User Specific Response

[Alessandro]

Vishnu,

Thanks for using Lightstreamer.

The easiest way to achieve your required behavior is that each user subscribes to a unique itemname (perhaps bound to his username). Then, when another user posts a message for him, the Data Adapter will publish such message as an update to that specific itemname. You can deliver the messages to your Data Adapter in a couple of ways:
- by using the sendMessage function (that delivers the message to the Metadata Adapter, that in turns can send it to the Data Adapter)
- by sending the message to an external server-side component (e.g. PHP page, servlet, etc.) that in turns sends the message to the Data Adapter (through JMS, sockets, db, etc.). You can see an example in the Portfolio Demo code (http://www.lightstreamer.com/portfolioDemo.htm).

Cheers

[vishnugs]

Hi Friends,

Thanks a lot for your support. I m now able to understand the architecture.

For my case, I just pass the name of the user to the adapter (to which it is subscribed). The server manages sending it only to him.

I have two more questions -

1) I tried modifying the engine creation to include username/password as follows
engineRef.context.setDebugAlertsOnClientError(debu gAlerts);
engineRef.context.setRemoteAlertsOnClientError(tru e);
engineRef.connection.setUserName("cookie");
engineRef.connection.setPassword("password");
engineRef.connection.setLSHost(host);
engineRef.connection.setLSPort(port);
engineRef.connection.setAdapterName("STOCKLISTJMSD EMO");
engineRef.changeStatus("STREAMING");
but I always get null for username argument in the following functions
LiteralBasedProvider::getItems
LiteralBasedProvider::getSchema
and username/password is null in the following function
LiteralBasedProvider::notifyUser

Am I going wrong somewhere?

2) Is there any other way of creating a client implementation to subscribe and receive messages from the server without using NonVisualTable control?

Thanks,

Vishnu

[DarioCrivelli]

Hi Vishnu

The username argument is supposed not to be passed as null in this case.
Is it possible that the Engine is already streaming when "setUserName" is called?
Are you using "createEngine" or the old "loadEngine" in order to load the Engine?
May you please check Lightstreamer Server log? You should be able to find your username logged.

I Assume that, in your second question, you are looking for an alternative to using "NonVisualTable" still in the context of an HTML front-end. Then the answer is no; subscribing to items is only made through the definition of a table object.
Other types of table objects do exist, as listed in the Javascript API JSDocs: they all are "visual tables" and can be used in order to take advantage of Lightstreamer-provided management of the visualization of the data in the table cells.

Dario