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arangodb/arangod/V8Server/V8Traverser.cpp

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////////////////////////////////////////////////////////////////////////////////
/// DISCLAIMER
///
/// Copyright 2014-2016 ArangoDB GmbH, Cologne, Germany
/// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
/// http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///
/// Copyright holder is ArangoDB GmbH, Cologne, Germany
///
/// @author Michael Hackstein
////////////////////////////////////////////////////////////////////////////////
#include "V8Traverser.h"
#include "Indexes/EdgeIndex.h"
#include "Utils/CollectionNameResolver.h"
#include "Utils/OperationCursor.h"
#include "Utils/SingleCollectionTransaction.h"
#include "VocBase/document-collection.h"
#include <velocypack/Iterator.h>
#include <velocypack/velocypack-aliases.h>
using namespace arangodb;
using namespace arangodb::basics;
using namespace arangodb::traverser;
////////////////////////////////////////////////////////////////////////////////
/// @brief Get a document by it's ID. Also lazy locks the collection.
/// If DOCUMENT_NOT_FOUND this function will return normally
/// with a OperationResult.failed() == true.
/// On all other cases this function throws.
////////////////////////////////////////////////////////////////////////////////
static OperationResult FetchDocumentById(arangodb::Transaction* trx,
std::string const& id,
VPackBuilder& builder,
OperationOptions& options) {
std::vector<std::string> parts =
arangodb::basics::StringUtils::split(id, "/");
TRI_ASSERT(parts.size() == 2);
trx->addCollectionAtRuntime(parts[0]);
builder.clear();
builder.openObject();
builder.add(VPackValue(TRI_VOC_ATTRIBUTE_KEY));
builder.add(VPackValue(parts[1]));
builder.close();
OperationResult opRes = trx->document(parts[0], builder.slice(), options);
if (opRes.failed() && opRes.code != TRI_ERROR_ARANGO_DOCUMENT_NOT_FOUND) {
THROW_ARANGO_EXCEPTION(opRes.code);
}
return opRes;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief Local class to expand edges.
/// Will be handed over to the path finder
////////////////////////////////////////////////////////////////////////////////
struct BasicExpander {
private:
std::vector<EdgeCollectionInfo*> const _colls;
arangodb::Transaction* _trx;
TRI_edge_direction_e _dir;
std::shared_ptr<OperationResult> _opRes;
public:
BasicExpander(std::vector<EdgeCollectionInfo*> const& colls,
arangodb::Transaction* trx, TRI_edge_direction_e dir)
: _colls(colls),
_trx(trx),
_dir(dir),
_opRes(std::make_shared<OperationResult>(TRI_ERROR_NO_ERROR)){};
void operator()(std::string const& v, std::vector<std::string>& res_edges,
std::vector<std::string>& neighbors) {
for (auto const& edgeCollection : _colls) {
TRI_ASSERT(edgeCollection != nullptr);
std::shared_ptr<OperationCursor> edgeCursor = edgeCollection->getEdges(_dir, v);
while (edgeCursor->hasMore()) {
edgeCursor->getMore(_opRes, UINT64_MAX, false);
if (_opRes->failed()) {
THROW_ARANGO_EXCEPTION(_opRes->code);
}
VPackSlice edges = _opRes->slice();
for (auto const& edge : VPackArrayIterator(edges)) {
std::string edgeId = _trx->extractIdString(edge);
std::string from = edge.get(TRI_VOC_ATTRIBUTE_FROM).copyString();
if (from == v) {
std::string to = edge.get(TRI_VOC_ATTRIBUTE_TO).copyString();
if (to != v) {
res_edges.emplace_back(std::move(edgeId));
neighbors.emplace_back(std::move(to));
}
} else {
res_edges.emplace_back(std::move(edgeId));
neighbors.emplace_back(std::move(from));
}
}
}
}
}
};
EdgeCollectionInfo::EdgeCollectionInfo(arangodb::Transaction* trx,
std::string const& collectionName,
WeightCalculatorFunction weighter)
: _trx(trx), _collectionName(collectionName), _weighter(weighter) {
trx->addCollectionAtRuntime(collectionName);
if (!trx->isEdgeCollection(collectionName)) {
THROW_ARANGO_EXCEPTION(TRI_ERROR_ARANGO_COLLECTION_TYPE_INVALID);
}
_indexId = trx->edgeIndexHandle(collectionName);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief Get edges for the given direction and start vertex.
