Data Sharing Between Apps

Shared Contexts

.NET

Updating a Context

See our .NET Shared Contexts example on GitHub.

First, make sure you initialize the Glue object with Contexts enabled:

  Glue.Initialize(
    applicationName: "ApplicationThatUsesContexts",
    useContexts: true // true by default
    );

At this point, you can proceed to creating and retrieving Contexts, update them and respond to changes:

  // if "TestContext" doesn't exist, it will be automatically created
  IContext context = await Glue.Contexts.GetContext("TestContext");

You can update some of the properties of the object, while the others remain the same:

context["Contact"] = new { AccountName = "ACC001", Name = "John Smith" };  
context["Test"] = new Dictionary<string, List<object>> { { "Key", new List<object> { 1, 2, 3 } } };

To remove a property, set it to null:

context["Alpha"] = null;

A transactional update:

await context.Update(ctx => { ctx["Foo"] = "Bar"; ctx["now"] = DateTime.Now; });

Or, in a more strongly typed manner:

// define user-specific context with its own properties
public class Status
{
    public string State {get;set;}
    public DateTime Date {get;set;}
    // etc.
}

public interface IMyContextType : IContext
{
    Status MyProperty {get;set;}
    int SomeOtherProperty {get;set;}
    // you can add more POCO's here to reflect your application needs
}

IMyContextType myContext = await Glue.Contexts.GetContext<IMyContextType>("TestContext"); 
// myContext is proxy-code generated by Glue42 so when reading/writing from/to the IMyContextType
// you effectively read/write from/to the Glue42 context

myContext.MyProperty = GetCurrentStatus();

Contexts are keyed by name, so every .NET, JavaScript or other Glue42 enabled application that requests TestContext will have access to the same data.

Replacing a Context

In addition to updating the context, you can also replace the entire context object by using the Set() method of the context object:

// setting value of the context replaces the entire context object
await context.Set(new { Alpha = "A", Beta = "B" });

// you can use Dictionaries as well
await context.Set(new Dictionary<string, object> { { "Alpha", "A" }, { "Beta", "B" } });

Subscribing for Context Updates

An example of responding to context data update events:

context.ContextUpdated += Context__ContextUpdated;

void Context__ContextUpdated(object sender, ContextUpdatedEventArgs e)
{
    Console.WriteLine("Context updated: " + new
    {
        (sender as IContext).ContextId,
        (sender as IContext).ContextName,
        e.IsReset,
        Added = "[" + string.Join(", ", e.Added.Select(x => x + "")) + "]",
        Updated = "[" + string.Join(", ", e.Updated.Select(x => x + "")) + "]",
        Removed = "[" + string.Join(", ", e.Removed.Select(x => x + "")) + "]",
    });
}

An example of responding to context creation/deletion events:

Glue.Contexts.Created += Contexts_Created;
void Contexts_Created(object sender, ContextStateEventArgs e)
{
    Console.WriteLine("Context created: " + new { e.ContextId, e.ContextName });
}

Glue.Contexts.Removed += Contexts_Removed;
void Contexts_Removed(object sender, ContextStateEventArgs e)
{
    Console.WriteLine("Context removed: " + new { e.ContextId, e.ContextName });
}

Unsubscribing

To unsubscribe from context updates:

context.ContextUpdated -= Context__ContextUpdated;
Glue.Contexts.Created -= Contexts_Created;
Glue.Contexts.Removed -= Contexts_Removed;

Listing All Available Contexts

To get the names of all currently available shared contexts, use:

string[] contextNames = Glue.Contexts.GetContexts();