@Beta
    public DocumentProcessor.Progress process(String chain, final DocumentOperation op) {
        return application.getJDisc("default").documentProcessing().process(ComponentSpecification.fromString(chain),
                                                                            Processing.of(op));
    }
Process a single document through the default chain.

@param chain process using this chain
@param op the document operation to process
@return the docproc return status
application/src/test/java/com/yahoo/application/ApplicationFacade.java