C++ VPackBuilder类代码示例

  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 = arangodb::Transaction::extractFromFromDocument(edge);
        if (from == v) {
          VPackSlice to = arangodb::Transaction::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());
    }
  }

TraverserExpression::TraverserExpression(VPackSlice const& slice) {
  isEdgeAccess = slice.get("isEdgeAccess").getBool();
  comparisonType = static_cast<aql::AstNodeType>(
      slice.get("comparisonType").getNumber<uint32_t>());
  auto registerNode = [&](aql::AstNode const* node)
                          -> void { _nodeRegister.emplace_back(node); };

  auto registerString = [&](std::string const& str) -> char const* {
    auto copy = std::make_unique<std::string>(str.c_str(), str.size());

    _stringRegister.emplace_back(copy.get());
    auto p = copy.release();
    TRI_ASSERT(p != nullptr);
    TRI_ASSERT(p->c_str() != nullptr);
    return p->c_str();  // should never change its position, even if vector
                        // grows/shrinks
  };

  VPackSlice compareToSlice = slice.get("compareTo");
  VPackBuilder* builder = new VPackBuilder;
  try {
    builder->add(compareToSlice);
  } catch (...) {
    delete builder;
    throw;
  }
  compareTo.reset(builder);
  // If this fails everything before does not leak
  varAccess = new aql::AstNode(registerNode, registerString, slice.get("varAccess"));
}

void RemoveNode::toVelocyPackHelper(VPackBuilder& nodes, bool verbose) const {
  ModificationNode::toVelocyPackHelper(nodes, verbose);
  nodes.add(VPackValue("inVariable"));
  _inVariable->toVelocyPack(nodes);

  // And close it:
  nodes.close();
}

void SingleServerTraversalPath::lastEdgeToVelocyPack(arangodb::Transaction* trx, VPackBuilder& result) {
  if (_path.edges.empty()) {
    result.add(arangodb::basics::VelocyPackHelper::NullValue());
    return;
  }
  auto cached = _traverser->_edges.find(_path.edges.back());
  // All edges are cached!!
  TRI_ASSERT(cached != _traverser->_edges.end());
  result.addExternal((*cached).second);
}

void arangodb::traverser::ShortestPath::edgeToVelocyPack(Transaction*, ManagedDocumentResult* mmdr,
                                                         size_t position, VPackBuilder& builder) {
  TRI_ASSERT(position < length());
  if (position == 0) {
    builder.add(basics::VelocyPackHelper::NullValue());
  } else {
    TRI_ASSERT(position - 1 < _edges.size());
    builder.add(_edges[position - 1]);
  }
}

void RestWalHandler::transactions() {
  auto const& info =
      arangodb::wal::LogfileManager::instance()->runningTransactions();
 
  VPackBuilder builder;
  builder.openObject();
  builder.add("runningTransactions", VPackValue(static_cast<double>(std::get<0>(info))));

  // lastCollectedId
  {
    auto value = std::get<1>(info);
    if (value == UINT64_MAX) {
      builder.add("minLastCollected", VPackValue(VPackValueType::Null));
    } else {
      builder.add("minLastCollected", VPackValue(value));
    }
  }

  // lastSealedId
  {
    auto value = std::get<2>(info);
    if (value == UINT64_MAX) {
      builder.add("minLastSealed", VPackValue(VPackValueType::Null));
    } else {
      builder.add("minLastSealed", VPackValue(value));
    }
  }

  builder.close();

  generateResult(rest::ResponseCode::OK, builder.slice());
}

bool RestEdgesHandler::getEdgesForVertexList(
    VPackSlice const ids,
    std::vector<traverser::TraverserExpression*> const& expressions,
    TRI_edge_direction_e direction, SingleCollectionTransaction& trx,
    VPackBuilder& result, size_t& scannedIndex, size_t& filtered) {
  TRI_ASSERT(ids.isArray());
  trx.orderDitch(trx.cid());  // will throw when it fails

  std::string const collectionName =
      trx.resolver()->getCollectionName(trx.cid());
  Transaction::IndexHandle indexId = trx.edgeIndexHandle(collectionName);

  VPackBuilder searchValueBuilder;
  EdgeIndex::buildSearchValueFromArray(direction, ids, searchValueBuilder);
  VPackSlice search = searchValueBuilder.slice();

  std::unique_ptr<OperationCursor> cursor =
      trx.indexScan(collectionName, arangodb::Transaction::CursorType::INDEX,
                    indexId, search, nullptr, 0, UINT64_MAX, 1000, false);
  if (cursor->failed()) {
    THROW_ARANGO_EXCEPTION(cursor->code);
  }

  auto opRes = std::make_shared<OperationResult>(TRI_ERROR_NO_ERROR);
  while (cursor->hasMore()) {
    cursor->getMore(opRes);
    if (opRes->failed()) {
      THROW_ARANGO_EXCEPTION(opRes->code);
    }
    VPackSlice edges = opRes->slice();
    TRI_ASSERT(edges.isArray());

