DEV-49633 fixed, use Cache-Control max-age for display name expiration

We have no C++ libraries for parsing RFC 1123 dates, so parsing "Expires"
headers is risky.  max-age delta-seconds is easier to parse and equivalent
for this use.  Also added unit tests for max-age parsing.  Pair-programmed
with Huseby.

4 files changed, 206 insertions, 26 deletions

diff --git a/indra/llmessage/CMakeLists.txt b/indra/llmessage/CMakeLists.txt
index 0d07015f24..1cad0f6d22 100644
--- a/indra/llmessage/CMakeLists.txt
+++ b/indra/llmessage/CMakeLists.txt
@@ -250,6 +250,7 @@ if (LL_TESTS)
     "${CMAKE_CURRENT_SOURCE_DIR}/tests/test_llsdmessage_peer.py"
     )
 
+  LL_ADD_INTEGRATION_TEST(llavatarnamecache "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(llhost "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(llpartdata "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(llxfer_file "" "${test_libs}")
diff --git a/indra/llmessage/llavatarnamecache.cpp b/indra/llmessage/llavatarnamecache.cpp
index 560d0f48cf..701f3931d0 100644
--- a/indra/llmessage/llavatarnamecache.cpp
+++ b/indra/llmessage/llavatarnamecache.cpp
@@ -40,6 +40,8 @@
 #include "llsd.h"
 #include "llsdserialize.h"
 
+#include <boost/tokenizer.hpp>
+
 #include <map>
 #include <set>
 
@@ -185,19 +187,8 @@ public:
 
 	/*virtual*/ void result(const LLSD& content)
 	{
-		const F64 DEFAULT_EXPIRES = 24.0 * 60.0 * 60.0;
-		F64 now = LLFrameTimer::getTotalSeconds();
-
-		// With no expiration info, default to a day
-		F64 expires = now + DEFAULT_EXPIRES;
-
-		// Allow the header to override the default
-		LLSD expires_header = mHeaders["expires"];
-		if (expires_header.isDefined())
-		{
-			LLDate expires_date = expires_header.asDate();
-			expires = expires_date.secondsSinceEpoch();
-		}
+		// Pull expiration out of headers if available
+		F64 expires = LLAvatarNameCache::nameExpirationFromHeaders(mHeaders);
 
 		LLSD agents = content["agents"];
 		LLSD::array_const_iterator it = agents.beginArray();
@@ -209,19 +200,8 @@ public:
 			LLAvatarName av_name;
 			av_name.fromLLSD(row);
 
-			// *TODO: Remove this once People API starts passing "Expires:"
-			// headers.
-			// Prefer per-row data for expiration times
-			LLSD expires_row = row["display_name_expires"];
-			if (expires_row.isDefined())
-			{
-				LLDate expires_date = expires_row.asDate();
-				av_name.mExpires = expires_date.secondsSinceEpoch();
-			}
-			else
-			{
-				av_name.mExpires = expires;
-			}
+			// Use expiration time from header
+			av_name.mExpires = expires;
 
 			// Some avatars don't have explicit display names set
 			if (av_name.mDisplayName.empty())
@@ -700,3 +680,84 @@ void LLAvatarNameCache::insert(const LLUUID& agent_id, const LLAvatarName& av_na
 	// *TODO: update timestamp if zero?
 	sCache[agent_id] = av_name;
 }
+
+F64 LLAvatarNameCache::nameExpirationFromHeaders(LLSD headers)
+{
+	// With no expiration info, default to a day
+	const F64 DEFAULT_EXPIRES = 24.0 * 60.0 * 60.0;
+	F64 now = LLFrameTimer::getTotalSeconds();
+	F64 expires = now + DEFAULT_EXPIRES;
+
+	// Allow the header to override the default
+	LLSD cache_control_header = headers["cache-control"];
+	if (cache_control_header.isDefined())
+	{
+		S32 max_age = 0;
+		std::string cache_control = cache_control_header.asString();
+		if (max_age_from_cache_control(cache_control, &max_age))
+		{
+			expires = now + (F64)max_age;
+		}
+	}
+	return expires;
+}
+
+static const std::string MAX_AGE("max-age");
+static const boost::char_separator<char> EQUALS_SEPARATOR("=");
+static const boost::char_separator<char> COMMA_SEPARATOR(",");
+
+bool max_age_from_cache_control(const std::string& cache_control, S32 *max_age)
+{
+	// Split the string on "," to get a list of directives
+	typedef boost::tokenizer<boost::char_separator<char> > tokenizer;
+	tokenizer directives(cache_control, COMMA_SEPARATOR);
+
+	tokenizer::iterator token_it = directives.begin();
+	for ( ; token_it != directives.end(); ++token_it)
+	{
+		// Tokens may have leading or trailing whitespace
+		std::string token = *token_it;
+		LLStringUtil::trim(token);
+
+		if (token.compare(0, MAX_AGE.size(), MAX_AGE) == 0)
+		{
+			// ...this token starts with max-age, so let's chop it up by "="
+			tokenizer subtokens(token, EQUALS_SEPARATOR);
+			tokenizer::iterator subtoken_it = subtokens.begin();
+
+			// Must have a token
+			if (subtoken_it == subtokens.end()) return false;
+			std::string subtoken = *subtoken_it;
+
+			// Must exactly equal "max-age"
+			LLStringUtil::trim(subtoken);
+			if (subtoken != MAX_AGE) return false;
+
+			// Must have another token
+			++subtoken_it;
+			if (subtoken_it == subtokens.end()) return false;
+			subtoken = *subtoken_it;
+
+			// Must be a valid integer
+			// *NOTE: atoi() returns 0 for invalid values, so we have to
+			// check the string first.
+			// *TODO: Do servers ever send "0000" for zero?  We don't handle it
+			LLStringUtil::trim(subtoken);
+			if (subtoken == "0")
+			{
+				*max_age = 0;
+				return true;
+			}
+			S32 val = atoi( subtoken.c_str() );
+			if (val > 0 && val < S32_MAX)
+			{
+				*max_age = val;
+				return true;
+			}
+			return false;
+		}
+	}
+	return false;
+}
+
+
diff --git a/indra/llmessage/llavatarnamecache.h b/indra/llmessage/llavatarnamecache.h
index 26cecc5ab5..0a8b987b05 100644
--- a/indra/llmessage/llavatarnamecache.h
+++ b/indra/llmessage/llavatarnamecache.h
@@ -89,6 +89,15 @@ namespace LLAvatarNameCache
 	void fetch(const LLUUID& agent_id);
 
