Support range requests and seekable streams

Untangle streams/streamPresenter/writableContent
Pass the ExecContext into more bits of content interface

4 files changed, 52 insertions, 1 deletions

diff --git a/project2/cgi/cgiRequestContext.cpp b/project2/cgi/cgiRequestContext.cpp
index d38a256..2827aa7 100644
--- a/project2/cgi/cgiRequestContext.cpp
+++ b/project2/cgi/cgiRequestContext.cpp
@@ -8,6 +8,7 @@
 #include <map>
 #include <cgicc/Cgicc.h>
 #include <curl/curl.h>
+#include <boost/lexical_cast.hpp>
 #include <boost/uuid/uuid_io.hpp>
 #include <boost/uuid/uuid_generators.hpp>
 
@@ -120,3 +121,26 @@ CgiRequestContext::getParameter(const VariableType & p) const
 	return cgi(p);
 }
 
+boost::optional<RangeRequest>
+CgiRequestContext::getRequestRange() const
+{
+	const auto r = cgienv.getenv("HTTP_RANGE");
+	std::vector<std::string> rangeParts;
+	boost::split(rangeParts, r, boost::is_any_of("=-"), boost::algorithm::token_compress_off);
+
+	if (rangeParts.size() < 3 || (rangeParts[1].empty() && rangeParts[2].empty())) {
+		return boost::optional<RangeRequest>();
+	}
+	RangeRequest range;
+	range.Unit = rangeParts[0];
+
+	if (!rangeParts[1].empty()) {
+		range.Start = boost::lexical_cast<RangePos>(rangeParts[1]);
+	}
+	if (!rangeParts[2].empty()) {
+		range.End = boost::lexical_cast<RangePos>(rangeParts[2]);
+	}
+
+	return range;
+}
+
diff --git a/project2/cgi/cgiRequestContext.h b/project2/cgi/cgiRequestContext.h
index 57c233d..9501a20 100644
--- a/project2/cgi/cgiRequestContext.h
+++ b/project2/cgi/cgiRequestContext.h
@@ -6,6 +6,7 @@
 #include "cgiEnvInput.h"
 #include "cgiRouter.h"
 #include "execContext.h"
+#include <range.h>
 #include <cgicc/CgiEnvironment.h>
 #include <cgicc/Cgicc.h>
 #include <lazyPointer.h>
@@ -40,6 +41,7 @@ class CgiRequestContext : public ExecContext {
 		ETags getRequestETags() const;
 		time_t getRequestModifiedSince() const;
 		std::string getCookieValue(const std::string & name) const;
+		boost::optional<RangeRequest> getRequestRange() const;
 		LazyPointer<Router> router;
 
 		boost::posix_time::ptime startTime;
diff --git a/project2/cgi/cgiResultWritable.cpp b/project2/cgi/cgiResultWritable.cpp
index 357a57c..1364456 100644
--- a/project2/cgi/cgiResultWritable.cpp
+++ b/project2/cgi/cgiResultWritable.cpp
@@ -4,8 +4,32 @@
 class WritableToCgiResult : public TransformImpl<WritableContent, CgiResult> {
 	public:
 		void transform(const WritableContent * wc, CgiResult * cr, ExecContext * ec) const {
-			cr->header->addHeader("Content-Type", Glib::ustring::compose("%1; charset=%2", wc->getContentType(), cr->encoding));
+			cr->header->addHeader("Content-Type", Glib::ustring::compose("%1; charset=%2", wc->getContentType(ec), cr->encoding));
 			cr->header->addHeader("Cache-control", "no-cache");
+			auto size = wc->getSizeInBytes(ec);
+			if (size) {
+				auto range = wc->getRange(ec);
+				if (range) {
+					cr->header->addHeader("Status", "206 Partial Content");
+					cr->header->addHeader("Content-Length", Glib::ustring::compose("%1", range->End - range->Start + 1));
+					cr->header->addHeader("Content-Range", Glib::ustring::compose("%1 %2-%3/%4",
+								range->Unit, range->Start, range->End, *size));
+				}
+				else {
+					cr->header->addHeader("Content-Length", Glib::ustring::compose("%1", *size));
+				}
+			}
+			if (wc->isSeekable()) {
+				cr->header->addHeader("Accept-Ranges", "bytes");
+			}
+			auto modifiedTime = wc->getModifiedTime(ec);
+			if (modifiedTime) {
+				char buf[100];
+				struct tm stm;
+				gmtime_r(&*modifiedTime, &stm);
+				strftime(buf, sizeof(buf), "%a, %d %b %Y %T %z", &stm);
+				cr->header->addHeader("Last-Modified", buf);
+			}
 			cr->header->render(cr->stream);
 			wc->writeTo(cr->stream, cr->encoding, ec);
 		}
diff --git a/project2/cgi/testCgi.cpp b/project2/cgi/testCgi.cpp
index 6644102..0c2b472 100644
--- a/project2/cgi/testCgi.cpp
+++ b/project2/cgi/testCgi.cpp
@@ -125,6 +125,7 @@ TESTOPT("HTTP_REFERER", "", "Referrer")
 TESTOPT("HTTP_COOKIE", "", "Cookie")
 TESTOPT("HTTPS", "No", "HTTPS?")
 TESTOPT("HTTP_IF_MODIFIED_SINCE", "", "Client cached copy timestamp")
+TESTOPT("HTTP_RANGE", "", "Range requested by client '{unit}=[start]-[end]'")
 ("urlListFile", Options::value(&urlListFile, ""), "Load URL list from this file")
 ("runCount", Options::value(&runCount, 1), "Repeat run this many times")
 ("help", ShowHelpComponent::Option(), "Print usage and exit")("h")