Line data    Source code

       1             : /******************************************************************************
       2             :  *
       3             :  * Project:  OpenGIS Simple Features Reference Implementation
       4             :  * Purpose:  Streaming parser for GeoJSON-like FeatureCollection
       5             :  * Author:   Even Rouault <even.rouault at spatialys.com>
       6             :  *
       7             :  ******************************************************************************
       8             :  * Copyright (c) 2017, Even Rouault <even.rouault at spatialys.com>
       9             :  *
      10             :  * SPDX-License-Identifier: MIT
      11             :  ****************************************************************************/
      12             : 
      13             : #ifndef OGRJSONCOLLECTIONSTREAMING_PARSER_H_INCLUDED
      14             : #define OGRJSONCOLLECTIONSTREAMING_PARSER_H_INCLUDED
      15             : 
      16             : #include "cpl_json_streaming_parser.h"
      17             : 
      18             : #include <json.h>  // JSON-C
      19             : 
      20             : /************************************************************************/
      21             : /*                      OGRJSONCollectionStreamingParser                */
      22             : /************************************************************************/
      23             : 
      24             : /** Streaming parser for GeoJSON-like FeatureCollection */
      25             : class OGRJSONCollectionStreamingParser CPL_NON_FINAL
      26             :     : public CPLJSonStreamingParser
      27             : {
      28             :     bool m_bFirstPass = false;
      29             : 
      30             :     int m_nDepth = 0;
      31             :     bool m_bInFeatures = false;
      32             :     bool m_bCanEasilyAppend = false;
      33             :     bool m_bInFeaturesArray = false;
      34             :     bool m_bInCoordinates = false;
      35             :     bool m_bInType = false;
      36             :     bool m_bIsTypeKnown = false;
      37             :     bool m_bIsFeatureCollection = false;
      38             :     json_object *m_poRootObj = nullptr;
      39             :     size_t m_nRootObjMemEstimate = 0;
      40             :     json_object *m_poCurObj = nullptr;
      41             :     size_t m_nCurObjMemEstimate = 0;
      42             :     GUIntBig m_nTotalOGRFeatureMemEstimate = 0;
      43             :     bool m_bKeySet = false;
      44             :     std::string m_osCurKey{};
      45             :     std::vector<json_object *> m_apoCurObj{};
      46             :     std::vector<bool> m_abFirstMember{};
      47             :     bool m_bStoreNativeData = false;
      48             :     std::string m_osJson{};
      49             :     size_t m_nMaxObjectSize = 0;
      50             : 
      51             :     bool m_bStartFeature = false;
      52             :     bool m_bEndFeature = false;
      53             : 
      54             :     void AppendObject(json_object *poNewObj);
      55             : 
      56             :     CPL_DISALLOW_COPY_ASSIGN(OGRJSONCollectionStreamingParser)
      57             : 
      58             :   protected:
      59         103 :     inline bool IsFirstPass() const
      60             :     {
      61         103 :         return m_bFirstPass;
      62             :     }
      63             : 
      64             :     virtual void GotFeature(json_object *poObj, bool bFirstPass,
      65             :                             const std::string &osJson) = 0;
      66             :     virtual void TooComplex() = 0;
      67             : 
      68             :   public:
      69             :     OGRJSONCollectionStreamingParser(bool bFirstPass, bool bStoreNativeData,
      70             :                                      size_t nMaxObjectSize);
      71             :     ~OGRJSONCollectionStreamingParser();
      72             : 
      73             :     virtual void String(const char * /*pszValue*/, size_t) override;
      74             :     virtual void Number(const char * /*pszValue*/, size_t) override;
      75             :     virtual void Boolean(bool b) override;
      76             :     virtual void Null() override;
      77             : 
      78             :     virtual void StartObject() override;
      79             :     virtual void EndObject() override;
      80             :     virtual void StartObjectMember(const char * /*pszKey*/, size_t) override;
      81             : 
      82             :     virtual void StartArray() override;
      83             :     virtual void EndArray() override;
      84             :     virtual void StartArrayMember() override;
      85             : 
      86             :     virtual void Exception(const char * /*pszMessage*/) override;
      87             : 
      88             :     json_object *StealRootObject();
      89             : 
      90         861 :     inline bool IsTypeKnown() const
      91             :     {
      92         861 :         return m_bIsTypeKnown;
      93             :     }
      94             : 
      95         859 :     inline bool IsFeatureCollection() const
      96             :     {
      97         859 :         return m_bIsFeatureCollection;
      98             :     }
      99             : 
     100         265 :     inline GUIntBig GetTotalOGRFeatureMemEstimate() const
     101             :     {
     102         265 :         return m_nTotalOGRFeatureMemEstimate;
     103             :     }
     104             : 
     105         265 :     inline bool CanEasilyAppend() const
     106             :     {
     107         265 :         return m_bCanEasilyAppend;
     108             :     }
     109             : 
     110        1668 :     inline void ResetFeatureDetectionState()
     111             :     {
     112        1668 :         m_bStartFeature = false;
     113        1668 :         m_bEndFeature = false;
     114        1668 :     }
     115             : 
     116        1668 :     inline bool IsStartFeature() const
     117             :     {
     118        1668 :         return m_bStartFeature;
     119             :     }
     120             : 
     121        1650 :     inline bool IsEndFeature() const
     122             :     {
     123        1650 :         return m_bEndFeature;
     124             :     }
     125             : };
     126             : 
     127             : #endif  // OGRJSONCOLLECTIONSTREAMING_PARSER_H_INCLUDED