 	void insert(const LLUUID& agent_id, const LLAvatarName& av_name);
+
+	// Compute name expiration time from HTTP Cache-Control header,
+	// or return default value, in seconds from epoch.
+	F64 nameExpirationFromHeaders(LLSD headers);
 }
 
+// Parse a cache-control header to get the max-age delta-seconds.
+// Returns true if header has max-age param and it parses correctly.
+// Exported here to ease unit testing.
+bool max_age_from_cache_control(const std::string& cache_control, S32 *max_age);
+
 #endif
diff --git a/indra/llmessage/tests/llavatarnamecache_test.cpp b/indra/llmessage/tests/llavatarnamecache_test.cpp
new file mode 100644
index 0000000000..eeadb703d1
--- /dev/null
+++ b/indra/llmessage/tests/llavatarnamecache_test.cpp
@@ -0,0 +1,109 @@
+/**
+ * @file llhost_test.cpp
+ * @author Adroit
+ * @date 2007-02
+ * @brief llhost test cases.
+ *
+ * $LicenseInfo:firstyear=2007&license=viewergpl$
+ * 
+ * Copyright (c) 2007-2009, Linden Research, Inc.
+ * 
+ * Second Life Viewer Source Code
+ * The source code in this file ("Source Code") is provided by Linden Lab
+ * to you under the terms of the GNU General Public License, version 2.0
+ * ("GPL"), unless you have obtained a separate licensing agreement
+ * ("Other License"), formally executed by you and Linden Lab.  Terms of
+ * the GPL can be found in doc/GPL-license.txt in this distribution, or
+ * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
+ * 
+ * There are special exceptions to the terms and conditions of the GPL as
+ * it is applied to this Source Code. View the full text of the exception
+ * in the file doc/FLOSS-exception.txt in this software distribution, or
+ * online at
+ * http://secondlifegrid.net/programs/open_source/licensing/flossexception
+ * 
+ * By copying, modifying or distributing this software, you acknowledge
+ * that you have read and understood your obligations described above,
+ * and agree to abide by those obligations.
+ * 
+ * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
+ * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
+ * COMPLETENESS OR PERFORMANCE.
+ * $/LicenseInfo$
+ */
+ 
+#include "linden_common.h"
+
+#include "../llavatarnamecache.h"
+
+#include "../test/lltut.h"
+
+namespace tut
+{
+	struct avatarnamecache_data
+	{
+	};
+	typedef test_group<avatarnamecache_data> avatarnamecache_test;
+	typedef avatarnamecache_test::object avatarnamecache_object;
+	tut::avatarnamecache_test avatarnamecache_testcase("llavatarnamecache");
+
+	template<> template<>
+	void avatarnamecache_object::test<1>()
+	{
+		bool valid = false;
+		S32 max_age = 0;
+
+		valid = max_age_from_cache_control("max-age=3600", &max_age);
+		ensure("typical input valid", valid);
+		ensure_equals("typical input parsed", max_age, 3600);
+
+		valid = max_age_from_cache_control(
+			" max-age=600 , no-cache,private=\"stuff\" ", &max_age);
+		ensure("complex input valid", valid);
+		ensure_equals("complex input parsed", max_age, 600);
+
+		valid = max_age_from_cache_control(
+			"no-cache, max-age = 123 ", &max_age);
+		ensure("complex input 2 valid", valid);
+		ensure_equals("complex input 2 parsed", max_age, 123);
+	}
+
+	template<> template<>
+	void avatarnamecache_object::test<2>()
+	{
+		bool valid = false;
+		S32 max_age = -1;
+
+		valid = max_age_from_cache_control("", &max_age);
+		ensure("empty input returns invalid", !valid);
+		ensure_equals("empty input doesn't change val", max_age, -1);
+
+		valid = max_age_from_cache_control("no-cache", &max_age);
+		ensure("no max-age field returns invalid", !valid);
+
+		valid = max_age_from_cache_control("max", &max_age);
+		ensure("just 'max' returns invalid", !valid);
+
+		valid = max_age_from_cache_control("max-age", &max_age);
+		ensure("partial max-age is invalid", !valid);
+
+		valid = max_age_from_cache_control("max-age=", &max_age);
+		ensure("longer partial max-age is invalid", !valid);
+
+		valid = max_age_from_cache_control("max-age=FOO", &max_age);
+		ensure("invalid integer max-age is invalid", !valid);
+
+		valid = max_age_from_cache_control("max-age 234", &max_age);
+		ensure("space separated max-age is invalid", !valid);
+
+		valid = max_age_from_cache_control("max-age=0", &max_age);
+		ensure("zero max-age is valid", valid);
+
+		// *TODO: Handle "0000" as zero
+		//valid = max_age_from_cache_control("max-age=0000", &max_age);
+		//ensure("multi-zero max-age is valid", valid);
+
+		valid = max_age_from_cache_control("max-age=-123", &max_age);
+		ensure("less than zero max-age is invalid", !valid);
+	}
+}