ошибка загрузки файла (вложения)

Я получаю сообщение об ошибке при сохранении формы и сетки данных
Я не знаю, в чем ошибка?
Я использую extjs 4 и Zend Framework 2

это сообщение об ошибке:

sourceClass: "Ext.JSON",
sourceMethod: "decode",
msg: "You're trying to decode an invalid JSON String: Wa…session":true,
"other":null,"processingTime":null}",
message: "You're trying to decode an invalid JSON String: Wa…session":true,
"other":null,"processingTime":null}"}
message: "You're trying to decode an invalid JSON String:
Warning: Invalid argument supplied for foreach() in Purchase.php on line 331↵
{"success":false,"data":{"no_po":null,"date_po":null,"supplier":null,"shipping_to":null,"total_price_head":null,"vat":null,"net_price":null,"id_po":null,"file_ext":"png","file_type":"image\/png","file_size":633237,"file_name":"2015-02-23-Negative-World-left-hand.png"},"messages":[],"pageSize":null,"start":null,"total":null,"session":true,"other":null,"processingTime":null}"msg: "You're trying to decode an invalid JSON String:
Warning: Invalid argument supplied for foreach() in Purchase.php on line 331↵
{"success":false,"data":{"no_po":null,"date_po":null,"supplier":null,"shipping_to":null,"total_price_head":null,"vat":null,"net_price":null,"id_po":null,"file_ext":"png","file_type":"image\/png","file_size":633237,"file_name":"2015-02-23-Negative-World-left-hand.png"},"messages":[],"pageSize":null,"start":null,"total":null,"session":true,"other":null,"processingTime":null}"sourceClass: "Ext.JSON"sourceMethod: "decode"

и это мой код:

Purchase.php

public function savePurchaseOrder($header,$detail)
{
header('Content-Type: text/html');
try{

if(!$this->_user_id){
$this->result->messages[] = 'Session Expired, Please re-login';
return;
}

$_header = Zend_Json::decode($header, Zend_Json::TYPE_ARRAY);
$_detail = Zend_Json::decode($detail, Zend_Json::TYPE_ARRAY);

$userLogin = $this->_user_id;

$table_header = new Zend_Db_Table('vending_tr_purchase_product_order_id');
$table_detail = new Zend_Db_Table('vending_tr_purchase_product_order');
$table_detail_pr = new Zend_Db_Table('vending_tr_purchase_product');
//print_r($_detail);

if (isset($_FILES['file_path']))
{
$errors = array();
// define file attribute
$file_name = $_FILES['file_path']['name'];
$file_size = $_FILES['file_path']['size'];
$file_tmp  = $_FILES['file_path']['tmp_name'];
$file_type = $_FILES['file_path']['type'];
$file_ext  = strtolower(end(explode('.', $_FILES['file_path']['name'])));

$_newdata = array(
'no_po' => $_header['no_po'],
'date_po' => $_header['date_po'],
'supplier' => $_header['supplier'],
'shipping_to' => $_header['shipping_to'],
'total_price_head' => $_header['total_price_head'],
'vat' => $_header['vat'],
'net_price' => $_header['net_price'],
'id_po' => $_header['id_po'],
//'file_path' => $_header['file_path'],
'file_ext' => $file_ext,
'file_type' => $file_type,
'file_size' => $file_size,
'file_name' => $file_name

);

