Lutece blobstore plugin

Plugin's description

Introduction

This plugin handles the big data storage, in database or file system.

Configuration

Configure the private key for the signature in the file blobstore_context.xml :

<bean id="blobstore.hashService" class="fr.paris.lutece.util.signrequest.security.Sha1HashService" />
<bean id="blobstore.requestAuthenticator" class="fr.paris.lutece.util.signrequest.RequestHashAuthenticator" >
	<property name="hashService" ref="blobstore.hashService" />
	<property name="signatureElements" > 
		<list>
			<value>blobstore</value>
			<value>blob_key</value>
		</list>
	</property>
	<property name="privateKey">
		<value>change me</value>
	</property>
</bean>

Usage

There are two ways of using the plugin-blobstore.

- A: Use as a FileService via the blobStoreFileServiceProvider (recommanded)

- B: Use in addition of a plugin in which the latter will be able to store big data in a distinct database or in file system.

Each data is linked to an ID blob which is generated randomly. The use of the library java.util.UUID ensures the unicity of the ids.

A/ Use the blobStoreFileServiceProvider

The fileStoreService can be added to the Home class :

private static IFileStoreServiceProvider _fileStoreService = FileService.getInstance( ).getFileStoreServiceProvider( "blobStoreProvider");

You can then use that fileStoreService :

...
	// get the file in multipart request and store it
        IFileStoreServiceProvider fileStoreService = MyHome.getFileStoreServiceProvider( );
        FileItem file = multipartRequest.getFile( "file" );
      
        if ( file != null  	&& file.getSize( ) > 0 )
        {
            try
            {
                String strFileStoreKey = fileStoreService.storeFileItem( file );
...
	// get an URL for display
	String strFileUrl = fileStoreService.getFileDownloadUrlBO( strFileKey );
...

B/ Step 1 : Implentation of a service that will use a BlobStoreService"

First of all, create a new service that has a private attribute type BlobStoreService :

public class MyPluginService
{
    private BlobStoreService _blobStoreService;

    /**
     * Set the BlobStoreService
     * @param blobStoreService the {@link BlobStoreService}
     */
    public void setBlobStoreService( BlobStoreService blobStoreService )
    {
        _blobStoreService = blobStoreService;
    }
    .
    .
    .
}

Next, define the service in the XML file of the plugin (ex : webapp/WEB-INF/plugins/myplugin_context.xml). It is in this file where the stored data type is defined.

To store in database (modify the bold words) :

<bean id="myplugin.blobStoreService" class="fr.paris.lutece.plugins.blobstore.service.database.DatabaseBlobStoreService">
	<property name="name" value="myplugin.blobStoreService" />
</bean>
<bean id="myplugin.myPluginService" class="fr.paris.lutece.plugins.myplugin.service.MyPluginService">
	<property name="blobStoreService" ref="myplugin.blobStoreService" />
</bean>

To store in file system (modify the bold words) :

<bean id="myplugin.blobStoreService" class="fr.paris.lutece.plugins.blobstore.service.filesystem.FileSystemBlobStoreService">
	<property name="name" value="<strong>myplugin</strong>.blobStoreService" />
	<property name="basePath" value="D:\data\blobstore" />
	<property name="depth" value="1" />
</bean>
<bean id="myplugin.myPluginService" class="fr.paris.lutece.plugins.myplugin.service.MyPluginService">
	<property name="blobStoreService" ref="myplugin.blobStoreService" />
</bean>

B/ Step 2 : Implementation of basic methods of the BlobStoreService

The API of BlobStoreService offers several functionnalities that allows to implements basic operation?

To store a blob with an array of bytes or with an InputStream :

public void storeBlob( byte[] blob )
{
	// Plugin operation
	...
	_blobStoreService.store( blob );
	...
}

public void storeBlob( InputStream blob )
{
	// Plugin operation
	...
	_blobStoreService.storeInputStream( blob );
	...
}

To modify a blob with an array of bytes or with an InputStream :

public void updateBlob( String strKey, byte[] blob )
{
	// Plugin operation
	...
	_blobStoreService.update( strKey, blob );
	...
}

public void updateBlob( String strKey, InputStream blob )
{
	// Plugin operation
	...
	_blobStoreService.updateInputStream( strKey, blob );
	...
}

To delete a blob :

public void deleteBlob( String strKey )
{
	// Plugin operation
	...
	_blobStoreService.delete( strKey );
	...
}

It is also possible to retrieve the URL to download the stored file :

public String getBlobUrl( String strKey )
{
	// Plugin operation
	...
	String strBlobUrl = _blobStoreService.getBlobUrl( strKey );
	...
}

public String getFileUrl( String strKey )
{
	// Plugin operation
	...
	String strFileUrl = _blobStoreService.getFileUrl( strKey );
	...
}