The TraverserEngine now honors variables in conditions properly

arangod/Aql/ExecutionEngine.cpp

@@ -838,6 +838,7 @@ struct CoordinatorInstanciator : public WalkerWorker<ExecutionNode> {
     //
     // {
     //   "options": <options.toVelocyPack>,
+    //   "variables": [<vars used in conditions>], // optional
     //   "shards": {
     //     "edges" : [
     //       [ <shards of edge collection 1> ],
@@ -854,6 +855,19 @@ struct CoordinatorInstanciator : public WalkerWorker<ExecutionNode> {
                                         query->vocbase()->_name) +
                           "/_internal/traverser");
     auto cc = arangodb::ClusterComm::instance();
+    bool hasVars = false;
+    VPackBuilder varInfo;
+    std::vector<aql::Variable const*> vars;
+    en->getConditionVariables(vars);
+    if (!vars.empty()) {
+      hasVars = true;
+      varInfo.openArray();
+      for (auto v : vars) {
+        v->toVelocyPack(varInfo);
+      }
+      varInfo.close();
+    }
+
     VPackBuilder engineInfo;
     for (auto const& list : mappingServerToCollections) {
       std::unordered_set<std::string> shardSet;
@@ -861,6 +875,10 @@ struct CoordinatorInstanciator : public WalkerWorker<ExecutionNode> {
       engineInfo.openObject();
       engineInfo.add(VPackValue("options"));
       engineInfo.add(optsBuilder.slice());
+      if (hasVars) {
+        engineInfo.add(VPackValue("variables"));
+        engineInfo.add(varInfo.slice());
+      }
 
       engineInfo.add(VPackValue("shards"));
       engineInfo.openObject();

arangod/Aql/TraversalNode.h

@@ -305,8 +305,6 @@ class TraversalNode : public ExecutionNode {
   ///        traversal
   bool _specializedNeighborsSearch;
 
-#warning THIS IS ALL NEW STUFF
-
   /// @brief Temporary pseudo variable for the currently traversed object.
   Variable const* _tmpObjVariable;
 

arangod/Cluster/TraverserEngine.cpp

@@ -24,6 +24,7 @@
 #include "TraverserEngine.h"
 
 #include "Basics/Exceptions.h"
+#include "Aql/Ast.h"
 #include "Aql/Query.h"
 #include "Utils/AqlTransaction.h"
 #include "Utils/CollectionNameResolver.h"
@@ -37,6 +38,7 @@ using namespace arangodb::traverser;
 static const std::string OPTIONS = "options";
 static const std::string SHARDS = "shards";
 static const std::string EDGES = "edges";
+static const std::string VARIABLES = "variables";
 static const std::string VERTICES = "vertices";
 
 TraverserEngine::TraverserEngine(TRI_vocbase_t* vocbase,
@@ -103,6 +105,21 @@ TraverserEngine::TraverserEngine(TRI_vocbase_t* vocbase,
   auto opts = std::make_shared<VPackBuilder>();
   _query = new aql::Query(true, vocbase, "", 0, params, opts, aql::PART_DEPENDENT);
   _query->injectTransaction(_trx);
+
+  VPackSlice variablesSlice = info.get(VARIABLES);
+  if (!variablesSlice.isNone()) {
+    if (!variablesSlice.isArray()) {
+      THROW_ARANGO_EXCEPTION_MESSAGE(
+          TRI_ERROR_BAD_PARAMETER,
+          "The optional " + VARIABLES + " has to be an array.");
+    }
+    for (auto v : VPackArrayIterator(variablesSlice)) {
+      // TODO do we have to keep the variable somewhere?
+      _query->ast()->variables()->createVariable(v);
+    }
+  }
+
+
   _trx->begin(); // We begin the transaction before we lock.
                  // We also setup indexes before we lock.
   _opts.reset(new TraverserOptions(_query, optsSlice, edgesSlice));

arangod/InternalRestHandler/InternalRestTraverserHandler.cpp

@@ -101,7 +101,6 @@ void InternalRestTraverserHandler::createEngine() {
         "Expected an object with traverser information as body parameter");
     return;
   }
-
   traverser::TraverserEngineID id = _registry->createNew(_vocbase, parsedBody->slice());
   TRI_ASSERT(id != 0);
   VPackBuilder resultBuilder;