////////////////////////////////////////////////////////////////////////////////
std::shared_ptr<OperationCursor> EdgeCollectionInfo::getEdges(
TRI_edge_direction_e direction, std::string const& vertexId) {
_searchBuilder.clear();
EdgeIndex::buildSearchValue(direction, vertexId, _searchBuilder);
return _trx->indexScan(_collectionName,
arangodb::Transaction::CursorType::INDEX, _indexId,
_searchBuilder.slice(), 0, UINT64_MAX, 1000, false);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief Compute the weight of an edge
////////////////////////////////////////////////////////////////////////////////
double EdgeCollectionInfo::weightEdge(VPackSlice const edge) {
return _weighter(edge);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief Return name of the wrapped collection
////////////////////////////////////////////////////////////////////////////////
std::string const& EdgeCollectionInfo::getName() {
return _collectionName;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief Expander for Multiple edge collections
////////////////////////////////////////////////////////////////////////////////
class MultiCollectionEdgeExpander {
//////////////////////////////////////////////////////////////////////////////
/// @brief Edge direction for this expander
//////////////////////////////////////////////////////////////////////////////
TRI_edge_direction_e _direction;
//////////////////////////////////////////////////////////////////////////////
/// @brief all info required for edge collection
//////////////////////////////////////////////////////////////////////////////
std::vector<EdgeCollectionInfo*> _edgeCollections;
//////////////////////////////////////////////////////////////////////////////
/// @brief function to check if the edge passes the filter
//////////////////////////////////////////////////////////////////////////////
std::function<bool(VPackSlice)> _isAllowed;
//////////////////////////////////////////////////////////////////////////////
/// @brief function to check if the vertex passes the filter
//////////////////////////////////////////////////////////////////////////////
std::function<bool(std::string const&)> _isAllowedVertex;
public:
MultiCollectionEdgeExpander(
TRI_edge_direction_e const& direction,
std::vector<EdgeCollectionInfo*> const& edgeCollections,
std::function<bool(VPackSlice const)> isAllowed,
std::function<bool(std::string const&)> isAllowedVertex)
: _direction(direction),
_edgeCollections(edgeCollections),
_isAllowed(isAllowed),
_isAllowedVertex(isAllowedVertex) {}
void operator()(std::string const& source,
std::vector<ArangoDBPathFinder::Step*>& result) {
for (auto const& edgeCollection : _edgeCollections) {
TRI_ASSERT(edgeCollection != nullptr);
auto edgeCursor = edgeCollection->getEdges(_direction, source);
std::unordered_map<std::string, size_t> candidates;
auto inserter = [&](std::string const& s, std::string const& t,
double currentWeight, VPackSlice edge) {
if (_isAllowedVertex(t)) {
auto cand = candidates.find(t);
if (cand == candidates.end()) {
// Add weight
auto step = std::make_unique<ArangoDBPathFinder::Step>(
t, s, currentWeight, edgeCollection->trx()->extractIdString(edge));
result.emplace_back(step.release());
candidates.emplace(t, result.size() - 1);
} else {
// Compare weight
auto oldWeight = result[cand->second]->weight();
if (currentWeight < oldWeight) {
result[cand->second]->setWeight(currentWeight);
}
}
}
};
auto opRes = std::make_shared<OperationResult>(TRI_ERROR_NO_ERROR);
while (edgeCursor->hasMore()) {
edgeCursor->getMore(opRes, UINT64_MAX, false);
if (opRes->failed()) {
THROW_ARANGO_EXCEPTION(opRes->code);
}
VPackSlice edges = opRes->slice();
for (auto const& edge : VPackArrayIterator(edges)) {
if (!_isAllowed(edge)) {
continue;
}
std::string const from = edge.get(TRI_VOC_ATTRIBUTE_FROM).copyString();
std::string const to = edge.get(TRI_VOC_ATTRIBUTE_TO).copyString();
double currentWeight = edgeCollection->weightEdge(edge);
if (from == source) {
inserter(from, to, currentWeight, edge);
} else {
inserter(to, from, currentWeight, edge);
}
}
}
}
}
};
class SimpleEdgeExpander {
//////////////////////////////////////////////////////////////////////////////
/// @brief The direction used for edges in this expander
//////////////////////////////////////////////////////////////////////////////
TRI_edge_direction_e _direction;
//////////////////////////////////////////////////////////////////////////////
/// @brief all info required for edge collection
//////////////////////////////////////////////////////////////////////////////
EdgeCollectionInfo* _edgeCollection;
std::unordered_map<std::string, size_t> _candidates;
public:
SimpleEdgeExpander(TRI_edge_direction_e& direction,
EdgeCollectionInfo* edgeCollection)
: _direction(direction), _edgeCollection(edgeCollection) {}