$ext = array(
"bmp",
"jpeg",
"jpg",
"png",
"gif",
"xls",
"xlsx",
"doc",
"docx",
"pdf",
"ppt",
"pptx",
"zip",
"rar",
"txt",
"rtf");
// check the extension type on upload process
if (in_array($file_ext, $ext) === false)
{
$errors[] = 'File format "' . $file_ext . '" is not allowed';
return $this->result->messages[] = $errors;
}
// check the file size is not more than 25 MB = 26214400 bytes, 1 MB = 1048576 bytes
if ($file_size > 26214400)
{
$errors[] = 'Sorry, the allowed max size is 25 MB';
return $this->result->messages[] = $errors;
}

if($_header['action'] == 'C'){
$record = array_merge($_newdata, array(
'row_created_by' => $userLogin,
'row_created_datetime' => date("YmdHis", strtotime($this->_datetime))
));
$table_header->insert($record);
$header_id = $this->_db->lastInsertId();
$this->result->success = true;
}

if($_header['action'] == 'U'){
$where = array("id_po = " . $this->_db->quote($_header['id_po']));
$record = array_merge($_newdata, array(
'row_changed_by' => $userLogin,
'row_changed_datetime' => date("YmdHis", strtotime($this->_datetime))
));
$table_header->update($record,$where);
$this->result->success = true;
}

foreach ($_detail as $key) {

$this->_db->beginTransaction();
//$key['data']['warehouse'] = $_header['warehouse'];

$_insertDetail = array(
'qty_order' => $key['data']['qty_order'],
'no_pr' => $key['data']['no_pr'],
'purchase_product_name' => $key['data']['purchase_product_name'],
'package' => $key['data']['package'],
'unit' => $key['data']['unit'],
'qty_approve' => $key['data']['qty_approve'],
'purchase_id_tr' => $key['data']['purchase_id_tr'],
'qty_hasil' => $key['data']['qty_hasil'],
'unit_price' => $key['data']['unit_price'],
'total_price' => $key['data']['total_price'],
'warehouse_name' => $key['data']['warehouse_name']
);

$_updateDetailPO = array(
'qty_order' => $key['data']['qty_order'],
'qty_hasil' => $key['data']['qty_hasil']
);

if($key['type'] == 'U'){
$where = array("purchase_id_tr = " . $this->_db->quote($key['data']['purchase_id_tr']));
$table_detail_pr->update($_updateDetailPO,$where);
$this->result->success = true;
}

if(!empty($key['data']['id'])){
$where = array("id = " . $this->_db->quote($key['data']['id']));
$table_detail->update($_insertDetail,$where);
$this->result->success = true;
}else{
$_insertDetail['id_po'] = $header_id;
$table_detail->insert($_insertDetail);
$this->_db->commit();
$updateStock = $this->updatePR($key['data']);
$this->result->success = true;
}

if($key['type'] == 'D'){
$where = array("id = " . $this->_db->quote($key['data']['id']));
$table_detail->delete($where);
$this->_db->commit();
$this->result->success = true;
}}
return $_newdata;

}}
catch(Exception $_e) {
$this->result->messages[] = new Sasmita_Transaction_Message('E', $_e->getMessage(), __CLASS__ . '/' . __FUNCTION__, __LINE__);
}
}

public function updatePR($data)
{
//var_dump($data);
//exit;
$_sStock = $this->_db->select('a vending_tr_purchase_product','*')
->where('a.purchase_id_tr = ?',$data['purchase_id_tr'])
//->where('a.warehouse_id = ?',$data['warehouse'])
->fetch();

$table = new Zend_Db_Table('vending_tr_purchase_product');

if(is_array($_sStock)){
$pengurangan = $data['qty_hasil']-$data['qty_order'];
$_updateDetailPO_R = array(
'qty_order' => $data['qty_order'],
'qty_hasil' => $pengurangan
);
$where = array("purchase_id_tr = " . $this->_db->quote($data['purchase_id_tr']));
$a = $table->update($_updateDetailPO_R,$where);
$this->result->success = true;
//print_r ($a);
//print_r($a->__toString());

