Uploading Additional Data in HTML5/Flash Uploader PHP

Supported technologies: Adobe FlashHTML 5

Quite often it is necessary to send additional information along with files. HTML5/Flash Uploader solves this task and supports uploading the following kinds of additional information:

  • common information about upload defined by the Web site logic, such as an author name, keywords, or a category caption
  • a simple text description
  • image rotation angle
  • more image-specific information, like copyright notes and camera parameters during capturing, contained in EXIF and IPTC fields

This topic has two paragraphs, namely, uploading common data and uploading image-specific data. Each of them describes approaches on how to send and receive relevant data, possibilities provided by these approaches, and code samples.

Note

If you are unfamiliar with the Saving Uploaded Files in HTML5/Flash Uploader PHP topic, please, read it first.

Uploading Common Data

This section describes several approaches to uploading additional data. They are quite different but have two features in common, namely, independence of file types and upload of common data.

  • To get user-provided information about a whole upload you may use an HTML form, as described in the using additional HTML form section. This approach is simple to use and understand, it is also quite flexible. Pay attention to the fact that in this case you cannot upload different data for different files, only one set of data for a whole upload.
  • To add hidden data to a whole upload you can use custom fields. As opposed to the previous method, this one allows you to add data programmatically. For more information about this approach, see the using additional field section.
  • To upload user-defined file descriptions you do not need to configure HTML5/Flash Uploader beforehand, so it is the simplest way to get additional information with each uploaded file. Receiving of descriptions is examined in the using descriptions section.

Using Additional HTML Form

Using HTML forms is the most straight-forward way to upload data in web applications, thus, HTML5/Flash Uploader supports it. All you need is just to add the desired form to the same page where the ImageUploaderFlash class instance is hosted and set the Metadata.AdditionalFormName property to the name of created form. Then, when a user clicks Upload, the form data will be submitted along with user-selected files. On the server side, the fields of this form are accessible through the Package.PackageFields collection by their names.

An additional form can contain HTML input elements of different types, for example, you may use:

  • text for author's name
  • checkbox to determine whether to send a notification about the upload completion or not
  • select to choose keywords related to the upload
Note

The following input types are not allowed: file, image, button, and reset. Their values will not be sent at all.

Sending Data

The following configuration makes HTML5/Flash Uploader sending data from the addForm form along with uploaded files.

PHP
<form id="addForm" name="addForm">
    <input ID="keywords" name="keywords" type="text" />
    <input ID="addressee" name="addressee" type="text" />
</form>

<?php
    require_once "ImageUploaderFlashPHP/ImageUploaderFlash.class.php";
    
    $uploader = new ImageUploaderFlash("Uploader1");
    $uploader->getUploadSettings()->setActionUrl("upload.php");
    $uploader->getMetadata()->setAdditionalFormName("addForm");
    $uploader->render();
?>

Receiving Sent Data

Fields of the additional form are sent in each package, though in the following example we use package containing the first file, which number is 0, because there is always at least one file in the upload session.

PHP
<?php
    require_once "ImageUploaderFlashPHP/UploadHandler.class.php";
    function saveAllUploadedFiles($uploadedFiles) {
        $packageFields = $uploadedFiles[0]->getPackage()->getPackageFields();
        $keywords = $packageFields["keywords"];
        $addressee = $packageFields["addressee"];
    }

    $handler = new UploadHandler();
    $handler->setAllFilesUploadedCallback("saveAllUploadedFiles");
    $handler->processRequest();
?>

Using Additional Field

Additional fields can be attached to the POST request using the metadata.addCustomField(String, String, Boolean) method. It accepts the following parameters:

  1. name of the additional field
  2. value of the additional field
  3. optional parameter telling how to deal with previous value of this field, which is overwritten by default

You may add custom fields to the upload request only at runtime using the HTML5/Flash Uploader JavaScript API. Custom fields can use any format you like but should not conflict with the standard field names. See the POST Field Reference topic for a full list of standard HTML5/Flash Uploader fields.

On the server side, additional fields are accessible through the Package.PackageFields collection by their names.

The following example sends and receives an additional field named authorField. Here the metadata.addCustomField(String, String, Boolean) method is called in the BeforeUpload event handler, which fires when the upload is about to be started. For more information about events, please, see the using events section.

Sending Data

PHP
<script type="text/javascript" language="javascript">
function onBeforeUpload() {
    $au.imageUploaderFlash('Uploader1').metadata().addCustomField('authorField', 'Author Name');
}
</script>
<?php
    require_once "ImageUploaderFlashPHP/ImageUploaderFlash.class.php";
    
    $uploader = new ImageUploaderFlash("Uploader1");
    $uploader->getUploadSettings()->setActionUrl("upload.php");
    $uploader->getClientEvents()->setBeforeUpload("onBeforeUpload");
    $uploader->render();
?>

Receiving Sent Data

Additional fields are sent in each package, though in the following example we use package containing the first file, which number is 0, because there is always at least one file in the upload session.

