Proper use of Batch Update against XML web service?

[Steven]

I am hoping someone can shed some light on the proper method for handling batch updates on a grid when the backend data source is an XML based web service.

Here are the particulars:

I would like to use the built in update, create and delete properties of the datasource transport, at the same time, I need to manipulate the data being sent to the web service from json to xml (the reader is json, the writer is xml).   The caveat to this is I need to update the actual cell value being updated not a whole record (model) at a time.   The problem with doing this strictly in the datasource (as far as I can tell) is that I cannot get details about which column changed only that the record (model) was updated.

Is there a way without putting in handlers within the KendoGrid to identify which fields have changed during the parameterMap callback so I can output just those individual values that have changed in a batch mode?


Here is what I did, but I would like to avoid putting a handler in the grid (if possible):

I put an event handler off the save property of the KendoGrid to record a list of changed cells.   Then, on the ParameterMap of the data source, I go through the records and build the proper xml.  


Is this the right approach or is there a better way to do this all within the datasource?

Here is my KendoGrid definition:

$(this._renderTo).kendoGrid({

    dataSource: this.ItemsDS,

    sortable: true,

    pageable: true,

    navigatable: true,

    editable: true,

    save: $.proxy( this.onCellChanged, this ),

    columns: [

        { field: "Position.Name", title: "Position", width: 20 },

        { field: "Headcount.value", title: "Headcount", width: 15 },

        { field: "FTE.value", title: "FTE", width: 15 },

        { field: "EmployeeName.value", title: "EmployeeName", width: 50 },

        { field: "JobCode.value", title: "JobCode", width: 20 },

        { field: "JobTitle.value", title: "JobTitle", width: 100 }

    ]

});

Then, the onCellChanged:

onCellChanged: function (e) {

    var isDirty = false;

 

    var fieldName = e.container[0].firstChild.name;

    if (!fieldName)

        return;

 

    var newValue = e.values[fieldName];

    var oldValue = e.model[fieldName]

 

    if (newValue != oldValue) {

        var esResults = this.ItemsDS._pristine.EmployeeListResponse.Results;

        elemName = fieldName;

 

        // Create the record that will be sent back to TM1

        this._employeeUpdates.items.push({

            Scenario:       esResults.Scenario,

            Position:       e.model.Position,

            Employee:       e.model.Employee,

            EntityDept:     esResults.EntityDept,

            ProductLine_s:  esResults.ProductLine_s,

            Employee_m:     { ID: elemName },

            Value:          newValue

        });

 

        e.container.data("oldValue", newValue);

    }

},

And the datasource definition

this.ItemsDS = new kendo.data.DataSource({

    transport: {

        read: {

            url: this._url + "/EmployeeList",

            dataType: "json"

        },

        update: {

            url: this._url + "/TM1ViewWrite",

            dataType: "xml"

        },

        parameterMap: $.proxy(this._crudItemDS, this)                           

    },

    pageSize: 15,

    schema: {

       :     :    :    :    :

And finally the parameterMap (crud operations):

_crudItemDS: function (options, operation) {

    if (operation == "update") {

        if (this._employeeUpdates) {

            return { events: kendo.stringify(this._employeeUpdates) };

        };

    }

    return null;

},

[Alexander Valchev]

Hello Steven,

Your approach and code snippets looks OK.
This functionality is not supported out of the box and I cannot suggest a way to implement this only through the dataSource API without putting a handler in the grid.

Greetings,
Alexander Valchev
the Telerik team