    // generate result
    scannedIndex += static_cast<size_t>(edges.length());

    for (auto const& edge : VPackArrayIterator(edges)) {
      bool add = true;
      if (!expressions.empty()) {
        for (auto& exp : expressions) {
          if (exp->isEdgeAccess && !exp->matchesCheck(&trx, edge)) {
            ++filtered;
            add = false;
            break;
          }
        }
      }

      if (add) {
        result.add(edge);
      }
    }
  }

  return true;
}

void RestVocbaseBaseHandler::generatePreconditionFailed(
    VPackSlice const& slice) {
  createResponse(GeneralResponse::ResponseCode::PRECONDITION_FAILED);

  if (slice.isObject()) {  // single document case
    std::string const rev =
        VelocyPackHelper::getStringValue(slice, StaticStrings::RevString, "");
    _response->setHeaderNC(StaticStrings::Etag, "\"" + rev + "\"");
  }
  VPackBuilder builder;
  {
    VPackObjectBuilder guard(&builder);
    builder.add("error", VPackValue(true));
    builder.add("code",
                VPackValue(static_cast<int32_t>(
                    GeneralResponse::ResponseCode::PRECONDITION_FAILED)));
    builder.add("errorNum", VPackValue(TRI_ERROR_ARANGO_CONFLICT));
    builder.add("errorMessage", VPackValue("precondition failed"));
    if (slice.isObject()) {
      builder.add(StaticStrings::IdString, slice.get(StaticStrings::IdString));
      builder.add(StaticStrings::KeyString,
                  slice.get(StaticStrings::KeyString));
      builder.add(StaticStrings::RevString,
                  slice.get(StaticStrings::RevString));
    } else {
      builder.add("result", slice);
    }
  }

  auto transactionContext(StandaloneTransactionContext::Create(_vocbase));
  writeResult(builder.slice(), *(transactionContext->getVPackOptionsForDump()));
}

HttpHandler::status_t RestVersionHandler::execute() {
  try {
    VPackBuilder result;
    result.add(VPackValue(VPackValueType::Object));
    result.add("server", VPackValue("arango"));
    result.add("version", VPackValue(ARANGODB_VERSION));

    bool found;
    std::string const& detailsStr = _request->value("details", found);

    if (found && StringUtils::boolean(detailsStr)) {
      result.add("details", VPackValue(VPackValueType::Object));

      Version::getVPack(result);

      if (application_features::ApplicationServer::server != nullptr) {
        auto server = application_features::ApplicationServer::server
                          ->getFeature<ServerFeature>("Server");
        result.add("mode", VPackValue(server->operationModeString()));
      }

      result.close();
    }
    result.close();
    generateResult(GeneralResponse::ResponseCode::OK, result.slice());
  } catch (...) {
    // Ignore this error
  }
  return status_t(HANDLER_DONE);
}

HttpHandler::status_t RestAuthHandler::execute() {
  auto const type = _request->requestType();
  if (type != GeneralRequest::RequestType::POST) {
    generateError(GeneralResponse::ResponseCode::METHOD_NOT_ALLOWED,
                  TRI_ERROR_HTTP_METHOD_NOT_ALLOWED);
    return status_t(HANDLER_DONE);
  }

  VPackOptions options = VPackOptions::Defaults;
  options.checkAttributeUniqueness = true;

  bool parseSuccess;
  std::shared_ptr<VPackBuilder> parsedBody =
      parseVelocyPackBody(&options, parseSuccess);
  if (!parseSuccess) {
    return badRequest();
  }
  
  VPackSlice slice = parsedBody->slice(); 
  if (!slice.isObject()) {
    return badRequest();
  }

  VPackSlice usernameSlice = slice.get("username");
  VPackSlice passwordSlice = slice.get("password");

  if (!usernameSlice.isString() || !passwordSlice.isString()) {
    return badRequest();
  }

  std::string const username = usernameSlice.copyString();
  std::string const password = passwordSlice.copyString();
  
  AuthResult auth = RestServerFeature::AUTH_INFO.checkPassword(username, password);

  if (auth._authorized) {
    VPackBuilder resultBuilder;
    {
      VPackObjectBuilder b(&resultBuilder);
      std::string jwt = generateJwt(username, password);
      resultBuilder.add("jwt", VPackValue(jwt));
      resultBuilder.add("must_change_password", VPackValue(auth._mustChange));
    }
    
    generateDocument(resultBuilder.slice(), true, &VPackOptions::Defaults);
    return status_t(HANDLER_DONE);
  } else {
    // mop: rfc 2616 10.4.2 (if credentials wrong 401)
    generateError(GeneralResponse::ResponseCode::UNAUTHORIZED, TRI_ERROR_HTTP_UNAUTHORIZED,
                  "Wrong credentials");
    return status_t(HANDLER_DONE);
  }
}

VPackBuilder* TransactionContext::leaseBuilder() {
  if (_builders.empty()) {
    // create a new builder and return it
    return new VPackBuilder();
  }

