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Azure Server-Side Binding
This demo illustrates how to configure the FileManager widget to manage files and folders in Microsoft Azure Blob Storage. To access the Azure Blob Storage, the widget uses the Remote File System Provider. This file system provider allows you to access the storage's file system on the client side. To process the HTTP requests on the server, create your own file system provider that implements the IFileSystemItemLoader, IFileSystemItemEditor, IFileUploader and IFileContentProvider interfaces.
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@model DevExtreme.MVC.Demos.Models.FileManagement.AzureStorageAccount
@if(!Model.IsEmpty()) {
@(Html.DevExtreme().FileManager()
.FileSystemProvider(provider => provider.Remote()
.Url(Url.HttpRouteUrl("FileManagementAzureApi", null)))
.Permissions(permissions => {
permissions.Download(true);
// uncomment the code below to enable file/folder management
// permissions.Create(true);
// permissions.Copy(true);
// permissions.Move(true);
// permissions.Delete(true);
// permissions.Rename(true);
// permissions.Upload(true);
})
.AllowedFileExtensions(new string[0])
.Upload(upload => upload.MaxFileSize(1048576)));
}
else {
<text>
To run the demo locally, specify your Azure storage account name, access key and container name in the web.config file.
Refer to the <a href="https://js.devexpress.com/Demos/WidgetsGallery/Demo/FileManager/AzureServerBinding/Mvc/Light/" target="_blank">
https://js.devexpress.com/Demos/WidgetsGallery/Demo/FileManager/AzureServerBinding/Mvc/Light/</a> to see the demo online.
</text>
}
using DevExtreme.MVC.Demos.Models.FileManagement;
using System.Web.Mvc;
namespace DevExtreme.MVC.Demos.Controllers {
public class FileManagerController : Controller {
public ActionResult AzureServerBinding() {
return View(AzureStorageAccount.FileManager.Value);
}
}
}
using DevExtreme.AspNet.Mvc.FileManagement;
using DevExtreme.MVC.Demos.Models.FileManagement;
using System;
using System.Net.Http;
using System.Web;
using System.Web.Http;
using System.Web.Mvc;
using System.Net.Http.Headers;
namespace DevExtreme.MVC.Demos.Controllers.ApiControllers {
public class FileManagerAzureProviderApiController : ApiController {
HttpContext CurrentContext = HttpContext.Current;
string TempDirectoryPath {
get { return CurrentContext.Server.MapPath("~/App_Data/UploadTemp"); }
}
[System.Web.Http.AcceptVerbs("GET", "POST")]
[System.Web.Http.Route("api/file-manager-azure", Name = "FileManagementAzureApi")]
public HttpResponseMessage Process() {
FileSystemCommand command;
Enum.TryParse(CurrentContext.Request["command"], out command);
string arguments = CurrentContext.Request["arguments"];
AzureStorageAccount account = AzureStorageAccount.FileManager.Value;
var provider = new AzureBlobFileProvider(account.AccountName, account.AccessKey, account.ContainerName, TempDirectoryPath);
var config = new FileSystemConfiguration {
Request = new HttpContextWrapper(CurrentContext).Request,
FileSystemProvider = provider,
//uncomment the code below to enable file/folder management
//AllowCopy = true,
//AllowCreate = true,
//AllowMove = true,
//AllowDelete = true,
//AllowRename = true,
//AllowUpload = true,
AllowDownload = true,
UploadConfiguration = new UploadConfiguration {
MaxFileSize = 1048576
},
TempDirectory = TempDirectoryPath
};
var processor = new FileSystemCommandProcessor(config);
var commandResult = processor.Execute(command, arguments);
var result = commandResult.GetClientCommandResult();
return command == FileSystemCommand.Download && commandResult.Success ? CreateDownloadResponse(result) : Request.CreateResponse(result);
}
HttpResponseMessage CreateDownloadResponse(object result) {
var fileContent = result as FileStreamResult;
if(fileContent == null)
return Request.CreateResponse(result);
var response = new HttpResponseMessage() {
Content = new StreamContent(fileContent.FileStream)
};
response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment") {
FileName = fileContent.FileDownloadName
};
response.Content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");
