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You may also use the service methods to populate lists (for example DropDowns).
After service is registered, add a new data source as "Web Service Query".
Click on "Edit" button to edit the data source. Service method is now displayed on screen and specify input parameters.
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All standard SOAP headers are automatically handled by the system, but in some scenarios you may need to set additional SOAP headers transfer information.
While invoking service, after specifying request body you may give secondary object to as headers body. If service definition has matching header by name, specified value is imported to the SOAP message.
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Rest services does not provide any discovery information and are dynamically invoked.
Please refer to to the $Rest page to get information for consuming a rest service.