WebSync: Tutorials

On-Demand:

Basic

Server: Advanced

In this tutorial you will learn how to persist message data after it is published on the server.

Prerequisites

You have completed the WebSync Server: Basic tutorial.

Configuring your project

Before you can start coding, you need to have the correct project references.

Add a reference to FM.WebSync.Core (available as part of the WebSync Server downloads).
Add a reference to FM.WebSync.Server (available as part of the WebSync Server downloads).
Add a reference to System.Runtime.Serialization (available as part of the .NET Framework).

Persisting messages in a handler method

A slightly more complicated example is persisting data incoming from client publications.

Modify the request handler created in the WebSync Server: Basic tutorial.
1. Define a Data class for the purpose of deserialization.
2. Add a method called PostPublish.
3. In this method, iterate over the messages and persist the data.text property.

using System;
using System.IO;
using System.Runtime.Serialization;
using FM.WebSync.Server;
using FM.WebSync.Core;

namespace Tutorials
{
    [HandlerProvider(ProviderType.Basic)]
    public class RequestHandler : Handler<RequestHandler>
    {
        [DataContract]
        private class Data
        {
            [DataMember(Name = "text")]
            public string Text { get; set; }
        }

        [HandlerEvent(HandlerEventType.AfterPublish, HandlerEventContinue.Immediate)]
        public static void PostPublish(object sender, HandlerEventArgs e)
        {
            foreach (Message message in e.Messages)
            {
                Data data = JSON.Deserialize<Data>(message.Data);
                
                // write to file
                try
                {
                    string directory = @"C:\WebSync\";
                    string file = "log.txt";
                    string path = directory + file;

                    if (!Directory.Exists(directory))
                        Directory.CreateDirectory(directory);

                    if (!File.Exists(path))
                        File.WriteAllText(path, data.Text + Environment.NewLine);
                    else
                        File.AppendAllText(path, data.Text + Environment.NewLine);
                }
                catch (Exception)
                {
                    // whoops! check your file system permissions
                    continue;
                }
            }
        }
    }
}

Testing

Open up your client page in a couple windows and check C:\WebSync\log.txt for a log of all published messages!