Describes the format in which to request GetFeatureInfo from a Web Map Service (WMS) server.
    
| Name | Type | Description | 
|---|---|---|
type | 
            
            string | The type of response to expect from a GetFeatureInfo request. Valid values are 'json', 'xml', 'html', or 'text'. | 
format | 
            
            string | optional The info format to request from the WMS server. This is usually a MIME type such as 'application/json' or text/xml'. If this parameter is not specified, the provider will request 'json' using 'application/json', 'xml' using 'text/xml', 'html' using 'text/html', and 'text' using 'text/plain'. | 
callback | 
            
            function | 
            
                
                        optional
                
                
                
            
                A function to invoke with the GetFeatureInfo response from the WMS server
       in order to produce an array of picked ImageryLayerFeatureInfo instances.  If this parameter is not specified,
       a default function for the type of response is used. | 
        
