JSClient

Overview

The JSClient serves as a wrapper for a headless client, providing tools to interact with the headless client plugin. Constants like CALLBACK_EVENT and CALLBACK_EXCEPTION_EVENT help identify whether callback execution was successful or if an exception occurred.

The client enables several functionalities, such as retrieving its unique client ID, which can be used for identifying or managing the client. It supports accessing or modifying data provider values based on a specified context or active method call, ensuring precise value management.

The client allows for queuing method calls on the remote server, with / without a callbacks.Validation checks ensure that the client is still active and usable, while methods are available to gracefully or forcefully shut down the client as required.

Constants Summarized

Type	Name	Summary
String	CALLBACK_EVENT	Constant that is returned as a JSEvent type when in the callback method when it executed normally.
String	CALLBACK_EXCEPTION_EVENT	Constant that is returned as a JSEvent type when in the callback method when an exception occurred.

Methods Summarized

Type	Name	Summary
String	getClientID()	Gets the id of the client.
Object	getDataProviderValue(contextName, dataprovider)	Get a data-provider value.
Object	getDataProviderValue(contextName, dataprovider, methodName)	Get a data-provider value.
Boolean	isValid()	returns true if this client is still valid/usable.
void	queueMethod(contextName, methodName, args)	Queues a method call on the remote server, without a callback method.
void	queueMethod(contextName, methodName, args, notifyCallBackMethod)	Queues a method call on the remote server.
Object	setDataProviderValue(contextName, dataprovider, value)	Set a data-provider value.
Object	setDataProviderValue(contextName, dataprovider, value, methodName)	Set a data-provider value.
void	shutdown()	closes the client.
void	shutdown(force)	closes the client.

Constants Detailed

CALLBACK_EVENT

Constant that is returned as a JSEvent type when in the callback method when it executed normally.

Type String

Sample

if (jsclient && jsclient.isValid())
{
	/*Queue a method where the callback can do something like this
	if (event.getType() == JSClient.CALLBACK_EVENT)
	{
		application.output("callback data, name: " + event.data);
	}
	else if (event.getType() == JSClient.CALLBACK_EXCEPTION_EVENT)
	{
		application.output("exception callback, name: " + event.data);
	}*/
	var x = new Object();
	x.name = 'remote1';
	x.number = 10;
	// this calls a 'remoteMethod' on the server as a global method, because the context (first argument is set to null), you can use a formname to call a form method
	jsclient.queueMethod(null, "remoteMethod", [x], callback);
}

CALLBACK_EXCEPTION_EVENT

Constant that is returned as a JSEvent type when in the callback method when an exception occurred.

Type String

Sample

if (jsclient && jsclient.isValid())
{
	/*Queue a method where the callback can do something like this
	if (event.getType() == JSClient.CALLBACK_EVENT)
	{
		application.output("callback data, name: " + event.data);
	}
	else if (event.getType() == JSClient.CALLBACK_EXCEPTION_EVENT)
	{
		application.output("exception callback, name: " + event.data);
	}*/
	var x = new Object();
	x.name = 'remote1';
	x.number = 10;
	// this calls a 'remoteMethod' on the server as a global method, because the context (first argument is set to null), you can use a formname to call a form method
	jsclient.queueMethod(null, "remoteMethod", [x], callback);
}

Methods Detailed

getClientID()

Gets the id of the client.

This client id can be used to find the client from the headless client plugin. Note that this client id is not the same id as the id displayed on the Aplicationb Server admin page.

Returns: String The unique identifier of the client, which can be used to locate the client via the headless client plugin.

Sample

var headlessClient = plugins.headlessclient.createClient("someSolution", "user", "pass", null);
var clientID = headlessClient.getClientID()
....
headlessClient = plugins.headlessclient.getClient(clientID);
if (headlessClient != null && headlessClient.isValid()) {
	 headlessClient.queueMethod(null, "someRemoteMethod", null, callback);
}

getDataProviderValue(contextName, dataprovider)

Get a data-provider value.

Parameters

• String contextName The context of the given method, null if it is global method or a form name for a form method

• String dataprovider the data-provider name as seen in Servoy

Returns: Object the value for the data-provider.