  // re-use an existing builder
  VPackBuilder* b = _builders.back();
  b->clear();
  _builders.pop_back();

  return b;
}

void arangodb::traverser::TraverserOptions::toVelocyPack(VPackBuilder& builder) const {
  VPackObjectBuilder guard(&builder);

  builder.add("minDepth", VPackValue(minDepth));
  builder.add("maxDepth", VPackValue(maxDepth));
  builder.add("bfs", VPackValue(useBreadthFirst));

  switch (uniqueVertices) {
    case arangodb::traverser::TraverserOptions::UniquenessLevel::NONE:
      builder.add("uniqueVertices", VPackValue("none"));
      break;
    case arangodb::traverser::TraverserOptions::UniquenessLevel::PATH:
      builder.add("uniqueVertices", VPackValue("path"));
      break;
    case arangodb::traverser::TraverserOptions::UniquenessLevel::GLOBAL:
      builder.add("uniqueVertices", VPackValue("global"));
      break;
  }

  switch (uniqueEdges) {
    case arangodb::traverser::TraverserOptions::UniquenessLevel::NONE:
      builder.add("uniqueEdges", VPackValue("none"));
      break;
    case arangodb::traverser::TraverserOptions::UniquenessLevel::PATH:
      builder.add("uniqueEdges", VPackValue("path"));
      break;
    case arangodb::traverser::TraverserOptions::UniquenessLevel::GLOBAL:
      builder.add("uniqueEdges", VPackValue("global"));
      break;
  }
}

std::string AuthInfo::generateJwt(VPackBuilder const& payload) {
  if (!payload.slice().isObject()) {
    std::string error = "Need an object to generate a JWT. Got: ";
    error += payload.slice().typeName();
    throw std::runtime_error(error);
  }
  bool hasIss = payload.slice().hasKey("iss");
  bool hasIat = payload.slice().hasKey("iat");
  VPackBuilder bodyBuilder;
  if (hasIss && hasIat) {
    bodyBuilder = payload;
  } else {
    VPackObjectBuilder p(&bodyBuilder);
    if (!hasIss) {
      bodyBuilder.add("iss", VPackValue("arangodb"));
    }
    if (!hasIat) {
      bodyBuilder.add("iat", VPackValue(TRI_microtime() / 1000));
    }
    for (auto const& obj : VPackObjectIterator(payload.slice())) {
      bodyBuilder.add(obj.key.copyString(), obj.value);
    }
  }
  return generateRawJwt(bodyBuilder);
}

int Syncer::createCollection(VPackSlice const& slice, arangodb::LogicalCollection** dst) {
  if (dst != nullptr) {
    *dst = nullptr;
  }

  if (!slice.isObject()) {
    return TRI_ERROR_REPLICATION_INVALID_RESPONSE;
  }

  std::string const name = VelocyPackHelper::getStringValue(slice, "name", "");

  if (name.empty()) {
    return TRI_ERROR_REPLICATION_INVALID_RESPONSE;
  }

  TRI_voc_cid_t const cid = getCid(slice);

  if (cid == 0) {
    return TRI_ERROR_REPLICATION_INVALID_RESPONSE;
  }

  TRI_col_type_e const type = static_cast<TRI_col_type_e>(VelocyPackHelper::getNumericValue<int>(
      slice, "type", TRI_COL_TYPE_DOCUMENT));

  arangodb::LogicalCollection* col = getCollectionByIdOrName(cid, name);

  if (col != nullptr && col->type() == type) {
    // collection already exists. TODO: compare attributes
    return TRI_ERROR_NO_ERROR;
  }

  // merge in "isSystem" attribute
  VPackBuilder s;
  s.openObject();
  s.add("isSystem", VPackValue(true));
  s.close();

  VPackBuilder merged = VPackCollection::merge(s.slice(), slice, true);

  int res = TRI_ERROR_NO_ERROR;
  try {
    col = _vocbase->createCollection(merged.slice(), cid, true);
  } catch (basics::Exception const& ex) {
    res = ex.code();
  } catch (...) {
    res = TRI_ERROR_INTERNAL;
  }

  if (res != TRI_ERROR_NO_ERROR) {
    return res;
  }

  TRI_ASSERT(col != nullptr);

  if (dst != nullptr) {
    *dst = col;
  }

  return TRI_ERROR_NO_ERROR;
}

std::string AuthInfo::generateRawJwt(VPackBuilder const& bodyBuilder) {
  VPackBuilder headerBuilder;
  {
    VPackObjectBuilder h(&headerBuilder);
    headerBuilder.add("alg", VPackValue("HS256"));
    headerBuilder.add("typ", VPackValue("JWT"));
  }

  std::string fullMessage(StringUtils::encodeBase64(headerBuilder.toJson()) +
                          "." +
                          StringUtils::encodeBase64(bodyBuilder.toJson()));

  std::string signature =
      sslHMAC(_jwtSecret.c_str(), _jwtSecret.length(), fullMessage.c_str(),
              fullMessage.length(), SslInterface::Algorithm::ALGORITHM_SHA256);

  return fullMessage + "." + StringUtils::encodeBase64U(signature);
}