rocksdb/include/utilities/geo_db.h

106 lines
3.2 KiB
C++

// Copyright (c) 2013, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
//
#ifndef ROCKSDB_LITE
#pragma once
#include <string>
#include <vector>
#include "utilities/stackable_db.h"
#include "rocksdb/status.h"
namespace rocksdb {
//
// Configurable options needed for setting up a Geo database
//
struct GeoDBOptions {
// Backup info and error messages will be written to info_log
// if non-nullptr.
// Default: nullptr
Logger* info_log;
explicit GeoDBOptions(Logger* _info_log = nullptr):info_log(_info_log) { }
};
//
// A position in the earth's geoid
//
class GeoPosition {
public:
double latitude;
double longitude;
explicit GeoPosition(double la = 0, double lo = 0) :
latitude(la), longitude(lo) {
}
};
//
// Description of an object on the Geoid. It is located by a GPS location,
// and is identified by the id. The value associated with this object is
// an opaque string 'value'. Different objects identified by unique id's
// can have the same gps-location associated with them.
//
class GeoObject {
public:
GeoPosition position;
std::string id;
std::string value;
GeoObject() {}
GeoObject(const GeoPosition& pos, const std::string& i,
const std::string& val) :
position(pos), id(i), value(val) {
}
};
//
// Stack your DB with GeoDB to be able to get geo-spatial support
//
class GeoDB : public StackableDB {
public:
// GeoDBOptions have to be the same as the ones used in a previous
// incarnation of the DB
//
// GeoDB owns the pointer `DB* db` now. You should not delete it or
// use it after the invocation of GeoDB
// GeoDB(DB* db, const GeoDBOptions& options) : StackableDB(db) {}
GeoDB(DB* db, const GeoDBOptions& options) : StackableDB(db) {}
virtual ~GeoDB() {}
// Insert a new object into the location database. The object is
// uniquely identified by the id. If an object with the same id already
// exists in the db, then the old one is overwritten by the new
// object being inserted here.
virtual Status Insert(const GeoObject& object) = 0;
// Retrieve the value of the object located at the specified GPS
// location and is identified by the 'id'.
virtual Status GetByPosition(const GeoPosition& pos,
const Slice& id, std::string* value) = 0;
// Retrieve the value of the object identified by the 'id'. This method
// could be potentially slower than GetByPosition
virtual Status GetById(const Slice& id, GeoObject* object) = 0;
// Delete the specified object
virtual Status Remove(const Slice& id) = 0;
// Returns a list of all items within a circular radius from the
// specified gps location. If 'number_of_values' is specified,
// then this call returns at most that many number of objects.
// The radius is specified in 'meters'.
virtual Status SearchRadial(const GeoPosition& pos,
double radius,
std::vector<GeoObject>* values,
int number_of_values = INT_MAX) = 0;
};
} // namespace rocksdb
#endif // ROCKSDB_LITE