Cluster Config Sync: Check the timestamp prior to config file checksums

Otherwise old configuration received from a secondary master/satellite
could always trigger a config change & reload.

diff --git a/lib/remote/apilistener-filesync.cpp b/lib/remote/apilistener-filesync.cpp
index f069e2623607bc90f699d0e40ac9d974d99a7841..4371a826c880702dbf1e4532ef7689f2cd0053af 100644 (file)
--- a/lib/remote/apilistener-filesync.cpp
+++ b/lib/remote/apilistener-filesync.cpp
@@ -229,6 +229,56 @@ void ApiListener::SendConfigUpdate(const JsonRpcConnection::Ptr& aclient)
        aclient->SendMessage(message);
 }
 
+static bool CompareTimestampsConfigChange(const Dictionary::Ptr& productionConfig, const Dictionary::Ptr& receivedConfig,
+       const String& stageConfigZoneDir)
+{
+       double productionTimestamp;
+       double receivedTimestamp;
+
+       // Missing production timestamp means that something really broke. Always trigger a config change then.
+       if (!productionConfig->Contains("/.timestamp"))
+               productionTimestamp = 0;
+       else
+               productionTimestamp = productionConfig->Get("/.timestamp");
+
+       // Missing received config timestamp means that something really broke. Always trigger a config change then.
+       if (!receivedConfig->Contains("/.timestamp"))
+               receivedTimestamp = Utility::GetTime() + 10;
+       else
+               receivedTimestamp = receivedConfig->Get("/.timestamp");
+
+       bool configChange;
+
+       // Skip update if our configuration files are more recent.
+       if (productionTimestamp >= receivedTimestamp) {
+
+               Log(LogInformation, "ApiListener")
+                       << "Our production configuration is more recent than the received configuration update."
+                       << " Ignoring configuration file update for path '" << stageConfigZoneDir << "'. Current timestamp '"
+                       << Utility::FormatDateTime("%Y-%m-%d %H:%M:%S %z", productionTimestamp) << "' ("
+                       << std::fixed << std::setprecision(6) << productionTimestamp
+                       << ") >= received timestamp '"
+                       << Utility::FormatDateTime("%Y-%m-%d %H:%M:%S %z", receivedTimestamp) << "' ("
+                       << receivedTimestamp << ").";
+
+               configChange = false;
+
+       } else {
+               configChange = true;
+       }
+
+       // Update the .timestamp file inside the staging directory.
+       String tsPath = stageConfigZoneDir + "/.timestamp";
+
+       if (!Utility::PathExists(tsPath)) {
+               std::ofstream fp(tsPath.CStr(), std::ofstream::out | std::ostream::trunc);
+               fp << std::fixed << receivedTimestamp;
+               fp.close();
+       }
+
+       return configChange;
+}
+
 /**
  * Registered handler when a new config::Update message is received.
  *
@@ -360,11 +410,13 @@ Value ApiListener::ConfigUpdateHandler(const MessageOrigin::Ptr& origin, const D
                if (checksums) {
                        Log(LogInformation, "ApiListener")
                                << "Received configuration for zone '" << zoneName << "' from endpoint '"
-                               << fromEndpointName << "'. Comparing the checksums.";
+                               << fromEndpointName << "'. Comparing the timestamp and checksums.";
 
-                       // TODO: Do this earlier in hello-handshakes?
-                       if (CheckConfigChange(productionConfigInfo, newConfigInfo))
-                               configChange = true;
+                       if (CompareTimestampsConfigChange(productionConfig, newConfig, stageConfigZoneDir)) {
+
+                               if (CheckConfigChange(productionConfigInfo, newConfigInfo))
+                                       configChange = true;
+                       }
 
                } else {
                        /* Fallback to timestamp handling when the parent endpoint didn't send checks.
@@ -377,33 +429,7 @@ Value ApiListener::ConfigUpdateHandler(const MessageOrigin::Ptr& origin, const D
                                << "Received configuration update without checksums from parent endpoint "
                                << fromEndpointName << ". This behaviour is deprecated. Please upgrade the parent endpoint to 2.11+";
 
-                       double productionTimestamp;
-
-                       if (!productionConfig->Contains("/.timestamp"))
-                               productionTimestamp = 0;
-                       else
-                               productionTimestamp = productionConfig->Get("/.timestamp");
-
-                       double newTimestamp;
-
-                       if (!newConfig->Contains("/.timestamp"))
-                               newTimestamp = Utility::GetTime();
-                       else
-                               newTimestamp = newConfig->Get("/.timestamp");
-
-                       // Skip update if our configuration files are more recent.
-                       if (productionTimestamp >= newTimestamp) {
-
-                               Log(LogInformation, "ApiListener")
-                                       << "Our configuration is more recent than the received configuration update."
-                                       << " Ignoring configuration file update for path '" << stageConfigZoneDir << "'. Current timestamp '"
-                                       << Utility::FormatDateTime("%Y-%m-%d %H:%M:%S %z", productionTimestamp) << "' ("
-                                       << std::fixed << std::setprecision(6) << productionTimestamp
-                                       << ") >= received timestamp '"
-                                       << Utility::FormatDateTime("%Y-%m-%d %H:%M:%S %z", newTimestamp) << "' ("
-                                       << newTimestamp << ").";
-
-                       } else {
+                       if (CompareTimestampsConfigChange(productionConfig, newConfig, stageConfigZoneDir)) {
                                configChange = true;
                        }
 
@@ -420,14 +446,6 @@ Value ApiListener::ConfigUpdateHandler(const MessageOrigin::Ptr& origin, const D
                                        }
                                }
                        }
-
-                       // Update the .timestamp file.
-                       String tsPath = stageConfigZoneDir + "/.timestamp";
-                       if (!Utility::PathExists(tsPath)) {
-                               std::ofstream fp(tsPath.CStr(), std::ofstream::out | std::ostream::trunc);
-                               fp << std::fixed << newTimestamp;
-                               fp.close();
-                       }
                }
 
                // Dump the received configuration for this zone into the stage directory.
@@ -507,7 +525,7 @@ Value ApiListener::ConfigUpdateHandler(const MessageOrigin::Ptr& origin, const D
        } else {
                Log(LogInformation, "ApiListener")
                        << "Received configuration updates (" << count << ") from endpoint '" << fromEndpointName
-                       << "' are equal to production, not triggering reload.";
+                       << "' do not qualify for production, not triggering reload.";
        }
 
        return Empty;