Removed external expander functions and moved them into the PathFinder implementations.

arangod/Aql/ShortestPathBlock.cpp

@@ -44,105 +44,6 @@ using namespace arangodb::aql;
 ///        Will be handed over to the path finder
 namespace arangodb {
 namespace aql {
-struct ConstDistanceExpanderLocal {
- private:
-  /// @brief reference to the Block
-  ShortestPathBlock const* _block;
-
-  /// @brief Defines if this expander follows the edges in reverse
-  bool _isReverse;
-
- public:
-  ConstDistanceExpanderLocal(ShortestPathBlock const* block, bool isReverse)
-      : _block(block), _isReverse(isReverse) {}
-
-  void operator()(VPackSlice const& v, std::vector<VPackSlice>& resEdges,
-                  std::vector<VPackSlice>& neighbors) {
-    TRI_ASSERT(v.isString());
-    std::string id = v.copyString();
-    ManagedDocumentResult* mmdr = _block->_mmdr.get();
-    std::unique_ptr<arangodb::OperationCursor> edgeCursor;
-    for (auto const& edgeCollection : _block->_collectionInfos) {
-      TRI_ASSERT(edgeCollection != nullptr);
-      if (_isReverse) {
-        edgeCursor = edgeCollection->getReverseEdges(id, mmdr);
-      } else {
-        edgeCursor = edgeCollection->getEdges(id, mmdr);
-      }
-
-      LogicalCollection* collection = edgeCursor->collection();
-      auto cb = [&](DocumentIdentifierToken const& element) {
-        if (collection->readDocument(_block->transaction(), element, *mmdr)) {
-          VPackSlice edge(mmdr->vpack());
-          VPackSlice from = transaction::helpers::extractFromFromDocument(edge);
-          if (from == v) {
-            VPackSlice to = transaction::helpers::extractToFromDocument(edge);
-            if (to != v) {
-              resEdges.emplace_back(edge);
-              neighbors.emplace_back(to);
-            }
-          } else {
-            resEdges.emplace_back(edge);
-            neighbors.emplace_back(from);
-          }
-        }
-      };
-      while (edgeCursor->getMore(cb, 1000)) {
-      }
-    }
-  }
-};
-
-/// @brief Cluster class to expand edges.
-///        Will be handed over to the path finder
-struct ConstDistanceExpanderCluster {
- private:
-  /// @brief reference to the Block
-  ShortestPathBlock* _block;
-
-  /// @brief Defines if this expander follows the edges in reverse
-  bool _isReverse;
-
- public:
-  ConstDistanceExpanderCluster(ShortestPathBlock* block, bool isReverse)
-      : _block(block), _isReverse(isReverse) {}
-
-  void operator()(VPackSlice const& v, std::vector<VPackSlice>& resEdges,
-                  std::vector<VPackSlice>& neighbors) {
-    int res = TRI_ERROR_NO_ERROR;
-    for (auto const& edgeCollection : _block->_collectionInfos) {
-      VPackBuilder result;
-      TRI_ASSERT(edgeCollection != nullptr);
-      if (_isReverse) {
-        res = edgeCollection->getReverseEdgesCoordinator(v, result);
-      } else {
-        res = edgeCollection->getEdgesCoordinator(v, result);
-      }
-
-      if (res != TRI_ERROR_NO_ERROR) {
-        THROW_ARANGO_EXCEPTION(res);
-      }
-
-      VPackSlice edges = result.slice().get("edges");
-      for (auto const& edge : VPackArrayIterator(edges)) {
-        VPackSlice from = transaction::helpers::extractFromFromDocument(edge);
-        if (from == v) {
-          VPackSlice to = transaction::helpers::extractToFromDocument(edge);
-          if (to != v) {
-            resEdges.emplace_back(edge);
-            neighbors.emplace_back(to);
-          }
-        } else {
-          resEdges.emplace_back(edge);
-          neighbors.emplace_back(from);
-        }
-      }
-      // Make sure the data Slices are pointing to is not running out of scope.
-      // This is not thread-safe!
-      _block->_coordinatorCache.emplace_back(result.steal());
-    }
-  }
-};
 