void operator()(std::string const& source,
std::vector<ArangoDBPathFinder::Step*>& result) {
TRI_ASSERT(_edgeCollection != nullptr);
_candidates.clear();
auto inserter = [&](std::string const& s, std::string const& t,
double currentWeight, VPackSlice edge) {
auto cand = _candidates.find(t);
if (cand == _candidates.end()) {
// Add weight
auto step = std::make_unique<ArangoDBPathFinder::Step>(
std::move(t), std::move(s), currentWeight, _edgeCollection->trx()->extractIdString(edge));
result.emplace_back(step.release());
} else {
// Compare weight
auto oldWeight = result[cand->second]->weight();
if (currentWeight < oldWeight) {
result[cand->second]->setWeight(currentWeight);
}
}
};
auto edgeCursor = _edgeCollection->getEdges(_direction, source);
auto opRes = std::make_shared<OperationResult>(TRI_ERROR_NO_ERROR);
while (edgeCursor->hasMore()) {
edgeCursor->getMore(opRes, UINT64_MAX, false);
if (opRes->failed()) {
THROW_ARANGO_EXCEPTION(opRes->code);
}
VPackSlice edges = opRes->slice();
for (auto const& edge : VPackArrayIterator(edges)) {
std::string const from = edge.get(TRI_VOC_ATTRIBUTE_FROM).copyString();
std::string const to = edge.get(TRI_VOC_ATTRIBUTE_TO).copyString();
double currentWeight = _edgeCollection->weightEdge(edge);
if (from == source) {
inserter(std::move(from), std::move(to), currentWeight, edge);
} else {
inserter(std::move(to), std::move(from), currentWeight, edge);
}
}
}
}
};
////////////////////////////////////////////////////////////////////////////////
/// @brief Insert a new vertex matcher object
////////////////////////////////////////////////////////////////////////////////
void BasicOptions::addVertexFilter(v8::Isolate* isolate,
v8::Handle<v8::Value> const& example,
arangodb::Transaction* trx,
std::string const& name,
std::string& errorMessage) {
auto it = _vertexFilter.find(name);
if (it == _vertexFilter.end()) {
if (example->IsArray()) {
auto matcher = std::make_unique<ExampleMatcher>(
isolate, v8::Handle<v8::Array>::Cast(example), errorMessage);
_vertexFilter.emplace(name, matcher.release());
} else {
// Has to be Object
auto matcher = std::make_unique<ExampleMatcher>(
isolate, v8::Handle<v8::Object>::Cast(example), errorMessage);
_vertexFilter.emplace(name, matcher.release());
}
}
}
////////////////////////////////////////////////////////////////////////////////
/// @brief Checks if a vertex matches to given examples
////////////////////////////////////////////////////////////////////////////////
bool BasicOptions::matchesVertex(std::string const& collectionName,
std::string const& key,
VPackSlice vertex) const {
if (!useVertexFilter) {
// Nothing to do
return true;
}
auto it = _vertexFilter.find(collectionName);
if (it == _vertexFilter.end()) {
// This collection does not have any object of this shape.
// Short circuit.
return false;
}
return it->second->matches(vertex);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief Insert a new edge matcher object
////////////////////////////////////////////////////////////////////////////////
void BasicOptions::addEdgeFilter(v8::Isolate* isolate,
v8::Handle<v8::Value> const& example,
std::string const& cName,
std::string& errorMessage) {
useEdgeFilter = true;
auto it = _edgeFilter.find(cName);
if (it != _edgeFilter.end()) {
return;
}
if (example->IsArray()) {
auto matcher = std::make_unique<ExampleMatcher>(
isolate, v8::Handle<v8::Array>::Cast(example), errorMessage);
_edgeFilter.emplace(cName, matcher.release());
} else {
// Has to be Object
auto matcher = std::make_unique<ExampleMatcher>(
isolate, v8::Handle<v8::Object>::Cast(example), errorMessage);
_edgeFilter.emplace(cName, matcher.release());
}
}
////////////////////////////////////////////////////////////////////////////////
/// @brief Insert a new edge matcher object
////////////////////////////////////////////////////////////////////////////////
void BasicOptions::addEdgeFilter(VPackSlice const& example,
std::string const& cName) {
useEdgeFilter = true;
auto it = _edgeFilter.find(cName);
if (it == _edgeFilter.end()) {
auto matcher = std::make_unique<ExampleMatcher>(example, true);
_edgeFilter.emplace(cName, matcher.release());
}
}
////////////////////////////////////////////////////////////////////////////////
/// @brief Checks if an edge matches to given examples
////////////////////////////////////////////////////////////////////////////////
bool BasicOptions::matchesEdge(VPackSlice edge) const {
if (!useEdgeFilter) {
// Nothing to do
return true;
}
auto id = _trx->extractIdString(edge);
std::vector<std::string> parts = arangodb::basics::StringUtils::split(id, "/");
TRI_ASSERT(parts.size() == 2); // We have a real ID
auto it = _edgeFilter.find(parts[0]);
if (it == _edgeFilter.end()) {
// This collection does not have any object that can match.
