http://localhost:5555/invoke/pub.art/listRegisteredAdapters gives me the output in HTML format. How can I get this into text file without HTML tags
the output format depends on how the service is being invoked.
When invoking via Browser like in your example the "Test " page wraps the output of the service into a DSP-formatted page dispalyed as an HTML page.
When invoked by another service there will be just a pipeline object containing the results.
You can explore the output templates section on the property of the flow service. Read documentation on it.
You could also use the service pub.flow:setResponse at the end of the flow service and set the content type to “text”.