}else{
$this->_db->beginTransaction();
$_insertArray = array(
'purchase_product_id' => $data['product_id'],
'brand' => $data['data']['brand'],
'package' => $data['data']['package'],
'purchase_product_name' => $data['data']['product_name'],
'qty_request' => $data['qty_request'],
'qty_approve' => $data['qty_approve'],
'qty_order' => $data['qty_approve'],
'qty_hasil' => $data['qty_approve'],
'approvel' => $data['approvel'],
'unit_price' => $data['unit_price'],
'unit' => $data['unit']
);
$table->insert($_insertArray);
$this->_db->commit();
$this->result->success = true;
}

return $this->result->success;
}

InputPO.js

requires: [
'Ext.form.Panel',
'Ext.form.FieldContainer',
'Ext.form.field.Date',
'Ext.form.field.File',
'Ext.form.field.Hidden',
'Ext.grid.Panel',
'Ext.toolbar.Toolbar',
'Ext.button.Button',
'Ext.toolbar.Separator',
'Ext.selection.CheckboxModel',
'Ext.form.field.Number',
'Ext.grid.column.Number',
'Ext.grid.column.Date',
'Ext.grid.column.Boolean',
'Ext.grid.View',
'Ext.grid.plugin.RowEditing',
'Ext.grid.feature.Summary'
],

fileUpload: true,
height: 473,
width: 633,
title: '',

initComponent: function() {
var me = this;

Ext.applyIf(me, {
items: [
{
xtype: 'form',
bodyPadding: 10,
title: '',
items: [
{
xtype: 'fieldcontainer',
fieldLabel: '',
layout: {
type: 'hbox',
align: 'stretch'
},
items: [
{
xtype: 'container',
items: [
{
xtype: 'textfield',
width: 250,
fieldLabel: 'No. PO',
labelWidth: 70,
name: 'no_po'
},
{
xtype: 'textfield',
hidden: true,
width: 250,
fieldLabel: 'ID. PO',
labelWidth: 70,
name: 'id_po'
},
{
xtype: 'datefield',
width: 250,
fieldLabel: 'Date',
labelWidth: 70,
name: 'date_po'
},
{
xtype: 'textfield',
width: 250,
fieldLabel: 'Supplier',
labelWidth: 70,
name: 'supplier'
}
]
},
{
xtype: 'container',
margin: '0 0 0 10',
items: [
{
xtype: 'textfield',
width: 250,
fieldLabel: 'Total Price',
labelWidth: 70,
name: 'total_price_head'
},
{
xtype: 'textfield',
width: 250,
fieldLabel: 'VAT',
labelWidth: 70,
name: 'vat'
},
{
xtype: 'textfield',
width: 250,
fieldLabel: 'Net Price',
labelWidth: 70,
name: 'net_price'
}
]
}
]
},
{
xtype: 'container',
items: [
{
xtype: 'textfield',
hidden: true,
width: 511,
fieldLabel: 'Shipping To',
labelWidth: 70,
name: 'shipping_to'
},
{
xtype: 'filefield',
width: 511,
fieldLabel: 'Attachment',
labelWidth: 70,
name: 'file_path'
}
]
},
{
xtype: 'hiddenfield',
name: 'action'
}
]
},
{
xtype: 'gridpanel',
height: 250,
itemId: 'detailProduct',
autoScroll: true,
bodyBorder: false,
title: 'Detail Product',
store: 'vending.purchase.DetailProduct',
dockedItems: [
{
xtype: 'toolbar',
dock: 'top',
items: [
{
xtype: 'button',
itemId: 'addDM',
iconCls: 'icon-add',
text: 'Add'
},
{
xtype: 'tbseparator'
},
{
xtype: 'button',
itemId: 'btnDelete_detailp',
iconCls: 'icon-delete',
text: 'Delete'
}
]
}
],
selModel: Ext.create('Ext.selection.CheckboxModel', {