// Short circuit.
return false;
}
return it->second->matches(edge);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief Checks if a vertex matches to given examples
////////////////////////////////////////////////////////////////////////////////
bool ShortestPathOptions::matchesVertex(std::string const& collectionName,
std::string const& key,
VPackSlice vertex) const {
std::string v = collectionName + "/" + key;
if (start == v || end == v) {
return true;
}
return BasicOptions::matchesVertex(collectionName, key, vertex);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief Checks if a vertex matches to given examples
////////////////////////////////////////////////////////////////////////////////
bool NeighborsOptions::matchesVertex(std::string const& collectionName,
std::string const& key,
VPackSlice vertex) const {
// If there are explicitly marked collections check them.
if (!_explicitCollections.empty()) {
// If the current collection is not stored the result is invalid
if (_explicitCollections.find(collectionName) == _explicitCollections.end()) {
return false;
}
}
return BasicOptions::matchesVertex(collectionName, key, vertex);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief Checks if a vertex matches to given examples. Also fetches the vertex.
////////////////////////////////////////////////////////////////////////////////
bool NeighborsOptions::matchesVertex(std::string const& id) const {
std::vector<std::string> parts =
arangodb::basics::StringUtils::split(id, "/");
TRI_ASSERT(parts.size() == 2);
// If there are explicitly marked collections check them.
if (!_explicitCollections.empty()) {
// If the current collection is not stored the result is invalid
if (_explicitCollections.find(parts[0]) == _explicitCollections.end()) {
return false;
}
}
VPackBuilder tmp;
tmp.openObject();
tmp.add(TRI_VOC_ATTRIBUTE_KEY, VPackValue(parts[1]));
tmp.close();
OperationOptions opOpts;
OperationResult opRes = _trx->document(parts[0], tmp.slice(), opOpts);
if (opRes.failed()) {
return false;
}
return BasicOptions::matchesVertex(parts[0], parts[1], opRes.slice());
}
////////////////////////////////////////////////////////////////////////////////
/// @brief Inserts one explicitly allowed collection. As soon as one is
/// explicitly
/// allowed all others are implicitly disallowed. If there is no explicitly
/// allowed
/// collection all are implicitly allowed.
////////////////////////////////////////////////////////////////////////////////
void NeighborsOptions::addCollectionRestriction(std::string const& collectionName) {
_explicitCollections.emplace(collectionName);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief Wrapper for the shortest path computation
////////////////////////////////////////////////////////////////////////////////
std::unique_ptr<ArangoDBPathFinder::Path> TRI_RunShortestPathSearch(
std::vector<EdgeCollectionInfo*> const& collectionInfos,
ShortestPathOptions& opts) {
TRI_edge_direction_e forward;
TRI_edge_direction_e backward;
if (opts.direction == "outbound") {
forward = TRI_EDGE_OUT;
backward = TRI_EDGE_IN;
} else if (opts.direction == "inbound") {
forward = TRI_EDGE_IN;
backward = TRI_EDGE_OUT;
} else {
forward = TRI_EDGE_ANY;
backward = TRI_EDGE_ANY;
}
auto edgeFilterClosure = [&opts](VPackSlice edge)
-> bool { return opts.matchesEdge(edge); };
auto vertexFilterClosure =
[&opts](std::string const& v) -> bool {
// TODO: this closure needs to be optimized
std::vector<std::string> parts = arangodb::basics::StringUtils::split(v, "/");
VPackBuilder tmp;
tmp.openObject();
tmp.add(TRI_VOC_ATTRIBUTE_KEY, VPackValue(parts[1]));
tmp.close();
OperationOptions opOpts;
OperationResult opRes = opts.trx()->document(parts[0], tmp.slice(), opOpts);
if (opRes.failed()) {
return false;
}
return opts.matchesVertex(parts[0], parts[1], opRes.slice());
};
MultiCollectionEdgeExpander forwardExpander(
forward, collectionInfos, edgeFilterClosure, vertexFilterClosure);
MultiCollectionEdgeExpander backwardExpander(
backward, collectionInfos, edgeFilterClosure, vertexFilterClosure);
ArangoDBPathFinder pathFinder(forwardExpander, backwardExpander,
opts.bidirectional);
std::unique_ptr<ArangoDBPathFinder::Path> path;
// New trx api is not thread safe. Two threads only give little performance
// gain. Maybe reactivate this in the future (MVCC).