 /// @brief Expander for weighted edges
 struct EdgeWeightExpanderLocal {
@@ -354,9 +255,8 @@ ShortestPathBlock::ShortestPathBlock(ExecutionEngine* engine,
           EdgeWeightExpanderCluster(this, false),
           EdgeWeightExpanderCluster(this, true), _opts.bidirectional));
     } else {
-      _finder.reset(new arangodb::graph::ConstantWeightShortestPathFinder(
-          ConstDistanceExpanderCluster(this, false),
-          ConstDistanceExpanderCluster(this, true)));
+      _finder.reset(
+          new arangodb::graph::ConstantWeightShortestPathFinder(this));
     }
   } else {
     if (_opts.useWeight) {
@@ -364,9 +264,8 @@ ShortestPathBlock::ShortestPathBlock(ExecutionEngine* engine,
           EdgeWeightExpanderLocal(this, false),
           EdgeWeightExpanderLocal(this, true), _opts.bidirectional));
     } else {
-      _finder.reset(new arangodb::graph::ConstantWeightShortestPathFinder(
-          ConstDistanceExpanderLocal(this, false),
-          ConstDistanceExpanderLocal(this, true)));
+      _finder.reset(
+          new arangodb::graph::ConstantWeightShortestPathFinder(this));
     }
   }
 }

arangod/Aql/ShortestPathBlock.h

@@ -33,6 +33,7 @@ class ManagedDocumentResult;
 
 namespace graph {
 class ShortestPathFinder;
+class ConstantWeightShortestPathFinder;
 }
 
 namespace traverser {
@@ -45,11 +46,12 @@ namespace aql {
 class ShortestPathNode;
 
 class ShortestPathBlock : public ExecutionBlock {
-  friend struct ConstDistanceExpanderLocal;
-  friend struct ConstDistanceExpanderCluster;
   friend struct EdgeWeightExpanderLocal;
   friend struct EdgeWeightExpanderCluster;
 
+  // TODO ONLY TEMPORARY
+  friend class graph::ConstantWeightShortestPathFinder;
+
  public:
   ShortestPathBlock(ExecutionEngine* engine, ShortestPathNode const* ep);
 

arangod/Graph/ConstantWeightShortestPathFinder.cpp

@@ -23,15 +23,24 @@
 
 #include "ConstantWeightShortestPathFinder.h"
 
-#include <velocypack/Slice.h>
+#include "Aql/ShortestPathBlock.h"
+#include "Cluster/ServerState.h"
+#include "Utils/OperationCursor.h"
+#include "VocBase/EdgeCollectionInfo.h"
+#include "VocBase/LogicalCollection.h"
+#include "VocBase/ManagedDocumentResult.h"
 #include "VocBase/Traverser.h"
 
+#include <velocypack/Iterator.h>
+#include <velocypack/Slice.h>
+#include <velocypack/velocypack-aliases.h>
+
 using namespace arangodb;
 using namespace arangodb::graph;
 
 ConstantWeightShortestPathFinder::ConstantWeightShortestPathFinder(
-    ExpanderFunction left, ExpanderFunction right)
-    : _leftNeighborExpander(left), _rightNeighborExpander(right) {}
+    arangodb::aql::ShortestPathBlock* block)
+    : _block(block) {}
 
 ConstantWeightShortestPathFinder::~ConstantWeightShortestPathFinder() {
   clearVisited();
@@ -72,7 +81,11 @@ bool ConstantWeightShortestPathFinder::shortestPath(
     nextClosure.clear();
     if (_leftClosure.size() < _rightClosure.size()) {
       for (arangodb::velocypack::Slice& v : _leftClosure) {
-        _leftNeighborExpander(v, edges, neighbors);
+        if (arangodb::ServerState::instance()->isCoordinator()) {
+          expandVertexCluster(false, v, edges, neighbors);
+        } else {
+          expandVertex(false, v, edges, neighbors);
+        }
         size_t const neighborsSize = neighbors.size();
         TRI_ASSERT(edges.size() == neighborsSize);
         for (size_t i = 0; i < neighborsSize; ++i) {
@@ -112,7 +125,11 @@ bool ConstantWeightShortestPathFinder::shortestPath(
       nextClosure.clear();
     } else {
       for (arangodb::velocypack::Slice& v : _rightClosure) {
-        _rightNeighborExpander(v, edges, neighbors);
+        if (arangodb::ServerState::instance()->isCoordinator()) {
+          expandVertexCluster(true, v, edges, neighbors);
+        } else {
+          expandVertex(true, v, edges, neighbors);
+        }
         size_t const neighborsSize = neighbors.size();
         TRI_ASSERT(edges.size() == neighborsSize);
         for (size_t i = 0; i < neighborsSize; ++i) {
@@ -155,6 +172,80 @@ bool ConstantWeightShortestPathFinder::shortestPath(
   return false;
 }
 
