LightDMS is a light document version system implementation plugin for Rhetos development platform. It automatically creates DocumentVersion and other entities for managing documents (and their version) in Rhetos based solutions. Aside entities, versioning, it also exposes additional web interface for uploading/downloading files.

See rhetos.org for more information on Rhetos.

LightDMS plugin provides the following web API methods. Check out your Rhetos server homepage (http://localhost/Rhetos) for sample code and demonstration of the LightDMS web API.

Upload:

• Uploading a file: <RhetosSite>/LightDMS/Upload
  • Example format http://localhost/Rhetos/LightDMS/Upload/8EF65043-2E2A-424D-B76F-4DAA5A48CB3D
  • Response contains file content ID. Note that one LightDMS document may be related to many files, one for each version of the document.

Download:

• Downloading a file with given file content ID: <RhetosSite>/LightDMS/DownloadPreview/{{ID}}?filename={{filename}}

  • The ID parameter is GUID formatted file content ID.
  • The filename query parameter is a name that the browser will offer to the user when saving the downloaded file.
  • Example format http://localhost/Rhetos/LightDMS/DownloadPreview/8EF65043-2E2A-424D-B76F-4DAA5A48CB3D?filename=somefile.txt
  • Parametrized format http://localhost/Rhetos/LightDMS/DownloadPreview?id=8EF65043-2E2A-424D-B76F-4DAA5A48CB3D&filename=somefile.txt (since 1.8.0)

• Downloading a file with given document version ID: <RhetosSite>/LightDMS/Download/{{ID}}

  • The ID parameter is GUID formatted document version ID.
  • Example format http://localhost/Rhetos/LightDMS/Download/8EF65043-2E2A-424D-B76F-4DAA5A48CB3D
  • Parametrized format http://localhost/Rhetos/LightDMS/Download?id=8EF65043-2E2A-424D-B76F-4DAA5A48CB3D (since 1.8.0)

LightDMS allows the following storage options:

1. Simple BLOB storage in the database table
2. Database FILESTREAM storage
   • This is a large performance improvement over the simple BLOB storage.
   • The files are accessed through the database API but are physically stored as file on a server disk.
3. Azure Blob Storage (currently download-only)
   • This option currently works as an extension of the FILESTREAM storage. The files are uploaded to FILESTREAM. A custom scheduled process is expected to migrate the files to Azure Blob Storage (archive). LightDMS will then download the archived file from Azure.

1. Enable FileStream on SqlServer instance - Sql Server Configuration Manager Steps

2. Enable FileStream on database level:

   EXEC sp_configure filestream_access_level, 2
   RECONFIGURE;

3. Setup FileGroup on database level to enable FileStream option for varbinary(max) column:

   ALTER DATABASE <DB_Name>
   ADD FILEGROUP fs_Group CONTAINS FILESTREAM;
   GO
   -- Minimum one location where to save files for that fileGroup
   ALTER DATABASE <DB_Name>
   ADD FILE ( NAME = 'fs_<DB_Name>', FILENAME = '<LOCAL_DIR_PATH>' )
   TO FILEGROUP fs_Group;

4. Test that FileStream is enabled and can be used for varbinary(max) COLUMN

   CREATE TABLE dbo.Test_FS
   (
       ID uniqueidentifier PRIMARY KEY ROWGUIDCOL,
       Content varbinary(max) FILESTREAM
   );
   DROP TABLE dbo.Test_FS;

Option A: If you have enabled FILESTREAM on your database, it will automatically be used by LightDMS after the next execution of DeployPackages.exe.

Option B: If you have already executed DeployPackages.exe to deploy LightDMS package before enabling FILESTREAM on the database, and you do not want to execute DeployPackages.exe again, the FILESTREAM usage in LightDMS can be activated by running the following SQL script on the database:

DECLARE @Error INT = 0;
BEGIN TRAN;

ALTER TABLE LightDMS.FileContent ALTER COLUMN ID ADD ROWGUIDCOL;
IF @@ERROR > 0 RETURN;

EXEC @Error = sp_rename 'LightDMS.FileContent.Content', 'Content_backup' , 'COLUMN';
IF @Error > 0 OR @@ERROR > 0 RETURN;

EXEC @Error = sp_executesql N'ALTER TABLE LightDMS.FileContent ADD Content varbinary(max) FILESTREAM';
IF @Error > 0 OR @@ERROR > 0 RETURN;

EXEC @Error = sp_executesql N'UPDATE LightDMS.FileContent SET Content = Content_backup';
IF @Error > 0 OR @@ERROR > 0 RETURN;

EXEC @Error = sp_executesql N'ALTER TABLE LightDMS.FileContent DROP COLUMN Content_backup';
IF @Error > 0 OR @@ERROR > 0 RETURN;

COMMIT;
GO
IF @@TRANCOUNT > 0 ROLLBACK;

Note: This package is already available at the NuGet.org online gallery. You don't need to build it from source in order to use it in your application.

To build the package from source, run Build.bat. The script will pause in case of an error. The build output is a NuGet package in the "Install" subfolder.

To install this package to a Rhetos server, add it to the Rhetos server's RhetosPackages.config file and make sure the NuGet package location is listed in the RhetosPackageSources.config file.

• The package ID is "Rhetos.LightDMS". This package is available at the NuGet.org online gallery. It can be downloaded or installed directly from there.
• For more information, see Installing plugin packages.