opts.multiThreaded = false;
if (opts.multiThreaded) {
path.reset(pathFinder.shortestPathTwoThreads(opts.start, opts.end));
} else {
path.reset(pathFinder.shortestPath(opts.start, opts.end));
}
return path;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief Wrapper for the shortest path computation
////////////////////////////////////////////////////////////////////////////////
std::unique_ptr<ArangoDBConstDistancePathFinder::Path>
TRI_RunSimpleShortestPathSearch(
std::vector<EdgeCollectionInfo*> const& collectionInfos,
arangodb::Transaction* trx,
ShortestPathOptions& opts) {
TRI_edge_direction_e forward;
TRI_edge_direction_e backward;
if (opts.direction == "outbound") {
forward = TRI_EDGE_OUT;
backward = TRI_EDGE_IN;
} else if (opts.direction == "inbound") {
forward = TRI_EDGE_IN;
backward = TRI_EDGE_OUT;
} else {
forward = TRI_EDGE_ANY;
backward = TRI_EDGE_ANY;
}
auto fwExpander = BasicExpander(collectionInfos, trx, forward);
auto bwExpander = BasicExpander(collectionInfos, trx, backward);
ArangoDBConstDistancePathFinder pathFinder(fwExpander, bwExpander);
auto path = std::unique_ptr<ArangoDBConstDistancePathFinder::Path>(
pathFinder.search(opts.start, opts.end));
return path;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief search for distinct inbound neighbors
////////////////////////////////////////////////////////////////////////////////
static void InboundNeighbors(std::vector<EdgeCollectionInfo*>& collectionInfos,
NeighborsOptions& opts,
std::unordered_set<std::string>& startVertices,
std::unordered_set<std::string>& visited,
std::unordered_set<std::string>& distinct,
uint64_t depth = 1) {
TRI_edge_direction_e dir = TRI_EDGE_IN;
std::unordered_set<std::string> nextDepth;
auto opRes = std::make_shared<OperationResult>(TRI_ERROR_NO_ERROR);
for (auto const& col : collectionInfos) {
TRI_ASSERT(col != nullptr);
for (auto const& start : startVertices) {
auto edgeCursor = col->getEdges(dir, start);
while (edgeCursor->hasMore()) {
edgeCursor->getMore(opRes, UINT64_MAX, false);
if (opRes->failed()) {
THROW_ARANGO_EXCEPTION(opRes->code);
}
VPackSlice edges = opRes->slice();
for (auto const& edge : VPackArrayIterator(edges)) {
if (opts.matchesEdge(edge)) {
std::string v = edge.get(TRI_VOC_ATTRIBUTE_FROM).copyString();
if (visited.find(v) != visited.end()) {
// We have already visited this vertex
continue;
}
visited.emplace(v);
if (depth >= opts.minDepth) {
if (opts.matchesVertex(v)) {
distinct.emplace(v);
}
}
if (depth < opts.maxDepth) {
nextDepth.emplace(v);
}
}
}
}
}
}
if (!nextDepth.empty()) {
InboundNeighbors(collectionInfos, opts, nextDepth, visited, distinct,
depth + 1);
}
}
////////////////////////////////////////////////////////////////////////////////
/// @brief search for distinct outbound neighbors
////////////////////////////////////////////////////////////////////////////////
static void OutboundNeighbors(std::vector<EdgeCollectionInfo*>& collectionInfos,
NeighborsOptions& opts,
std::unordered_set<std::string> const& startVertices,
std::unordered_set<std::string>& visited,
std::unordered_set<std::string>& distinct,
uint64_t depth = 1) {
TRI_edge_direction_e dir = TRI_EDGE_OUT;
std::unordered_set<std::string> nextDepth;
auto opRes = std::make_shared<OperationResult>(TRI_ERROR_NO_ERROR);
for (auto const& col : collectionInfos) {
TRI_ASSERT(col != nullptr);
for (auto const& start : startVertices) {
auto edgeCursor = col->getEdges(dir, start);
while (edgeCursor->hasMore()) {
edgeCursor->getMore(opRes, UINT64_MAX, false);
if (opRes->failed()) {
THROW_ARANGO_EXCEPTION(opRes->code);
}
VPackSlice edges = opRes->slice();
for (auto const& edge : VPackArrayIterator(edges)) {
if (opts.matchesEdge(edge)) {
VPackValueLength l;
char const* v = edge.get(TRI_VOC_ATTRIBUTE_TO).getString(l);
if (visited.find(std::string(v, l)) != visited.end()) {
// We have already visited this vertex
continue;
}
std::string tmp(v, l);
if (depth >= opts.minDepth) {
if (opts.matchesVertex(tmp)) {
distinct.emplace(tmp);
}
}
if (depth < opts.maxDepth) {
