    }
  }
}
?>

的JavaScript（jQuery的）：

var fileID = 0;
$('#form').submit(function() {
  // validation
  var ok = true;
  if (!$('input[name=file]').val()) {
    appendAlert('danger', 'Please select a file');
    ok = false;
  }
  var names = $('input[name=names]').val();
  if (!names) {
    appendAlert('danger', 'Please enter name(s)');
    ok = false;
  }
  var title = $('input[name=title]').val();
  if (!title) {
    appendAlert('danger', 'Please enter announcement title/group');
    ok = false;
  }
  var date = $('input[name=date]').val();
  if (!date) {
    appendAlert('danger', 'Please enter date');
    ok = false;
  } else if (!/^[0-1]\d\/[0-3]\d\/\d{4}$/.test(date)) {
    appendAlert('danger', 'Date must be in format mm/dd/yyyy');
    ok = false;
  } else {
    var bits = date.split('/');
    var d = new Date(bits[2], bits[0] - 1, bits[1]);
    if (!d || (d.getMonth() + 1) != bits[0] || d.getDate() != bits[1]) {
      appendAlert('danger', 'Date must be valid');
      ok = false;
    }
  }

  if (!ok) {
    return false;
  }

  fileID++;

  var file = $('input[name=file]').prop('files')[0];

  if (file.size > MAX_FILE_SIZE) {
    appendAlert('danger', 'File size too large (' + file.size + ' > ' + MAX_FILE_SIZE + ' bytes)');
    return false;
  }
  if (FILE_EXTENSIONS.indexOf(file.name.split('.').pop().toLowerCase()) == -1) {
    appendAlert('danger', file.name + ' has an invalid file extension');
    return false;
  }

  var fd = new FormData();
  fd.set('file', file);
  fd.set('names', names);
  fd.set('title', title);
  fd.set('date', date);
  var notes = $('input[name=notes]').val();
  if (notes) {
    fd.set('notes', notes);
  }

  $.ajax({
    type: 'POST',
    url: 'upload.php',
    data: fd,
    processData: false,
    contentType: false,
    success: function(data) {
      $('#progress-' + fileID + ' > .progress-bar').css('width', '100%').html('100%').addClass('progress-bar-success');
      appendAlert('success', data);
    },
    error: function(jqXHR, textStatus, errorThrown) {
      $('#progress-' + fileID + ' > .progress-bar').css('width', '100%').html('error').addClass('progress-bar-danger');
      appendAlert('danger', jqXHR.status + ' ' + errorThrown + ': "' + jqXHR.responseText + '"');
    },
    xhr: function() {
      var xhr = new window.XMLHttpRequest();
      xhr.upload.addEventListener('progress', function(e) {
        var x = 0;
        if (e.lengthComputable) {
          x = Math.floor(e.loaded / e.total * 100);
        }
        $('#progress-' + fileID + ' > .progress-bar').css('width', x + '%').html(x + "%");
      });
      return xhr;
    }
  });
  $('#file-table > tbody').append('<tr><td>' + fileID + '</td><td>' + file.name + '</td><td>' + file.size + ' bytes</td><td><div id="progress-' + fileID + '" class="progress" style="margin-bottom:0;"><div class="progress-bar" role="progressbar" style="width: 0;">0%</div></div></td></tr>');
  $('#progress').show();

  resetForm();

  return false;
});