Support for selective synchronization as a startup flag

BedrockServer.cpp

@@ -6,6 +6,7 @@
 #include <sys/resource.h>
 #include <sys/time.h>
 #include <signal.h>
+#include <string.h>
 
 #include <bedrockVersion.h>
 #include <BedrockCore.h>
@@ -1338,6 +1339,20 @@ BedrockServer::BedrockServer(const SData& args_)
                      ref(_leaderVersion),
                      ref(_syncNodeQueuedCommands),
                      ref(*this));
+
+    // Add syncType arg. If no -syncType specified, default to QUORUM
+    _isSyncSet = args.isSet("-syncType");
+    _syncType = -1;
+    if (_isSyncSet) {
+        string cmd = args["-syncType"];
+        if ( strcasecmp(cmd.c_str(),SC_ONE) == 0) {
+            _syncType = SQLiteNode::ONE;
+        } else if (strcasecmp(cmd.c_str(),SC_ASYNC) == 0) {
+            _syncType = SQLiteNode::ASYNC;
+        } else if (strcasecmp(cmd.c_str(),SC_QUORUM) == 0) {
+            _syncType = SQLiteNode::QUORUM;
+        }
+    }
 }
 
 BedrockServer::~BedrockServer() {
@@ -1606,6 +1621,15 @@ void BedrockServer::postPoll(fd_map& fdm, uint64_t& nextActivity) {
                     // Create a command.
                     unique_ptr<BedrockCommand> command = getCommandFromPlugins(move(request));
 
+                    // Check if -syncType is set and query starts with INSERT/DELETE/UPDATE
+                    if (_isSyncSet && command->request.methodLine.compare("QUERY")) {
+                        string query = STrim(SToUpper(command->request["query"]));
+                        if (SStartsWith(SToUpper(query),"INSERT") || SStartsWith(SToUpper(query),"DELETE") || SStartsWith(SToUpper(query),"UPDATE")) {
+                            command->writeConsistency = (SQLiteNode::ConsistencyLevel)_syncType;
+                            SINFO("Forcing " << _syncType << " consistency for command " << command->request.methodLine);
+                        }
+                    }
+
                     if (command->writeConsistency != SQLiteNode::QUORUM
                         && _syncCommands.find(command->request.methodLine) != _syncCommands.end()) {
 

BedrockServer.h

@@ -6,6 +6,10 @@
 #include "BedrockCommandQueue.h"
 #include "BedrockTimeoutCommandQueue.h"
 
+#define SC_ONE "ONE"
+#define SC_QUORUM "QUORUM"
+#define SC_ASYNC "ASYNC"
+
 class BedrockServer : public SQLiteServer {
   public:
 
@@ -483,4 +487,8 @@ class BedrockServer : public SQLiteServer {
     // This is a snapshot of the state of the node taken at the beginning of any call to peekCommand or processCommand
     // so that the state can't change for the lifetime of that call, from the view of that function.
     static thread_local atomic<SQLiteNode::State> _nodeStateSnapshot;
+
+    // These allow for the ability to startup with -syncType while specifying ONE/ASYNC/QUORUM
+    bool _isSyncSet;
+    int _syncType;
 };

docs/cli.md

@@ -30,6 +30,8 @@ To see a full list of Bedrock's configuration options, just run `bedrock -?` on
 	-readThreads    <#>         Number of read threads to start (min 1, defaults to 1)
 	-queryLog       <filename>  Set the query log filename (default 'queryLog.csv', SIGUSR2/SIGQUIT to enable/disable)
 	-maxJournalSize <#commits>  Number of commits to retainin the historical journal (default 1000000)
+    -syncType       <value>     Selective synchronization (QUORUM, ONE, ASYNC) and (defaults to QUORUM)
+    -synchronous    <value>     Set the PRAGMA schema.synchronous
 
 	Quick Start Tips:
 	-----------------

main.cpp

@@ -239,6 +239,7 @@ int main(int argc, char* argv[]) {
              << endl;
         cout << "-maxJournalSize <#commits>  Number of commits to retain in the historical journal (default 1000000)"
              << endl;
+        cout << "-syncType       <value>     Selective synchronization (QUORUM, ONE, ASYNC) and (defaults to QUORUM) " << endl;
         cout << "-synchronous    <value>     Set the PRAGMA schema.synchronous "
                 "(defaults see https://sqlite.org/pragma.html#pragma_synchronous)"
              << endl;