Limitation of SmartGWT RestDataSource

[rshepherd]

While creating a simple client for a REST service which I have stubbed out, I noticed that smartGWT's RestDataSource class is limited in the type of xml it can understand. All REST resources must respond with XML in the following format..

<response>
  <status>0</status>
  <startRow>0</startRow>
  <endRow>10</endRow>
  <totalRows>50</totalRows>
  <data>
        <record>
            <someField>value</someField>
            <someOtherField>value</someOtherField>
        </record>
        <record>
            <someField>value</someField>
            <someOtherField>value</someOtherField> 
        </record>
        ...
  </data>
</response>

.. where the *only variant* is the someField/someOtherField tags.

This structure, which is little more than name/value pairs, is not going to work for us.

From the RestDataSource javadoc....

"If you have a pre-existing REST or WSDL service which is difficult to change, consider adapting Smart GWT to the existing service instead, by starting with a normal{@link com.smartgwt.client.data.DataSource} and using the {@link com.smartgwt.client.docs.ClientDataIntegration 'client-side data integration'} facilities to create a mapping between Smart GWT's {@link com.smartgwt.client.data.DSRequest} and {@link com.smartgwt.client.data.DSResponse} objects and the message formats of your existing services."

Has anyone out there done this? I am wondering if this approach has been battle-tested or not. I would love to see someone's solution. It sounds like it would require quite a bit of boilerplate code.

Thanks!

[Isomorphic]

It's very common and very simple.

[rshepherd]

Thank you sir. This is precisely what I was looking for.

[rshepherd]

Is there an example somewhere of how to do a PUT operation on a REST service?

[davidj6]

It can be done. Take a look at the datasource operationBindings. In particular look at the dataProtocol and requestProperties. You likely want postmessage for the protocol and need to add httpMethod of PUT to requestProperties.

[rshepherd]

OK getting very close...

    DataSource dataSource = new DataSource();
    dataSource.setRecordXPath("//default:Widget");
		
    // PUT				
    OperationBinding put = new OperationBinding(DSOperationType.ADD,"/SampleServer/widget/");
    put.setDataFormat(DSDataFormat.XML);
    put.setDataProtocol(DSProtocol.POSTXML);
    put.setRecordName("Widget");
		
    DSRequest putProps = new DSRequest();
    putProps.getUseSimpleHttp();
    putProps.setHttpMethod("PUT");
    put.setRequestProperties(putProps);

    // GET
    OperationBinding get = new OperationBinding(DSOperationType.FETCH,"/SampleServer/widget/");		
    
    dataSource.setOperationBindings(put,get);
    
    DataSourceTextField nameField = new DataSourceTextField("Name", "Name");
    DataSourceTextField priceField = new DataSourceTextField("Price", "Price");
    dataSource.setFields(nameField, priceField);

When attached to a grid this basically works.... the problem is that when performing a PUT the resulting request body looks like this...

<isc_OID_0>  
  <Name>asdfsd</Name>  
  <Price>1234</Price> 
</isc_OID_0>

Where my server expects the following...

<Widget>  
  <Name>asdfsd</Name>  
  <Price>1234</Price> 
</Widget>

I would have though setRecordName("Widget") would accomplish that, but apparently not.

[Isomorphic]

recordName is doc'd as being involved in response parsing. The DataSource ID, or alternatively dataSource.tagName, determines what happens on serialization of data.