return response;
}
}
}
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using Microsoft.Azure.Storage;
using Microsoft.Azure.Storage.Auth;
using Microsoft.Azure.Storage.Blob;
using DevExtreme.AspNet.Mvc.FileManagement;
namespace DevExtreme.MVC.Demos.Models.FileManagement {
public class AzureBlobFileProvider : IFileSystemItemLoader, IFileSystemItemEditor, IFileUploader, IFileContentProvider {
const string EmptyDirectoryDummyBlobName = "aspxAzureEmptyFolderBlob";
const string TempFilePrefix = "azuredownload_";
public AzureBlobFileProvider(string storageAccountName, string storageAccessKey, string containerName, string tempDirPath) {
StorageAccountName = storageAccountName;
StorageAccessKey = storageAccessKey;
ContainerName = containerName;
TempDirectoryPath = tempDirPath;
}
string StorageAccountName { get; set; }
string StorageAccessKey { get; set; }
string ContainerName { get; set; }
string TempDirectoryPath { get; set; }
CloudBlobContainer _container;
CloudBlobContainer Container {
get {
if(this._container == null) {
var credentials = new StorageCredentials(StorageAccountName, StorageAccessKey);
var account = new CloudStorageAccount(credentials, true);
var client = account.CreateCloudBlobClient();
this._container = client.GetContainerReference(ContainerName);
}
return this._container;
}
}
public IEnumerable<FileSystemItem> GetItems(FileSystemLoadItemOptions options) {
var result = new List<FileSystemItem>();
BlobContinuationToken continuationToken = null;
string dirKey = GetFileItemPath(options.Directory);
if(!string.IsNullOrEmpty(dirKey))
dirKey = dirKey + "/";
CloudBlobDirectory dir = Container.GetDirectoryReference(dirKey);
do {
BlobResultSegment segmentResult = dir.ListBlobsSegmented(continuationToken);
continuationToken = segmentResult.ContinuationToken;
foreach(IListBlobItem blob in segmentResult.Results) {
var item = new FileSystemItem();
string name = GetFileItemName(blob);
if(name == EmptyDirectoryDummyBlobName)
continue;
if(blob is CloudBlob) {
var blockBlob = (CloudBlob)blob;
item.Name = name;
item.DateModified = blockBlob.Properties.LastModified.GetValueOrDefault().DateTime;
item.Size = blockBlob.Properties.Length;
} else if(blob is CloudBlobDirectory) {
var subDir = (CloudBlobDirectory)blob;
item.Name = name.Substring(0, name.Length - 1);
item.IsDirectory = true;
item.HasSubDirectories = GetHasDirectories(subDir);
item.DateModified = DateTime.UtcNow;
} else {
throw new Exception("Unsupported blob type");
}
result.Add(item);
}
} while(continuationToken != null);
return result.OrderByDescending(item => item.IsDirectory)
.ThenBy(item => item.Name)
.ToList();
}
bool GetHasDirectories(CloudBlobDirectory dir) {
bool result;
BlobContinuationToken continuationToken = null;
do {
BlobResultSegment segmentResult = dir.ListBlobsSegmented(continuationToken);
continuationToken = segmentResult.ContinuationToken;
result = segmentResult.Results.Any(blob => blob is CloudBlobDirectory);
} while(!result && continuationToken != null);
return result;
}
public void CreateDirectory(FileSystemCreateDirectoryOptions options) {
string path = GetFileItemPath(options.ParentDirectory);
string blobKey = $"{options.DirectoryName}/{EmptyDirectoryDummyBlobName}";
if(!string.IsNullOrEmpty(path))
blobKey = $"{path}/{blobKey}";
CloudBlockBlob dirBlob = Container.GetBlockBlobReference(blobKey);
dirBlob.UploadText("");
}
public void RenameItem(FileSystemRenameItemOptions options) {
string newName = options.ItemNewName;
string key = GetFileItemPath(options.Item);
int index = key.LastIndexOf('/');
string newKey;
if(index >= 0) {
string parentKey = key.Substring(0, index + 1);
newKey = parentKey + newName;
} else
newKey = newName;
Copy(key, newKey, true);
}
public void MoveItem(FileSystemMoveItemOptions options) {
Copy(options.Item, options.DestinationDirectory, true);
}
public void CopyItem(FileSystemCopyItemOptions options) {
Copy(options.Item, options.DestinationDirectory, false);
}
void Copy(FileSystemItemInfo sourceItem, FileSystemItemInfo destinationItem, bool deleteSource = false) {
string sourceKey = GetFileItemPath(sourceItem);
