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             :  * Permission is hereby granted, free of charge, to any person obtaining a
      11             :  * copy of this software and associated documentation files (the "Software"),
      12             :  * to deal in the Software without restriction, including without limitation
      13             :  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
      14             :  * and/or sell copies of the Software, and to permit persons to whom the
      15             :  * Software is furnished to do so, subject to the following conditions:
      16             :  *
      17             :  * The above copyright notice and this permission notice shall be included
      18             :  * in all copies or substantial portions of the Software.
      19             :  *
      20             :  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
      21             :  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
      22             :  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
      23             :  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
      24             :  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
      25             :  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
      26             :  * DEALINGS IN THE SOFTWARE.
      27             :  ****************************************************************************/
      28             : 
      29             : #ifndef OGRJSONCOLLECTIONSTREAMING_PARSER_H_INCLUDED
      30             : #define OGRJSONCOLLECTIONSTREAMING_PARSER_H_INCLUDED
      31             : 
      32             : #include "cpl_json_streaming_parser.h"
      33             : 
      34             : #include <json.h>  // JSON-C
      35             : 
      36             : /************************************************************************/
      37             : /*                      OGRJSONCollectionStreamingParser                */
      38             : /************************************************************************/
      39             : 
      40             : /** Streaming parser for GeoJSON-like FeatureCollection */
      41             : class OGRJSONCollectionStreamingParser CPL_NON_FINAL
      42             :     : public CPLJSonStreamingParser
      43             : {
      44             :     bool m_bFirstPass = false;
      45             : 
      46             :     int m_nDepth = 0;
      47             :     bool m_bInFeatures = false;
      48             :     bool m_bCanEasilyAppend = false;
      49             :     bool m_bInFeaturesArray = false;
      50             :     bool m_bInCoordinates = false;
      51             :     bool m_bInType = false;
      52             :     bool m_bIsTypeKnown = false;
      53             :     bool m_bIsFeatureCollection = false;
      54             :     json_object *m_poRootObj = nullptr;
      55             :     size_t m_nRootObjMemEstimate = 0;
      56             :     json_object *m_poCurObj = nullptr;
      57             :     size_t m_nCurObjMemEstimate = 0;
      58             :     GUIntBig m_nTotalOGRFeatureMemEstimate = 0;
      59             :     bool m_bKeySet = false;
      60             :     std::string m_osCurKey{};
      61             :     std::vector<json_object *> m_apoCurObj{};
      62             :     std::vector<bool> m_abFirstMember{};
      63             :     bool m_bStoreNativeData = false;
      64             :     std::string m_osJson{};
      65             :     size_t m_nMaxObjectSize = 0;
      66             : 
      67             :     bool m_bStartFeature = false;
      68             :     bool m_bEndFeature = false;
      69             : 
      70             :     void AppendObject(json_object *poNewObj);
      71             : 
      72             :     CPL_DISALLOW_COPY_ASSIGN(OGRJSONCollectionStreamingParser)
      73             : 
      74             :   protected:
      75         103 :     inline bool IsFirstPass() const
      76             :     {
      77         103 :         return m_bFirstPass;
      78             :     }
      79             : 
      80             :     virtual void GotFeature(json_object *poObj, bool bFirstPass,
      81             :                             const std::string &osJson) = 0;
      82             :     virtual void TooComplex() = 0;
      83             : 
      84             :   public:
      85             :     OGRJSONCollectionStreamingParser(bool bFirstPass, bool bStoreNativeData,
      86             :                                      size_t nMaxObjectSize);
      87             :     ~OGRJSONCollectionStreamingParser();
      88             : 
      89             :     virtual void String(const char * /*pszValue*/, size_t) override;
      90             :     virtual void Number(const char * /*pszValue*/, size_t) override;
      91             :     virtual void Boolean(bool b) override;
      92             :     virtual void Null() override;
      93             : 
      94             :     virtual void StartObject() override;
      95             :     virtual void EndObject() override;
      96             :     virtual void StartObjectMember(const char * /*pszKey*/, size_t) override;
      97             : 
      98             :     virtual void StartArray() override;
      99             :     virtual void EndArray() override;
     100             :     virtual void StartArrayMember() override;
     101             : 
     102             :     virtual void Exception(const char * /*pszMessage*/) override;
     103             : 
     104             :     json_object *StealRootObject();
     105             : 
     106         709 :     inline bool IsTypeKnown() const
     107             :     {
     108         709 :         return m_bIsTypeKnown;
     109             :     }
     110             : 
     111         707 :     inline bool IsFeatureCollection() const
     112             :     {
     113         707 :         return m_bIsFeatureCollection;
     114             :     }
     115             : 
     116         241 :     inline GUIntBig GetTotalOGRFeatureMemEstimate() const
     117             :     {
     118         241 :         return m_nTotalOGRFeatureMemEstimate;
     119             :     }
     120             : 
     121         241 :     inline bool CanEasilyAppend() const
     122             :     {
     123         241 :         return m_bCanEasilyAppend;
     124             :     }
     125             : 
     126        1668 :     inline void ResetFeatureDetectionState()
     127             :     {
     128        1668 :         m_bStartFeature = false;
     129        1668 :         m_bEndFeature = false;
     130        1668 :     }
     131             : 
     132        1668 :     inline bool IsStartFeature() const
     133             :     {
     134        1668 :         return m_bStartFeature;
     135             :     }
     136             : 
     137        1650 :     inline bool IsEndFeature() const
     138             :     {
     139        1650 :         return m_bEndFeature;
     140             :     }
     141             : };
     142             : 
     143             : #endif  // OGRJSONCOLLECTIONSTREAMING_PARSER_H_INCLUDED