IContentAsyncWriteAsync Method

IT Hit WebDAV Classes Reference

Saves the content of the file from the specified stream to the WebDAV repository.

Namespace: ITHit.WebDAV.Server
Assembly: ITHit.Server (in ITHit.Server.dll) Version: 9.1.5311-Beta

Syntax

Task<bool> WriteAsync(
	Stream content,
	string contentType,
	long startIndex,
	long totalFileSize
)

Function WriteAsync ( 
	content As Stream,
	contentType As String,
	startIndex As Long,
	totalFileSize As Long
) As Task(Of Boolean)

Task<bool>^ WriteAsync(
	Stream^ content, 
	String^ contentType, 
	long long startIndex, 
	long long totalFileSize
)

abstract WriteAsync : 
        content : Stream * 
        contentType : string * 
        startIndex : int64 * 
        totalFileSize : int64 -> Task<bool>

Parameters

content: Type: System.IOStream
Stream to read the content of the file from.
contentType: Type: SystemString
Indicates the media type of the file.
startIndex: Type: SystemInt64
Start offset to which content shall be saved.
totalFileSize: Type: SystemInt64
Entire length of the file. Is is not less then length of content stream.

Return Value

Type: TaskBoolean
Boolean value indicating whether entire stream was written. This value is used by the engine to take decision whether autocheckin shall be performed.

Exceptions

Exception	Condition
[!:LockedException]	The file was locked and client did not provide lock token.
[!:NeedPrivilegesException]	The user doesn't have enough privileges.
[!:InsufficientStorageException]	Quota limit is reached.
[!:DavException]	In other cases.

Remarks

IIS and ASP.NET does not support files upload larger than 2Gb. If you need to upload files larger than 2Gb you must develop HttpListener-based WebDAV server or implement resumable upload interfaces.

If you are creating HttpHandler-based WebDAV server you must specify the file maximum upload size in web.config of your web application. By default maximum upload size is set to 4096 KB (4 MB) by ASP.NET. This limit is used to prevent denial of service attacks caused by users posting large files to the server. To increase the upload limit add <httpRuntime> section to your web application web.config file and specify the limit in kilobytes:

XML

Copy

<configuration>
   <system.web>
      ...
      <httpRuntime maxRequestLength="2097151" /> //2Gb
      ...
   </system.web>
</configuration>

When client uploads file to IIS, ASP.NET first creates the file in a the temporary upload directory. Only when the entire file is uploaded to server you can read its content from stream. By default ASP.NET uploads files to %FrameworkInstallLocation%\Temporary ASP.NET Files folder. You must make sure you have enough disk space to keep temporary files uploaded to your server. To change this folder location add the following section to your web.config file:

XML

Copy

<configuration>
    <system.web>
       ...
       <compilation tempDirectory="temporary files directory" />
       ...
    </system.web>
</configuration>

To avoid temporary file creation and pass content directly to engine set the ResumableUpload.PutUploadProgressAndResumeModule module in your web.config file. Unlike IIS/ASP.NET, HttpListener-based server does not create any temporary files when handling uploads.

Examples

The code below is part of 'WebDAVServer.FileSystemStorage.AspNet' C# & VB samples provided with the SDK.

C++

Copy

public virtual async Task<bool> WriteAsync(Stream content, string contentType, long startIndex, long totalFileSize)
{
    await RequireHasTokenAsync();
    //Set timeout to maximum value to be able to upload large files.
    HttpContext.Current.Server.ScriptTimeout = int.MaxValue;
    if (startIndex == 0 && fileInfo.Length > 0)
    {
        using (FileStream filestream = fileInfo.Open(FileMode.Truncate)) { }
    }
    await fileInfo.SetExtendedAttributeAsync("TotalContentLength", (object)totalFileSize);
    await fileInfo.SetExtendedAttributeAsync("SerialNumber", ++this.serialNumber);

    using (FileStream fileStream = fileInfo.Open(FileMode.OpenOrCreate, FileAccess.Write, FileShare.Read))
    {
        if (fileStream.Length < startIndex)
        {
            throw new DavException("Previous piece of file was not uploaded.", DavStatus.PRECONDITION_FAILED);
        }

        if (!content.CanRead)
        {
            return true;
        }

        fileStream.Seek(startIndex, SeekOrigin.Begin);
        byte[] buffer = new byte[bufSize];

        int lastBytesRead;
        try
        {
            lastBytesRead = await content.ReadAsync(buffer, 0, bufSize);
            while (lastBytesRead > 0)
            {
                await fileStream.WriteAsync(buffer, 0, lastBytesRead);
                await fileStream.FlushAsync();
                lastBytesRead = await content.ReadAsync(buffer, 0, bufSize);
            }
        }
        catch (HttpException)
        {
            // The remote host closed the connection (for example Cancel or Pause pressed).
        }
    }
    await context.socketService.NotifyRefreshAsync(GetParentPath(Path));
    return true;
}

Public Overridable Async Function WriteAsync(content As Stream, contentType As String, startIndex As Long, totalFileSize As Long) As Task(Of Boolean) Implements IContentAsync.WriteAsync
    Await RequireHasTokenAsync()
    'Set timeout to maximum value to be able to upload large files.
    HttpContext.Current.Server.ScriptTimeout = Integer.MaxValue
    If startIndex = 0 AndAlso fileInfo.Length > 0 Then
        Using filestream As FileStream = fileInfo.Open(FileMode.Truncate)
             End Using
    End If

    Await fileInfo.SetExtendedAttributeAsync("TotalContentLength", CObj(totalFileSize))
    Await fileInfo.SetExtendedAttributeAsync("SerialNumber", System.Threading.Interlocked.Increment(Me.serialNumber))
    Using fileStream As FileStream = fileInfo.Open(FileMode.OpenOrCreate, FileAccess.Write, FileShare.Read)
        If fileStream.Length < startIndex Then
            Throw New DavException("Previous piece of file was not uploaded.", DavStatus.PRECONDITION_FAILED)
        End If

        If Not content.CanRead Then
            Return True
        End If

        fileStream.Seek(startIndex, SeekOrigin.Begin)
        Dim buffer As Byte() = New Byte(1048575) {}
        Dim lastBytesRead As Integer
        Try
            lastBytesRead = Await content.ReadAsync(buffer, 0, bufSize)
            While lastBytesRead > 0
                Await fileStream.WriteAsync(buffer, 0, lastBytesRead)
                Await fileStream.FlushAsync()
                lastBytesRead = Await content.ReadAsync(buffer, 0, bufSize)
            End While
        Catch __unusedHttpException1__ As HttpException
            ' The remote host closed the connection (for example Cancel or Pause pressed).
             End Try
    End Using

    Await context.socketService.NotifyRefreshAsync(GetParentPath(Path))
    Return True
End Function

Reference

IContentAsync Interface

ITHit.WebDAV.Server Namespace

IContentAsyncAddLanguageSpecificTextSet("LSTD5A6D716_0?cpp=::|nu=.");WriteAsync Method

Parameters

Return Value

Reference

IContentAsyncWriteAsync Method