string destinationKey = GetFileItemPath(destinationItem) + "/" + sourceItem.Name;
Copy(sourceKey, destinationKey, deleteSource);
}
void Copy(string sourceKey, string destinationKey, bool deleteSource) {
CloudBlob blob = Container.GetBlobReference(sourceKey);
bool isFile = blob.Exists();
if(isFile)
CopyFile(blob, destinationKey, deleteSource);
else
CopyDirectory(sourceKey, destinationKey + "/", deleteSource);
}
public void DeleteItem(FileSystemDeleteItemOptions options) {
string key = GetFileItemPath(options.Item);
CloudBlob blob = Container.GetBlobReference(key);
bool isFile = blob.Exists();
if(isFile)
RemoveFile(blob);
else
RemoveDirectory(key + "/");
}
public void UploadFile(FileSystemUploadFileOptions options) {
string destinationKey = $"{options.DestinationDirectory.Path}/{options.FileName}";
CloudBlockBlob newBlob = Container.GetBlockBlobReference(destinationKey);
newBlob.UploadFromFile(options.TempFile.FullName);
}
void RemoveFile(CloudBlob blob) {
blob.Delete();
}
void RemoveDirectory(string key) {
CloudBlobDirectory dir = Container.GetDirectoryReference(key);
RemoveDirectory(dir);
}
void RemoveDirectory(CloudBlobDirectory dir) {
var children = new List<IListBlobItem>();
BlobContinuationToken continuationToken = null;
do {
BlobResultSegment segmentResult = dir.ListBlobsSegmented(continuationToken);
continuationToken = segmentResult.ContinuationToken;
children.AddRange(segmentResult.Results);
} while(continuationToken != null);
foreach(IListBlobItem blob in children) {
if(blob is CloudBlob) {
RemoveFile((CloudBlob)blob);
} else if(blob is CloudBlobDirectory) {
RemoveDirectory((CloudBlobDirectory)blob);
} else {
throw new Exception("Unsupported blob type");
}
}
}
void CopyFile(CloudBlob blob, string destinationKey, bool deleteSource = false) {
CloudBlob blobCopy = Container.GetBlobReference(destinationKey);
blobCopy.StartCopy(blob.Uri);
if(deleteSource)
blob.Delete();
}
void CopyDirectory(string sourceKey, string destinationKey, bool deleteSource = false) {
CloudBlobDirectory dir = Container.GetDirectoryReference(sourceKey);
CopyDirectory(dir, destinationKey, deleteSource);
}
void CopyDirectory(CloudBlobDirectory dir, string destinationKey, bool deleteSource = false) {
var children = new List<IListBlobItem>();
BlobContinuationToken continuationToken = null;
do {
BlobResultSegment segmentResult = dir.ListBlobsSegmented(continuationToken);
continuationToken = segmentResult.ContinuationToken;
children.AddRange(segmentResult.Results);
} while(continuationToken != null);
foreach(IListBlobItem blob in children) {
string childCopyName = GetFileItemName(blob);
string childCopyKey = $"{destinationKey}{childCopyName}";
if(blob is CloudBlob) {
CopyFile((CloudBlob)blob, childCopyKey, deleteSource);
} else if(blob is CloudBlobDirectory) {
CopyDirectory((CloudBlobDirectory)blob, childCopyKey, deleteSource);
} else {
throw new Exception("Unsupported blob type");
}
}
}
string GetFileItemName(IListBlobItem blob) {
string escapedName = blob.Uri.Segments.Last();
return Uri.UnescapeDataString(escapedName);
}
string GetFileItemPath(FileSystemItemInfo item) {
return item.Path.Replace('\\', '/');
}
public void RemoveUploadedFile(FileInfo file) {
file.Delete();
}
public Stream GetFileContent(FileSystemLoadFileContentOptions options) {
if(!Directory.Exists(TempDirectoryPath))
Directory.CreateDirectory(TempDirectoryPath);
CleanUpDownloadedFiles();
string tempFileName = string.Format("{0}{1}.tmp", TempFilePrefix, Guid.NewGuid().ToString("N"));
string tempFilePath = Path.Combine(TempDirectoryPath, tempFileName);
string key = GetFileItemPath(options.File);
CloudBlockBlob blob = Container.GetBlockBlobReference(key);
blob.DownloadToFile(tempFilePath, FileMode.Create);
return File.Open(tempFilePath, FileMode.Open, FileAccess.Read, FileShare.Read);
}
void CleanUpDownloadedFiles() {
var timeout = TimeSpan.FromMinutes(10);
try {
var dir = new DirectoryInfo(TempDirectoryPath);
var files = dir.GetFiles(TempFilePrefix + "*.tmp")
.Where(file => DateTime.UtcNow - file.LastWriteTimeUtc > timeout);
foreach(FileInfo file in files) {
try {
file.Delete();
} catch { }
}
} catch { }
}
}
}