nextDepth.emplace(tmp);
}
visited.emplace(std::move(tmp));
}
}
}
}
}
if (!nextDepth.empty()) {
OutboundNeighbors(collectionInfos, opts, nextDepth, visited, distinct,
depth + 1);
}
}
////////////////////////////////////////////////////////////////////////////////
/// @brief search for distinct in- and outbound neighbors
////////////////////////////////////////////////////////////////////////////////
static void AnyNeighbors(std::vector<EdgeCollectionInfo*>& collectionInfos,
NeighborsOptions& opts,
std::unordered_set<std::string>& startVertices,
std::unordered_set<std::string>& visited,
std::unordered_set<std::string>& distinct,
uint64_t depth = 1) {
TRI_edge_direction_e dir = TRI_EDGE_ANY;
std::unordered_set<std::string> nextDepth;
auto opRes = std::make_shared<OperationResult>(TRI_ERROR_NO_ERROR);
for (auto const& col : collectionInfos) {
TRI_ASSERT(col != nullptr);
for (auto const& start : startVertices) {
auto edgeCursor = col->getEdges(dir, start);
while (edgeCursor->hasMore()) {
edgeCursor->getMore(opRes, UINT64_MAX, false);
if (opRes->failed()) {
THROW_ARANGO_EXCEPTION(opRes->code);
}
VPackSlice edges = opRes->slice();
for (auto const& edge : VPackArrayIterator(edges)) {
if (opts.matchesEdge(edge)) {
std::string v = edge.get(TRI_VOC_ATTRIBUTE_TO).copyString();
if (visited.find(v) == visited.end()) {
visited.emplace(v);
if (depth >= opts.minDepth) {
if (opts.matchesVertex(v)) {
distinct.emplace(v);
}
}
if (depth < opts.maxDepth) {
nextDepth.emplace(v);
}
}
v = edge.get(TRI_VOC_ATTRIBUTE_FROM).copyString();
if (visited.find(v) == visited.end()) {
visited.emplace(v);
if (depth >= opts.minDepth) {
if (opts.matchesVertex(v)) {
distinct.emplace(v);
}
}
if (depth < opts.maxDepth) {
nextDepth.emplace(v);
}
}
}
}
}
}
}
if (!nextDepth.empty()) {
AnyNeighbors(collectionInfos, opts, nextDepth, visited, distinct,
depth + 1);
}
}
////////////////////////////////////////////////////////////////////////////////
/// @brief Execute a search for neighboring vertices
////////////////////////////////////////////////////////////////////////////////
void TRI_RunNeighborsSearch(std::vector<EdgeCollectionInfo*>& collectionInfos,
NeighborsOptions& opts,
std::unordered_set<std::string>& result) {
std::unordered_set<std::string> startVertices;
std::unordered_set<std::string> visited;
startVertices.emplace(opts.start);
visited.emplace(opts.start);
switch (opts.direction) {
case TRI_EDGE_IN:
InboundNeighbors(collectionInfos, opts, startVertices, visited, result);
break;
case TRI_EDGE_OUT:
OutboundNeighbors(collectionInfos, opts, startVertices, visited, result);
break;
case TRI_EDGE_ANY:
AnyNeighbors(collectionInfos, opts, startVertices, visited, result);
break;
}
}
void SingleServerTraversalPath::getDocumentByIdentifier(Transaction* trx,
std::string const& identifier,
VPackBuilder& result) {
// TODO Check if we can get away with using ONLY VPackSlices referencing externals instead of std::string.
// I am afaid that they may run out of scope.
OperationOptions options;
OperationResult opRes = FetchDocumentById(trx, identifier, _searchBuilder, options);
if (opRes.failed()) {
THROW_ARANGO_EXCEPTION(opRes.code);
}
result.add(opRes.slice());
}
void SingleServerTraversalPath::pathToVelocyPack(Transaction* trx,
VPackBuilder& result) {
result.openObject();
result.add(VPackValue("edges"));
result.openArray();
for (auto const& it : _path.edges) {
auto cached = _traverser->_edges.find(it);
// All edges are cached!!
TRI_ASSERT(cached != _traverser->_edges.end());
result.add(VPackSlice(cached->second->data()));
}
result.close();
result.add(VPackValue("vertices"));
result.openArray();
for (auto const& it : _path.vertices) {
std::shared_ptr<VPackBuffer<uint8_t>> vertex =
_traverser->fetchVertexData(it);
result.add(VPackSlice(vertex->data()));
}
result.close();
result.close();
}
void SingleServerTraversalPath::lastEdgeToVelocyPack(Transaction* trx, VPackBuilder& result) {
auto cached = _traverser->_edges.find(_path.edges.back());
// All edges are cached!!
