SH-4061 WIP - moved retry policy to newview so it can work with either llmessage or CoreHttp libraries. Updated tests.

1 files changed, 117 insertions, 0 deletions

diff --git a/indra/newview/llhttpretrypolicy.cpp b/indra/newview/llhttpretrypolicy.cpp
new file mode 100755
index 0000000000..5c6dabbe99
--- /dev/null
+++ b/indra/newview/llhttpretrypolicy.cpp
@@ -0,0 +1,117 @@
+/** 
+ * @file llhttpretrypolicy.h
+ * @brief Header for a retry policy class intended for use with http responders.
+ *
+ * $LicenseInfo:firstyear=2013&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2013, Linden Research, Inc.
+ * 
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * 
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+
+#include "llviewerprecompiledheaders.h"
+
+#include "llhttpretrypolicy.h"
+
+bool LLAdaptiveRetryPolicy::getRetryAfter(const LLSD& headers, F32& retry_header_time)
+{
+	return (headers.has(HTTP_IN_HEADER_RETRY_AFTER)
+			&& getSecondsUntilRetryAfter(headers[HTTP_IN_HEADER_RETRY_AFTER].asStringRef(), retry_header_time));
+}
+
+bool LLAdaptiveRetryPolicy::getRetryAfter(const LLCore::HttpHeaders *headers, F32& retry_header_time)
+{
+	// Look for matching header. Hopefully it's correct enough to let
+	// us extract the field we are looking for. Does not purport to be
+	// in any way a viable general HTTP header parser.
+	if (headers)
+	{
+		for (std::vector<std::string>::const_iterator it = headers->mHeaders.begin();
+			 it != headers->mHeaders.end();
+			 ++it)
+		{
+			const std::string& str = *it;
+			const std::string match = HTTP_IN_HEADER_RETRY_AFTER + ":";
+			size_t pos = str.find(match);
+			if ((pos != std::string::npos) &&
+				(pos+match.length() <= str.length()))
+			{
+				retry_header_time = strtod(str.substr(pos+match.length()).c_str(), NULL);
+				return true;
+			}
+		}
+	}
+	return false;
+}
+
+void LLAdaptiveRetryPolicy::onFailure(S32 status, const LLSD& headers)
+{
+	F32 retry_header_time;
+	bool has_retry_header_time = getRetryAfter(headers,retry_header_time);
+	onFailureCommon(status, has_retry_header_time, retry_header_time);
+}
+  
+// TODO: replace this parsing junk once CoreHttp has its own header parsing capabilities.
+void LLAdaptiveRetryPolicy::onFailure(const LLCore::HttpResponse *response)
+{
+	F32 retry_header_time;
+	const LLCore::HttpHeaders *headers = response->getHeaders();
+	bool has_retry_header_time = getRetryAfter(headers,retry_header_time);
+	onFailureCommon(response->getStatus().mType, has_retry_header_time, retry_header_time);
+}
+
+void LLAdaptiveRetryPolicy::onFailureCommon(S32 status, bool has_retry_header_time, F32 retry_header_time)
+{
+	if (mRetryCount > 0)
+	{
+		mDelay = llclamp(mDelay*mBackoffFactor,mMinDelay,mMaxDelay);
+	}
+	// Honor server Retry-After header.
+	// Status 503 may ask us to wait for a certain amount of time before retrying.
+	F32 wait_time = mDelay;
+	if (has_retry_header_time)
+	{
+		wait_time = retry_header_time;
+	}
+
+	if (mRetryCount>=mMaxRetries)
+	{
+		llinfos << "Too many retries " << mRetryCount << ", will not retry" << llendl;
+		mShouldRetry = false;
+	}
+	if (!isHttpServerErrorStatus(status))
+	{
+		llinfos << "Non-server error " << status << ", will not retry" << llendl;
+		mShouldRetry = false;
+	}
+	if (mShouldRetry)
+	{
+		llinfos << "Retry count " << mRetryCount << " should retry after " << wait_time << llendl;
+		mRetryTimer.reset();
+		mRetryTimer.setTimerExpirySec(wait_time);
+	}
+	mRetryCount++;
+}
+	
+
+bool LLAdaptiveRetryPolicy::shouldRetry(F32& seconds_to_wait) const
+{
+	llassert(mRetryCount>0); // have to call onFailure() before shouldRetry()
+	seconds_to_wait = mShouldRetry ? mRetryTimer.getRemainingTimeF32() : F32_MAX;
+	return mShouldRetry;
+}