Add /Update Cache Data with Streams

The GetCacheStream method is used for adding and updating the data within a stream. If the key provided with GetCacheStream API does not exist in the cache, the data written on the stream is added to the cache.

If an item already exists in the cache with the provided key, binary data written on the stream is appended with the existing data against the specified key.

Pre-Requisites

• .NET/.NET Core
• Java

• Include the following namespaces in your application:
  • Alachisoft.NCache.Runtime.Caching
  • Alachisoft.NCache.Client
  • Alachisoft.NCache.Runtime.Exceptions
• Cache must be running.
• Make sure that the data being added is serializable.
• To ensure the operation is fail safe, it is recommended to handle any potential exceptions within your application, as explained in Handling Failures.

• .NET/.NET Core
• Java

try
{
    // Pre-condition: Cache is already connected
    // Generate a unique cache key
    string key = "StreamKey";

    // Initialize CacheStream object
    CacheStream cacheStream = null;

    // Set StreamMode object to Read mode
    StreamMode streamMode = StreamMode.Write;

    // Provide the streamMode object to cachestreamAttributes object 
    var streamAttributes = new CacheStreamAttributes(streamMode);

    // ReadAllBytes returns the stream from the provided path in a byte Array
    byte[] dataToWrite = System.IO.File.ReadAllBytes("C:\\ncache-manual.pdf");

    // Use GetCacheStream to set streamAttributes against the specified key 
    cacheStream = cache.GetCacheStream(key, streamAttributes);

    // Write data in buffer
    cacheStream.Write(dataToWrite, 0, dataToWrite.Length);

    //...Close stream
}
catch (OperationFailedException ex)
{
    // Exception can occur due to:
    // Connection Failures
    // Operation Timeout
    // Operation performed during state transfer
}
catch (Exception ex)
{
    // handle exception
    // This includes StreamException
}

Additional Resources

NCache provides sample application for streaming at:

• GitHub
• Shipped with NCache: %NCHOME%\samples\dotnet\Streaming

See Also

Continuous Query
Read/Write Streams
Retrieving Data from Streams
Closing a Stream
Security and Encryption