TRI_ASSERT(cached != _traverser->_edges.end());
result.add(VPackSlice(cached->second->data()));
}
void SingleServerTraversalPath::lastVertexToVelocyPack(Transaction* trx, VPackBuilder& result) {
std::shared_ptr<VPackBuffer<uint8_t>> vertex =
_traverser->fetchVertexData(_path.vertices.back());
result.add(VPackSlice(vertex->data()));
}
DepthFirstTraverser::DepthFirstTraverser(
TraverserOptions& opts, Transaction* trx,
std::unordered_map<size_t, std::vector<TraverserExpression*>> const*
expressions)
: Traverser(opts, expressions), _edgeGetter(this, opts, trx), _trx(trx) {
_defInternalFunctions();
}
bool DepthFirstTraverser::edgeMatchesConditions(VPackSlice e, size_t depth) {
TRI_ASSERT(_expressions != nullptr);
auto it = _expressions->find(depth);
if (it != _expressions->end()) {
for (auto const& exp : it->second) {
TRI_ASSERT(exp != nullptr);
if (exp->isEdgeAccess && !exp->matchesCheck(_trx, e)) {
++_filteredPaths;
return false;
}
}
}
return true;
}
bool DepthFirstTraverser::vertexMatchesConditions(std::string const& v,
size_t depth) {
TRI_ASSERT(_expressions != nullptr);
auto it = _expressions->find(depth);
if (it != _expressions->end()) {
bool fetchVertex = true;
std::shared_ptr<VPackBuffer<uint8_t>> vertex;
for (auto const& exp : it->second) {
TRI_ASSERT(exp != nullptr);
if (!exp->isEdgeAccess) {
if (fetchVertex) {
fetchVertex = false;
vertex = fetchVertexData(v);
}
if (!exp->matchesCheck(_trx, VPackSlice(vertex->data()))) {
++_filteredPaths;
return false;
}
}
}
}
return true;
}
std::shared_ptr<VPackBuffer<uint8_t>> DepthFirstTraverser::fetchVertexData(
std::string const& id) {
auto it = _vertices.find(id);
if (it == _vertices.end()) {
OperationResult opRes =
FetchDocumentById(_trx, id, _builder, _operationOptions);
++_readDocuments;
if (opRes.failed()) {
TRI_ASSERT(opRes.code == TRI_ERROR_ARANGO_DOCUMENT_NOT_FOUND);
VPackBuilder tmp;
tmp.add(VPackValue(VPackValueType::Null));
return tmp.steal();
}
_vertices.emplace(id, opRes.buffer);
return opRes.buffer;
}
return it->second;
}
void DepthFirstTraverser::_defInternalFunctions() {
_getVertex = [this](std::string const& edge, std::string const& vertex, size_t depth,
std::string& result) -> bool {
auto const& it = _edges.find(edge);
TRI_ASSERT(it != _edges.end());
VPackSlice v(it->second->data());
// NOTE: We assume that we only have valid edges.
result = v.get(TRI_VOC_ATTRIBUTE_FROM).copyString();
if (result == vertex) {
result = v.get(TRI_VOC_ATTRIBUTE_TO).copyString();
}
return true;
};
}
void DepthFirstTraverser::setStartVertex(std::string const& v) {
_pruneNext = false;
TRI_ASSERT(_expressions != nullptr);
auto it = _expressions->find(0);
if (it != _expressions->end()) {
if (!it->second.empty()) {
std::shared_ptr<VPackBuffer<uint8_t>> vertex;
bool fetchVertex = true;
for (auto const& exp : it->second) {
TRI_ASSERT(exp != nullptr);
if (!exp->isEdgeAccess) {
if (fetchVertex) {
fetchVertex = false;
OperationResult result = FetchDocumentById(_trx, v, _builder, _operationOptions);
++_readDocuments;
if (result.failed()) {
// Vertex does not exist
_done = true;
return;
}
vertex = result.buffer;
_vertices.emplace(v, vertex);
}
if (!exp->matchesCheck(_trx, VPackSlice(vertex->data()))) {
++_filteredPaths;
_done = true;
return;
}
}
}
}
}
_enumerator.reset(new PathEnumerator<std::string, std::string, VPackValueLength>(
_edgeGetter, _getVertex, v));
_done = false;
}
TraversalPath* DepthFirstTraverser::next() {
TRI_ASSERT(!_done);
if (_pruneNext) {
_pruneNext = false;
_enumerator->prune();
}
TRI_ASSERT(!_pruneNext);
EnumeratedPath<std::string, std::string> const& path = _enumerator->next();
size_t countEdges = path.edges.size();
if (countEdges == 0) {
_done = true;
// Done traversing
return nullptr;