PHP
<?php
    require_once "ImageUploaderFlashPHP/UploadHandler.class.php";
    function saveAllUploadedFiles($uploadedFiles) {
        $packageFields = $uploadedFiles[0]->getPackage()->getPackageFields();
        $author = $packageFields["authorField"];
    }

    $handler = new UploadHandler();
    $handler->setAllFilesUploadedCallback("saveAllUploadedFiles");
    $handler->processRequest();
?>

Receiving Descriptions

Each file uploaded via HTML5/Flash Uploader may have a description. There is no need to turn this possibility on, because it is enabled by default. So, let us examine how to get descriptions of uploaded files on a server using the callback function specified by the UploadHandler.FileUploadedCallback property:

PHP
<?php
    require_once "ImageUploaderFlashPHP/UploadHandler.class.php";
    function saveUploadedFile($uploadedFile) {
        $description = $uploadedFile->getDescription();
    }

    $handler = new UploadHandler();
    $handler->setFileUploadedCallback("saveUploadedFile");
    $handler->processRequest();
?>

Uploading Image-specific Data

HTML5/Flash Uploader has some imaging capabilities; let us describe two of these features, which allow uploading additional data:

  1. Rotating of images is enabled in HTML5/Flash Uploader by default. So, it is a good idea to get rotation angle on a server. To know more on how to do this, see the receiving rotation angle section.
  2. Working with EXIF and IPTC Metadata in HTML5/Flash Uploader provides, among other possibilities, an opportunity to extract and upload EXIF and IPTC fields for each user-selected image. EXIF metadata is a special information about the image, written into the file by the capturing device when an image was captured. These metadata may provide camera parameters during capturing, date and time of the capturing, photographer's name, and etc. IPTC is another metadata format, which is widely used in journalism to keep information about a photo, like byline, subject, location, and etc. See the handling EXIF and IPTC metadata section for detailed description on how to send and receive such metadata.

Receiving Rotation Angle

A rotation angle can be got through the Angle property of the UploadedFile class. HTML5/Flash Uploader measures rotation angle in degrees clockwise.

As soon as rotation of images is allowed by default, there is no need to configure HTML5/Flash Uploader to send it, so the following example shows only how to receive such data on a server.

PHP
<?php
    require_once "ImageUploaderFlashPHP/UploadHandler.class.php";
    function saveUploadedFile($uploadedFile) {
        $angle = $uploadedFile->getAngle();
    }

    $handler = new UploadHandler();
    $handler->setFileUploadedCallback("saveUploadedFile");
    $handler->processRequest();
?>

Handling EXIF and IPTC Metadata

To upload EXIF values, you should specify the desired fields using the Metadata.Exif and Metadata.Iptc properties. Both these properties represent semicolon separated lists of field names which should be extracted and uploaded along with images. Metadata.ValueSeparator sets a string separator for fields which can contain multiple string values, like IptcKeyword.

Sending Data

The following example sends two EXIF and two IPTC fields for each user-selected image:

PHP
<?php
    require_once "ImageUploaderFlashPHP/ImageUploaderFlash.class.php";
    
    $uploader = new ImageUploaderFlash("Uploader1");
    $uploader->getUploadSettings()->setActionUrl("upload.php");
    $converters = &$uploader->getConverters();
    $converter = new Converter();
    $converter->setMode("*.*=SourceFile");
    $converters[] = $converter;
    $uploader->getMetadata()->setIptc("IptcCopyrightNotice;IptcKeyword");
    $uploader->getMetadata()->setExif("ExifColorSpace;ExifDateTime");
    $uploader->getMetadata()->setValueSeparator(";");
    $uploader->render();
?>

Receiving Sent Data

The following example gets the EXIF and IPTC fields sent accordingly to the previous configuration and writes these values to the Descriptions.xml file. Here uploaded fields are contained in the Package.PackageFields collection and can be retrieved by keys named in the following way: FieldName_xx, where FieldName is a name of an EXIF or IPTC field and xx is the index of an uploaded file in this package.

PHP
<?php
    require_once "ImageUploaderFlashPHP/UploadHandler.class.php";
    function saveUploadedFile($uploadedFile) {
        $absGalleryPath = realpath("Gallery/");
        $packageFields = $uploadedFile->getPackage()->getPackageFields();
        
        $descriptions = new DOMDocument('1.0');
        if (file_exists($absGalleryPath . "/Descriptions.xml"))
            $descriptions->load($absGalleryPath . "/Descriptions.xml");
        else
            $descriptions->appendChild($descriptions->createElement("files"));
        
        $xmlFile = $descriptions->createElement("file");
        $xmlFile->setAttribute("name",  $uploadedFile->getSourceName());
        $xmlFile->setAttribute("ExifColorSpace", $packageFields["ExifColorSpace_" . $uploadedFile->getIndex()]);
        $xmlFile->setAttribute("ExifDateTime", $packageFields["ExifDateTime_" . $uploadedFile->getIndex()]);
        $descriptions->documentElement->appendChild($xmlFile);
        $descriptions->save($absGalleryPath . "/Descriptions.xml");
    }

    $handler = new UploadHandler();
    $handler->setFileUploadedCallback("saveUploadedFile");
    $handler->processRequest();
?>
Note

All date/time values have the following format: YYYY:MM:DD hh:mm:ss. For example, May 11, 2006, 2:40PM would be represented as: 2006:05:11 14:40:00.

See Also

Reference

Manual