}),
columns: [
{
xtype: 'gridcolumn',
dataIndex: 'purchase_id_tr',
text: 'Id'
},
{
xtype: 'gridcolumn',
hidden: true,
dataIndex: 'id_po',
text: 'Id'
},
{
xtype: 'gridcolumn',
dataIndex: 'warehouse_name',
text: 'Warehouse'
},
{
xtype: 'gridcolumn',
hidden: true,
dataIndex: 'qty_hasil',
text: 'Id'
},
{
xtype: 'gridcolumn',
dataIndex: 'no_pr',
text: 'No. PR'
},
{
xtype: 'gridcolumn',
dataIndex: 'purchase_product_name',
text: 'Product Name'
},
{
xtype: 'gridcolumn',
hidden: true,
dataIndex: 'string',
text: 'Brand'
},
{
xtype: 'gridcolumn',
hidden: true,
dataIndex: 'package',
text: 'Package'
},
{
xtype: 'gridcolumn',
hidden: true,
dataIndex: 'qty_approve',
text: 'Quantity Remaining'
},
{
xtype: 'gridcolumn',
dataIndex: 'unit',
text: 'Unit Order'
},
{
xtype: 'gridcolumn',
hidden: true,
dataIndex: 'qty_hasil',
text: 'Quantity Remaining'
},
{
xtype: 'gridcolumn',
dataIndex: 'qty_order',
text: 'Quantity',
editor: {
xtype: 'numberfield'
}
},
{
xtype: 'gridcolumn',
dataIndex: 'unit_price',
text: 'Unit Price',
editor: {
xtype: 'numberfield',
name: 'unit_price'
}
},
{
xtype: 'gridcolumn',
summaryType: 'sum',
dataIndex: 'total_price',
text: 'Total Price',
editor: {
xtype: 'numberfield',
name: 'total_price'
}
},
{
xtype: 'numbercolumn',
hidden: true,
dataIndex: 'number',
text: ''
},
{
xtype: 'datecolumn',
hidden: true,
dataIndex: 'date',
text: 'Date'
},
{
xtype: 'booleancolumn',
hidden: true,
dataIndex: 'bool',
text: 'Boolean'
}
],
plugins: [
Ext.create('Ext.grid.plugin.RowEditing', {
clicksToEdit: 1
})
],
features: [
{
ftype: 'summary'
}
]
},
{
xtype: 'gridpanel',
hidden: true,
title: 'Lokasi Pengiriman',
columns: [
{
xtype: 'gridcolumn',
dataIndex: 'string',
text: 'Nama gudang'
},
{
xtype: 'gridcolumn',
dataIndex: 'string',
text: 'Alamat'
},
{
xtype: 'gridcolumn',
dataIndex: 'string',
text: 'Shipping To'
},
{
xtype: 'numbercolumn',
hidden: true,
dataIndex: 'number',
text: 'Number'
},
{
xtype: 'datecolumn',
hidden: true,
dataIndex: 'date',
text: 'Date'
},
{
xtype: 'booleancolumn',
hidden: true,
dataIndex: 'bool',
text: 'Boolean'
}
]
}
]
});

me.callParent(arguments);
}

});

и это мой контроллер JS Action Нажмите кнопку Сохранить:

onButtonSave: function(button, e, eOpts) {

console.log("suksesss");
var me = this;
var _panel = me.getMainPanel();
var _tabpanel = _panel.down("#tabmaintain");
var _activetab = _tabpanel.getActiveTab();
var form = _activetab.down('form').getForm();
var values = form.getValues();
var myMask = new Ext.LoadMask(_activetab, {msg:"Please wait..."});if(form.isValid())
{
myMask.show();
form.submit({
url: '/jsonresult/Sasmita_Vending_Purchase/saveGoodsReceived',
success: function(fp, o) {
myMask.hide();
//me.fnReloadTabAttachment();
_activetab.close();
},
failure: function(fp,o){
myMask.hide();
if(!o.result.session)
{
Ext.Msg.alert('Error', o.result.messages);
}
else
{
if (o.result.messages[0].text)
{
Ext.Msg.alert('Error', o.result.messages[0].text);
}
else
{
Ext.Msg.alert('Error', o.result.messages);
}
}
}
});
}
},

Вот эта ошибка, когда foreach ..