}
auto p = std::make_unique<SingleServerTraversalPath>(path, this);
if (countEdges >= _opts.maxDepth) {
_pruneNext = true;
}
if (countEdges < _opts.minDepth) {
return next();
}
return p.release();
}
bool DepthFirstTraverser::EdgeGetter::nextCursor(std::string const& startVertex,
size_t& eColIdx,
VPackValueLength*& last) {
while (true) {
std::string eColName;
arangodb::Transaction::IndexHandle indexHandle;
if (last != nullptr) {
// The cursor is empty clean up
last = nullptr;
TRI_ASSERT(!_posInCursor.empty());
TRI_ASSERT(!_cursors.empty());
TRI_ASSERT(!_results.empty());
_posInCursor.pop();
_cursors.pop();
_results.pop();
}
if (!_opts.getCollectionAndSearchValue(eColIdx, startVertex, eColName, indexHandle,
_builder)) {
// If we get here there are no valid edges at all
return false;
}
std::shared_ptr<OperationCursor> cursor = _trx->indexScan(
eColName, arangodb::Transaction::CursorType::INDEX, indexHandle,
_builder.slice(), 0, UINT64_MAX, TRI_DEFAULT_BATCH_SIZE, false);
if (cursor->failed()) {
// Some error, ignore and go to next
eColIdx++;
continue;
}
TRI_ASSERT(_posInCursor.size() == _cursors.size());
_cursors.push(cursor);
_results.emplace(std::make_shared<OperationResult>(TRI_ERROR_NO_ERROR));
return true;
}
}
void DepthFirstTraverser::EdgeGetter::nextEdge(
std::string const& startVertex, size_t& eColIdx, VPackValueLength*& last,
std::vector<std::string>& edges) {
if (last == nullptr) {
_posInCursor.push(0);
last = &_posInCursor.top();
} else {
++(*last);
}
while (true) {
TRI_ASSERT(!_cursors.empty());
auto cursor = _cursors.top();
TRI_ASSERT(!_results.empty());
auto opRes = _results.top();
TRI_ASSERT(opRes != nullptr);
// note: we need to check *first* that there is actually something in the buffer
// before we access its internals. otherwise, the buffer contents are uninitialized
// and non-deterministic behavior will be the consequence
VPackSlice edge = opRes->slice();
if (opRes->buffer->empty() || !edge.isArray() || edge.length() <= *last) {
if (cursor->hasMore()) {
// Fetch next and try again
cursor->getMore(opRes);
TRI_ASSERT(last != nullptr);
*last = 0;
edge = opRes->slice();
TRI_ASSERT(edge.isArray());
_traverser->_readDocuments += edge.length();
continue;
}
eColIdx++;
if (!nextCursor(startVertex, eColIdx, last)) {
// No further edges.
TRI_ASSERT(last == nullptr);
TRI_ASSERT(_cursors.size() == _posInCursor.size());
TRI_ASSERT(_cursors.size() == _results.size());
return;
}
// There is a new Cursor on top of the stack, try it
_posInCursor.push(0);
last = &_posInCursor.top();
continue;
}
edge = edge.at(*last);
if (!_traverser->edgeMatchesConditions(edge, edges.size())) {
TRI_ASSERT(last != nullptr);
(*last)++;
continue;
}
std::string id = _trx->extractIdString(edge);
// test if edge is already on this path
auto found = std::find(edges.begin(), edges.end(), id);
if (found != edges.end()) {
// This edge is already on the path, next
TRI_ASSERT(last != nullptr);
(*last)++;
continue;
}
VPackBuilder tmpBuilder = VPackBuilder::clone(edge);
_traverser->_edges.emplace(id, tmpBuilder.steal());
std::string other;
_traverser->_getVertex(id, startVertex, 0, other);
if (!_traverser->vertexMatchesConditions(other, edges.size() + 1)) {
// Retry with the next element
TRI_ASSERT(last != nullptr);
(*last)++;
continue;
}
edges.emplace_back(id);
return;
}
}
void DepthFirstTraverser::EdgeGetter::operator()(
std::string const& startVertex,
std::vector<std::string>& edges, VPackValueLength*& last, size_t& eColIdx,
bool& dir) {
if (last == nullptr) {
eColIdx = 0;
if (!nextCursor(startVertex, eColIdx, last)) {
// We were not able to find any edge
return;
}
}
nextEdge(startVertex, eColIdx, last, edges);
}
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