+void ConstantWeightShortestPathFinder::expandVertex(
+    bool backward, VPackSlice& vertex, std::vector<VPackSlice>& edges,
+    std::vector<VPackSlice>& neighbors) {
+  TRI_ASSERT(vertex.isString());
+  std::string id = vertex.copyString();
+  ManagedDocumentResult* mmdr = _block->_mmdr.get();
+  std::unique_ptr<arangodb::OperationCursor> edgeCursor;
+  for (auto const& edgeCollection : _block->_collectionInfos) {
+    TRI_ASSERT(edgeCollection != nullptr);
+    if (backward) {
+      edgeCursor = edgeCollection->getReverseEdges(id, mmdr);
+    } else {
+      edgeCursor = edgeCollection->getEdges(id, mmdr);
+    }
+
+    LogicalCollection* collection = edgeCursor->collection();
+    auto cb = [&](DocumentIdentifierToken const& element) {
+      if (collection->readDocument(_block->transaction(), element, *mmdr)) {
+        VPackSlice edge(mmdr->vpack());
+        VPackSlice from = transaction::helpers::extractFromFromDocument(edge);
+        if (from == vertex) {
+          VPackSlice to = transaction::helpers::extractToFromDocument(edge);
+          if (to != vertex) {
+            edges.emplace_back(edge);
+            neighbors.emplace_back(to);
+          }
+        } else {
+          edges.emplace_back(edge);
+          neighbors.emplace_back(from);
+        }
+      }
+    };
+    while (edgeCursor->getMore(cb, 1000)) {
+    }
+  }
+}
+
+void ConstantWeightShortestPathFinder::expandVertexCluster(
+    bool backward, VPackSlice& vertex, std::vector<VPackSlice>& resEdges,
+    std::vector<VPackSlice>& neighbors) {
+  int res = TRI_ERROR_NO_ERROR;
+  for (auto const& edgeCollection : _block->_collectionInfos) {
+    VPackBuilder result;
+    TRI_ASSERT(edgeCollection != nullptr);
+    if (backward) {
+      res = edgeCollection->getReverseEdgesCoordinator(vertex, result);
+    } else {
+      res = edgeCollection->getEdgesCoordinator(vertex, result);
+    }
+
+    if (res != TRI_ERROR_NO_ERROR) {
+      THROW_ARANGO_EXCEPTION(res);
+    }
+
+    VPackSlice edges = result.slice().get("edges");
+    for (auto const& edge : VPackArrayIterator(edges)) {
+      VPackSlice from = transaction::helpers::extractFromFromDocument(edge);
+      if (from == vertex) {
+        VPackSlice to = transaction::helpers::extractToFromDocument(edge);
+        if (to != vertex) {
+          resEdges.emplace_back(edge);
+          neighbors.emplace_back(to);
+        }
+      } else {
+        resEdges.emplace_back(edge);
+        neighbors.emplace_back(from);
+      }
+    }
+    // Make sure the data Slices are pointing to is not running out of scope.
+    // This is not thread-safe!
+    _block->_coordinatorCache.emplace_back(result.steal());
+  }
+}
+
 void ConstantWeightShortestPathFinder::clearVisited() {
   for (auto& it : _leftFound) {
     delete it.second;

arangod/Graph/ConstantWeightShortestPathFinder.h

@@ -28,6 +28,11 @@
 #include "Graph/ShortestPathFinder.h"
 
 namespace arangodb {
+
+namespace aql {
+class ShortestPathBlock;
+}
+
 namespace velocypack {
 class Slice;
 }
@@ -68,12 +73,11 @@ class ConstantWeightShortestPathFinder : public ShortestPathFinder {
       _rightFound;
   std::deque<arangodb::velocypack::Slice> _rightClosure;
 
-  ExpanderFunction _leftNeighborExpander;
-  ExpanderFunction _rightNeighborExpander;
+  // TODO Remove Me!
+  arangodb::aql::ShortestPathBlock* _block;
 
  public:
-  ConstantWeightShortestPathFinder(ExpanderFunction left,
-                                   ExpanderFunction right);
+  ConstantWeightShortestPathFinder(arangodb::aql::ShortestPathBlock* block);
 
   ~ConstantWeightShortestPathFinder();
 
@@ -83,6 +87,14 @@ class ConstantWeightShortestPathFinder : public ShortestPathFinder {
                     std::function<void()> const& callback) override;
 
  private:
+  void expandVertex(bool backward, arangodb::velocypack::Slice& vertex,
+                    std::vector<arangodb::velocypack::Slice>& edges,
+                    std::vector<arangodb::velocypack::Slice>& neighbors);
+
+  void expandVertexCluster(bool backward, arangodb::velocypack::Slice& vertex,
+                           std::vector<arangodb::velocypack::Slice>& edges,
+                           std::vector<arangodb::velocypack::Slice>& neighbors);
+
   void clearVisited();
 };