Sample

if (jsclient && jsclient.isValid())
{
	// only gets the globals.media when the 'remoteMethod' is currently executing for this client
	var value = jsclient.getDataProviderValue(null, "scopes.globals.number", 'remoteMethod');
	if (value != null)
	{
		application.output("value get from scopes.globals.number :: "+ value);
		scopes.globals.value = value+10;
		var returnValue = jsclient.setDataProviderValue(null, "scopes.globals.number", scopes.globals.value, 'remoteMethod');
		application.output("value set to scopes.globals.number previous value "+ returnValue);
	}
	else
	{
		application.output("value get from scopes.globals.number :: " + null);
	}
}

getDataProviderValue(contextName, dataprovider, methodName)

Get a data-provider value.

Parameters

• String contextName The context of the given method; null if it is global method or a form name for a form method.

• String dataprovider the data-provider name as seen in Servoy.

• String methodName if this is specified, the data-provider's value will only be returned if the specified method is running in this headless client because the currently running client requested it to. Otherwise undefined is returned.

Returns: Object the value of the data-provider.

Sample

if (jsclient && jsclient.isValid())
{
	// only gets the globals.media when the 'remoteMethod' is currently executing for this client
	var value = jsclient.getDataProviderValue(null, "scopes.globals.number", 'remoteMethod');
	if (value != null)
	{
		application.output("value get from scopes.globals.number :: "+ value);
		scopes.globals.value = value+10;
		var returnValue = jsclient.setDataProviderValue(null, "scopes.globals.number", scopes.globals.value, 'remoteMethod');
		application.output("value set to scopes.globals.number previous value "+ returnValue);
	}
	else
	{
		application.output("value get from scopes.globals.number :: " + null);
	}
}

isValid()

returns true if this client is still valid/usable.

Returns: Boolean True if the client is still valid and usable; false otherwise.

Sample

if (jsclient && jsclient.isValid())
{
	/*Queue a method where the callback can do something like this
	if (event.getType() == JSClient.CALLBACK_EVENT)
	{
		application.output("callback data, name: " + event.data);
	}
	else if (event.getType() == JSClient.CALLBACK_EXCEPTION_EVENT)
	{
		application.output("exception callback, name: " + event.data);
	}*/
	var x = new Object();
	x.name = 'remote1';
	x.number = 10;
	// this calls a 'remoteMethod' on the server as a global method, because the context (first argument is set to null), you can use a formname to call a form method
	jsclient.queueMethod(null, "remoteMethod", [x], callback);
}

queueMethod(contextName, methodName, args)

Queues a method call on the remote server, without a callback method. Please note that calling queueMethod without a callback does not return anything: no result of the remote method or no exception if something went wrong.

Parameters

• String contextName The context of the given method, null if it is global method or a form name for a form method.

• String methodName The method name.

• Array args The arguments that should be passed to the method.

Returns: void

Sample

if (jsclient && jsclient.isValid())
{
	var x = new Object();
	x.name = 'remote1';
	x.number = 10;
	// this calls a 'remoteMethod' on the server as a global method, because the context (first argument is set to null), you can use a formname to call a form method
	jsclient.queueMethod(null, "remoteMethod", [x]);
}

queueMethod(contextName, methodName, args, notifyCallBackMethod)

Queues a method call on the remote server. The callback method will be called when the method is executed on the server and the return value is given as the JSEvent.data object with the JSEvent.getType() value of JSClient.CALLBACK_EVENT. If an exception is thrown somewhere then the callback method will be called with the exception as the JSEvent data object with the JSEvent.getType() value of JSClient.CALLBACK_EXCEPTION_EVENT The second argument that is give back is the JSClient instance that did the call.

Parameters

• String contextName The context of the given method, null if it is global method or a form name for a form method.

• String methodName The method name.

• Array args The arguments that should be passed to the method.

• Function notifyCallBackMethod The callback method that is called when the execution is finished.

