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arangodb/arangod/Cluster/ClusterTraverser.cpp

313 lines
12 KiB
C++

////////////////////////////////////////////////////////////////////////////////
/// @brief Cluster Traverser
///
/// @file
///
/// DISCLAIMER
///
/// Copyright 2014-2015 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
/// @author Copyright 2014-2015, ArangoDB GmbH, Cologne, Germany
/// @author Copyright 2012-2013, triAGENS GmbH, Cologne, Germany
////////////////////////////////////////////////////////////////////////////////
#include "Cluster/ClusterTraverser.h"
#include "Cluster/ClusterMethods.h"
#include <iostream>
using ClusterTraversalPath = triagens::arango::traverser::ClusterTraversalPath;
using ClusterTraverser = triagens::arango::traverser::ClusterTraverser;
// -----------------------------------------------------------------------------
// --SECTION-- class ClusterTraversalPath
// -----------------------------------------------------------------------------
triagens::basics::Json* ClusterTraversalPath::pathToJson (Transaction*,
CollectionNameResolver*) {
std::unique_ptr<triagens::basics::Json> result(new triagens::basics::Json(triagens::basics::Json::Object));
size_t vCount = _path.vertices.size();
triagens::basics::Json vertices(triagens::basics::Json::Array, vCount);
for (auto& it : _path.vertices) {
vertices.add(*_traverser->vertexToJson(it));
}
triagens::basics::Json edges(triagens::basics::Json::Array, _path.edges.size());
for (auto& it : _path.edges) {
edges.add(*_traverser->edgeToJson(it));
}
result->set("edges", edges);
result->set("vertices", vertices);
return result.release();
}
triagens::basics::Json* ClusterTraversalPath::lastEdgeToJson (Transaction*,
CollectionNameResolver*) {
return _traverser->edgeToJson(_path.edges.back());
}
triagens::basics::Json* ClusterTraversalPath::lastVertexToJson (Transaction*,
CollectionNameResolver*) {
return _traverser->vertexToJson(_path.vertices.back());
}
// -----------------------------------------------------------------------------
// --SECTION-- class ClusterTraverser
// -----------------------------------------------------------------------------
bool ClusterTraverser::VertexGetter::operator() (std::string const& edgeId,
std::string const& vertexId,
size_t depth,
std::string& result) {
auto it = _traverser->_edges.find(edgeId);
std::string def = "";
if (it != _traverser->_edges.end()) {
std::string from = triagens::basics::JsonHelper::getStringValue(it->second, "_from", def);
if (from != vertexId) {
result = from;
}
else {
std::string to = triagens::basics::JsonHelper::getStringValue(it->second, "_to", def);
result = to;
}
auto exp = _traverser->_expressions->find(depth);
if (exp != _traverser->_expressions->end()) {
auto v = _traverser->_vertices.find(result);
if (v == _traverser->_vertices.end()) {
++_traverser->_filteredPaths;
return false;
}
if (! _traverser->vertexMatchesCondition(v->second, exp->second)) {
return false;
}
}
return true;
}
TRI_ASSERT(false);
result = def;
return false;
}
void ClusterTraverser::EdgeGetter::operator() (std::string const& startVertex,
std::vector<std::string>& result,
size_t*& last,
size_t& eColIdx,
bool& unused) {
if (eColIdx >= _traverser->_edgeCols.size()) {
// Nothing to do, caller has set a defined state already.
return;
}
size_t depth = result.size();
if (last == nullptr) {
TRI_ASSERT(_traverser->_iteratorCache.size() == result.size());
// We have to request the next level
triagens::basics::Json resultEdges(triagens::basics::Json::Object);
triagens::rest::HttpResponse::HttpResponseCode responseCode;
std::string contentType;
std::string collName = _traverser->_edgeCols[eColIdx];
std::vector<TraverserExpression*> expEdges;
auto found = _traverser->_expressions->find(depth);
if (found != _traverser->_expressions->end()) {
expEdges = found->second;
}
int res = getFilteredEdgesOnCoordinator(_traverser->_dbname,
collName,
startVertex,
_traverser->_opts.direction,
expEdges,
responseCode,
contentType,
resultEdges);
if (res != TRI_ERROR_NO_ERROR) {
THROW_ARANGO_EXCEPTION(res);
}
triagens::basics::Json edgesJson = resultEdges.get("edges");
size_t read = triagens::basics::JsonHelper::getNumericValue<size_t>(resultEdges.json(), "scannedIndex", 0);
size_t filter = triagens::basics::JsonHelper::getNumericValue<size_t>(resultEdges.json(), "filter", 0);
_traverser->_readDocuments += read;
std::cout << "Added filtered Edges: " << filter << std::endl;
_traverser->_filteredPaths += filter;
size_t count = edgesJson.size();
if (count == 0) {
last = nullptr;
eColIdx++;
operator()(startVertex, result, last, eColIdx, unused);
return;
}
std::stack<std::string> stack;
std::unordered_set<std::string> verticesToFetch;
for (size_t i = 0; i < edgesJson.size(); ++i) {
triagens::basics::Json edge = edgesJson.at(i);
std::string edgeId = triagens::basics::JsonHelper::getStringValue(edge.json(), "_id", "");
stack.push(edgeId);
std::string fromId = triagens::basics::JsonHelper::getStringValue(edge.json(), "_from", "");
if (_traverser->_vertices.find(fromId) == _traverser->_vertices.end()) {
verticesToFetch.emplace(fromId);
}
std::string toId = triagens::basics::JsonHelper::getStringValue(edge.json(), "_to", "");
if (_traverser->_vertices.find(toId) == _traverser->_vertices.end()) {
verticesToFetch.emplace(toId);
}
_traverser->_edges.emplace(edgeId, edge.copy().steal());
}
std::vector<TraverserExpression*> expVertices;
found = _traverser->_expressions->find(depth + 1);
if (found != _traverser->_expressions->end()) {
expVertices = found->second;
}
std::map<std::string, std::string> headers;
size_t beforeFetching = _traverser->_vertices.size();
res = getFilteredDocumentsOnCoordinator(_traverser->_dbname,
expVertices,
headers,
verticesToFetch,
_traverser->_vertices);
if (res != TRI_ERROR_NO_ERROR) {
THROW_ARANGO_EXCEPTION(res);
}
if (! expVertices.empty()) {
// There are some vertices that either do not exist or do not match the filter.
