Revamped external execute function into a external text formatter function

* importing XML output of a called executable into the result document required special logic which clashed with a general execute function
* general execute function may be implemented in the future
** support for external text formatters with XML output has a higher priority
* current implementation enables calling a markdown parser and including the XHTML output into the document

2 files changed, 46 insertions, 20 deletions

diff --git a/src/function/execute.cc b/src/function/external_text_formatter.cc
index f19ba75..d1b9e92 100644
--- a/src/function/execute.cc
+++ b/src/function/external_text_formatter.cc
@@ -1,21 +1,52 @@
-#include "execute.h"
+#include "external_text_formatter.h"
+
+#include <xalanc/XSLT/XSLTInputSource.hpp>
 
 #include <xercesc/dom/DOMDocument.hpp>
 #include <xercesc/dom/DOMImplementation.hpp>
 #include <xercesc/dom/DOMElement.hpp>
+#include <xercesc/parsers/XercesDOMParser.hpp>
 
 #include <boost/process.hpp>
 
+#include <sstream>
+
 #include "support/xerces_string_guard.h"
 #include "support/dom/result_node_facade.h"
 
+namespace {
+
+using InputXSLT::XercesStringGuard;
+
+inline xercesc::DOMNode* importDocumentElement(
+	boost::process::pistream& outputStream,
+	xercesc::DOMDocument* const domDocument
+) {
+	std::stringstream xmlStream(
+		"<output>" + std::string(
+			(std::istreambuf_iterator<char>(outputStream)),
+			(std::istreambuf_iterator<char>())
+		) + "</output>"
+	);
+
+	xercesc::XercesDOMParser parser;
+	parser.parse(xalan::XSLTInputSource(xmlStream));
+
+	return domDocument->importNode(
+		parser.getDocument()->getDocumentElement(),
+		true
+	);
+}
+
+}
+
 namespace InputXSLT {
 
-xercesc::DOMDocument* FunctionExecute::constructDocument(
+xercesc::DOMDocument* FunctionExternalTextFormatter::constructDocument(
 	const InputXSLT::FilesystemContext&,
 	const FunctionBase::parameter_tuple& parameters
 ) {
-	const std::string& executablePath(
+	const std::string& formatterPath(
 		std::get<0>(parameters)
 	);
 
@@ -39,32 +70,27 @@ xercesc::DOMDocument* FunctionExecute::constructDocument(
 	context.stdout_behavior = boost::process::capture_stream();
 	context.stdin_behavior  = boost::process::capture_stream();
 
-	boost::process::child process(
+	boost::process::child formatterProcess(
 		boost::process::launch(
-			executablePath,
+			formatterPath,
 			std::vector<std::string>{""},
 			context
 		)
 	);
 
-	boost::process::postream& inputStream  = process.get_stdin();
-	boost::process::pistream& outputStream = process.get_stdout();
+	boost::process::postream& inputStream  = formatterProcess.get_stdin();
+	boost::process::pistream& outputStream = formatterProcess.get_stdout();
 
 	inputStream << stdinText;
 	inputStream.close();
 
-	const std::string resultText(
-		(std::istreambuf_iterator<char>(outputStream)),
-		(std::istreambuf_iterator<char>())
-	);
-
-	boost::process::status status = process.wait();
+	boost::process::status status = formatterProcess.wait();
 
 	if ( status.exited() ) {
 		ResultNodeFacade result(domDocument, rootNode, "result");
 
-		result.setValueNode("code",   std::to_string(status.exit_status()));
-		result.setValueNode("output", resultText);
+		result.setValueNode("code", std::to_string(status.exit_status()));
+		result.setContent(importDocumentElement(outputStream, domDocument));
 	} else {
 		ResultNodeFacade result(domDocument, rootNode, "error");
 
diff --git a/src/function/execute.h b/src/function/external_text_formatter.h
index 12167da..877bac5 100644
--- a/src/function/execute.h
+++ b/src/function/external_text_formatter.h
@@ -1,12 +1,12 @@
-#ifndef INPUTXSLT_SRC_FUNCTION_EXECUTE_H_
-#define INPUTXSLT_SRC_FUNCTION_EXECUTE_H_
+#ifndef INPUTXSLT_SRC_FUNCTION_EXTERNAL_TEXT_FORMATTER_H_
+#define INPUTXSLT_SRC_FUNCTION_EXTERNAL_TEXT_FORMATTER_H_
 
 #include "base.h"
 
 namespace InputXSLT {
 
-class FunctionExecute : public FunctionBase<
-	FunctionExecute,
+class FunctionExternalTextFormatter : public FunctionBase<
+	FunctionExternalTextFormatter,
 	std::string,
 	std::string
 > {
@@ -25,4 +25,4 @@ class FunctionExecute : public FunctionBase<
 
 }
 
-#endif  // INPUTXSLT_SRC_FUNCTION_EXECUTE_H_
+#endif  // INPUTXSLT_SRC_FUNCTION_EXTERNAL_TEXT_FORMATTER_H_