Use PHP and MongoDB GridFS to handle images and videos. Fewer files in your file system, plus the utility of cloud services.
Recently, I’ve been working with MongoDB and GridFS in PHP to upload images and videos and stream them back out on the fly. Using the GridFS lets us bypass our own filesystem so we wouldn’t have to take up space on our own servers. While it may seem moot when you upload a few images, the point is really driven home if you have a media library of many large sized videos.
For those who are not familiar with MongoDB, it is an open-source NoSQL database,
and GridFS is a built-in feature used to store large files into MongoDB. Now that I’m more comfortable with Mongo and the PHP driver, it is a great way to store and stream media. Here’s how:
Storing images and videos into the GridFS
First, you’ll need a connection to the GridFS for your MongoDB. Let’s call this file saveFile.php;
<?php
// connect to the ‘myGrid’ GridFS
$m = new Mongo(); // gets a connection to Mongo
$db = $m->myDB; // gets connection to database called "myDB";
$myGrid = $db->getGridFS('myGrid'); // gets a GridFS;
?>
To store a file into the GridFS, you need to call the storeFile method.
<?php // store a file into the GridFS $myGrid->storeFile($some_file, $data_array); ?>
You might want to store some information along with your file, such as timestamp, mime type, etc. so your data array can look like this:
<?php
// some extra data you may want to store with your file
$data_array = array(
'mime' => mime_content_type($some_file),
'timestamp' => time(),
'metadata' => array( $more_meta_data ),
);
?>
When you store a file into the GridFS, it creates two collections: myGrid.chunks and myGrid.files. myGrid.files contains the metadata for your file, while myGrid.chunks contains the chunked media data.
Fetching files from the GridFS
In order to get a handle to the file that you stored, you will need to query your GridFS.
So in another file, called displayFile.php
<?php
// connect to the ‘myGrid’ GridFS
$m = new Mongo();
$myGrid = $m->myDB->getGridFS('myGrid');
$query = array( $some_query_criteria);
$myGrid->find($query);
?>
Your $query variable will be the criteria to which you want to filter through your files.
Generally, if no checking is done, then the MongoID will be the only unique key, so let’s pull a file out using a known MongoID.
<?php // get a reference to your GridFSFile $query = array( '_id' = new MongoID($known_mongoID), ); $grid_files = $myGrid->find($query); ?>
The query will return an array of objects so you have to iterate through them to get its data.
These objects are just database file objects and not the actual media content.
So: let’s display the media directly from the gridFSFile.
Stream the content of your GridFSFile
Get a reference to your GridFSFile and call the getBytes() method to stream the chunks into your browser. So in the same displayFile.php file:
<?php
foreach($grid_files as $grid_file){
// access your myGrid.files collection data
$file_meta = $grid_file->file;
// set the header type of what the file is; this is where
// the 'mime' => mime_content_type($some_file)
// from before comes into play
header('Content-type: '. $file_meta[‘mime’] );
// if the file is a video, then the Content-Length header
// must also be set; images don’t need it
header('Content-Length:'.$file_meta[‘length’] );
echo $grid_file->getBytes();
}
?>
Now if you visit the page displayFile.php you will be able to see your image or video streamed directly from your GridFS. No need to use your own file system!
The entire code:
<?php
/* * * saveFile.php */
// connect to the ‘myGrid’ GridFS
$m = new Mongo();
$db = $m->myDB;
$myGrid = $db->getGridFS('myGrid');
// some extra data you may want to store with your file
$data_array = array(
'mime' => mime_content_type($some_file),
'timestamp' => time(),
'metadata' => array( $more_meta_data ),
);
// store a file into the GridFS
$myGrid->storeFile($some_file, $data_array);
?>
<?php
/* * * displayFile.php */
// connect to the ‘myGrid’ GridFS
$m = new Mongo();
$myGrid = $m->myDB->getGridFS('myGrid');
$query = array(
'_id' = new MongoID($known_mongoID_as_string),
);
$grid_files = $myGrid->find($query);
foreach($grid_files as $grid_file){
// access your myGrid.files collection data
$file_meta = $grid_file->file;
header('Content-type: '. $file_meta['mime'] );
/* not needed if image */
header('Content-Length:'.$file_meta[‘length’] );
echo $grid_file->getBytes();
}
?>
To get further utility from this, you can set the source of your image or video to this url and it will display accordingly in your webpage:
<!-- if your file is an image -->
<img src = “displayFile.php”/>
<!-- or if your file is a video you can use the html5
video tag to stream it -->
<video width="320" height="240" controls="controls">
<source src="displayFile.php"
type="<?php echo $file_meta['mime'];?>" />
Your browser does not support the video tag.
</video>
<!-- * Note: the video example assumes you have a reference to
the mime type of your file -->
And there you have it: save files to MongoDB and stream them onto your webpage. You can get more information at: http://www.mongodb.org/ and find the PHP driver API here: http://php.net/manual/en/mongo.gridfs.php