// We have to exclude these from the traversal
_traverser->_filteredPaths += _traverser->_vertices.size() - beforeFetching;
std::cout << "Added filtered vertices: " << _traverser->_vertices.size() - beforeFetching << std::endl;
}
_traverser->_readDocuments += verticesToFetch.size();
std::string next = stack.top();
stack.pop();
last = &_continueConst;
result.push_back(next);
_traverser->_iteratorCache.emplace(stack);
}
else {
if (_traverser->_iteratorCache.empty()) {
last = nullptr;
return;
}
std::stack<std::string>& tmp = _traverser->_iteratorCache.top();
if (tmp.empty()) {
_traverser->_iteratorCache.pop();
last = nullptr;
eColIdx++;
operator()(startVertex, result, last, eColIdx, unused);
return;
}
else {
std::string next = tmp.top();
tmp.pop();
result.push_back(next);
}
}
}
void ClusterTraverser::setStartVertex (VertexId& v) {
std::string id = v.toString(_resolver);
_enumerator.reset(new triagens::basics::PathEnumerator<std::string, std::string, size_t> (_edgeGetter, _vertexGetter, id));
_done = false;
auto it = _vertices.find(id);
if (it == _vertices.end()) {
triagens::rest::HttpResponse::HttpResponseCode responseCode;
std::map<std::string, std::string> headers;
std::map<std::string, std::string> resultHeaders;
std::vector<std::string> splitId = triagens::basics::StringUtils::split(id, '/');
TRI_ASSERT(splitId.size() == 2);
std::string vertexResult;
int res = getDocumentOnCoordinator(_dbname,
splitId[0],
splitId[1],
0,
headers,
true,
responseCode,
resultHeaders,
vertexResult);
if (res != TRI_ERROR_NO_ERROR) {
THROW_ARANGO_EXCEPTION(res);
}
++_readDocuments;
if (responseCode == triagens::rest::HttpResponse::HttpResponseCode::NOT_FOUND) {
_vertices.emplace(id, nullptr);
}
else {
_vertices.emplace(id, triagens::basics::JsonHelper::fromString(vertexResult));
}
it = _vertices.find(id);
}
auto exp = _expressions->find(0);
if (exp != _expressions->end() && ! vertexMatchesCondition(it->second, exp->second)) {
std::cout << "Filtered on set start vertex\n";
// We can stop here. The start vertex does not match condition
_done = true;
}
}
bool ClusterTraverser::vertexMatchesCondition (TRI_json_t* v, std::vector<TraverserExpression*> const& exp) {
for (auto const& e : exp) {
if (! e->isEdgeAccess) {
if (v == nullptr || ! e->matchesCheck(v)) {
++_filteredPaths;
return false;
}
}
}
return true;
}
triagens::arango::traverser::TraversalPath* ClusterTraverser::next () {
TRI_ASSERT(!_done);
if (_pruneNext) {
_pruneNext = false;
_enumerator->prune();
}
TRI_ASSERT(!_pruneNext);
const triagens::basics::EnumeratedPath<std::string, std::string>& path = _enumerator->next();
size_t countEdges = path.edges.size();
if (countEdges == 0) {
_done = true;
// Done traversing
return nullptr;
}
std::unique_ptr<ClusterTraversalPath> p(new ClusterTraversalPath(this, path));
if (_opts.shouldPrunePath(p.get())) {
_enumerator->prune();
return next();
}
if (countEdges >= _opts.maxDepth) {
_pruneNext = true;
}
if (countEdges < _opts.minDepth) {
return next();
}
return p.release();
}
triagens::basics::Json* ClusterTraverser::edgeToJson (std::string id) const {
auto it = _edges.find(id);
TRI_ASSERT(it != _edges.end());
return new triagens::basics::Json(TRI_UNKNOWN_MEM_ZONE, TRI_CopyJson(TRI_UNKNOWN_MEM_ZONE, it->second));
}
triagens::basics::Json* ClusterTraverser::vertexToJson (std::string id) const {
auto it = _vertices.find(id);
TRI_ASSERT(it != _vertices.end());
return new triagens::basics::Json(TRI_UNKNOWN_MEM_ZONE, TRI_CopyJson(TRI_UNKNOWN_MEM_ZONE, it->second));
}