Returns: void

Sample

if (jsclient && jsclient.isValid())
{
	/*Queue a method where the callback can do something like this
	if (event.getType() == JSClient.CALLBACK_EVENT)
	{
		application.output("callback data, name: " + event.data);
	}
	else if (event.getType() == JSClient.CALLBACK_EXCEPTION_EVENT)
	{
		application.output("exception callback, name: " + event.data);
	}*/
	var x = new Object();
	x.name = 'remote1';
	x.number = 10;
	// this calls a 'remoteMethod' on the server as a global method, because the context (first argument is set to null), you can use a formname to call a form method
	jsclient.queueMethod(null, "remoteMethod", [x], callback);
}

setDataProviderValue(contextName, dataprovider, value)

Set a data-provider value.

Parameters

• String contextName The context of the given method, null if it is global method or a form name for a form method.

• String dataprovider the data-provider name as seen in Servoy.

• Object value the value to set.

Returns: Object the old value or null if no change.

Sample

if (jsclient && jsclient.isValid())
{
	// only gets the globals.media when the 'remoteMethod' is currently executing for this client
	var value = jsclient.getDataProviderValue(null, "scopes.globals.number", 'remoteMethod');
	if (value != null)
	{
		application.output("value get from scopes.globals.number :: "+ value);
		scopes.globals.value = value+10;
		var returnValue = jsclient.setDataProviderValue(null, "scopes.globals.number", scopes.globals.value, 'remoteMethod');
		application.output("value set to scopes.globals.number previous value "+ returnValue);
	}
	else
	{
		application.output("value get from scopes.globals.number :: " + null);
	}
}

setDataProviderValue(contextName, dataprovider, value, methodName)

Set a data-provider value.

Parameters

• String contextName The context of the given method, null if it is global method or a form name for a form method

• String dataprovider the data-provider name as seen in Servoy

• Object value the value to set

• String methodName if this is specified, the data-provider's value will only be set if the specified method is running in this headless client because the currently running client requested it to. Otherwise the value is not set into the data-provider and undefined is returned.

Returns: Object the old value or null if no change

Sample

if (jsclient && jsclient.isValid())
{
	// only gets the globals.media when the 'remoteMethod' is currently executing for this client
	var value = jsclient.getDataProviderValue(null, "scopes.globals.number", 'remoteMethod');
	if (value != null)
	{
		application.output("value get from scopes.globals.number :: "+ value);
		scopes.globals.value = value+10;
		var returnValue = jsclient.setDataProviderValue(null, "scopes.globals.number", scopes.globals.value, 'remoteMethod');
		application.output("value set to scopes.globals.number previous value "+ returnValue);
	}
	else
	{
		application.output("value get from scopes.globals.number :: " + null);
	}
}

shutdown()

closes the client.

Returns: void

Sample

if (jsclient && jsclient.isValid())
{
	/*Queue a method where the callback can do something like this
	if (event.getType() == JSClient.CALLBACK_EVENT)
	{
		application.output("callback data, name: " + event.data);
	}
	else if (event.getType() == JSClient.CALLBACK_EXCEPTION_EVENT)
	{
		application.output("exception callback, name: " + event.data);
	}*/
	var x = new Object();
	x.name = 'remote1';
	x.number = 10;
	// this calls a 'remoteMethod' on the server as a global method, because the context (first argument is set to null), you can use a formname to call a form method
	jsclient.queueMethod(null, "remoteMethod", [x], callback);
}

shutdown(force)

closes the client.

Parameters

• Boolean force ;

Returns: void

Sample

if (jsclient && jsclient.isValid())
{
	/*Queue a method where the callback can do something like this
	if (event.getType() == JSClient.CALLBACK_EVENT)
	{
		application.output("callback data, name: " + event.data);
	}
	else if (event.getType() == JSClient.CALLBACK_EXCEPTION_EVENT)
	{
		application.output("exception callback, name: " + event.data);
	}*/
	var x = new Object();
	x.name = 'remote1';
	x.number = 10;
	// this calls a 'remoteMethod' on the server as a global method, because the context (first argument is set to null), you can use a formname to call a form method
	jsclient.queueMethod(null, "remoteMethod", [x], callback);
}

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