--- /dev/null
+/**********************************************************************
+ *
+ * PostGIS - Spatial Types for PostgreSQL
+ * Copyright 2011 Kashif Rasul <kashif.rasul@gmail.com>
+ *
+ * This is free software; you can redistribute and/or modify it under
+ * the terms of the GNU General Public Licence. See the COPYING file.
+ *
+ **********************************************************************/
+
+#include "postgres.h"
+#include "lwgeom_pg.h"
+#include "liblwgeom.h"
+#include <assert.h>
+
+Datum geom_from_geojson(PG_FUNCTION_ARGS);
+
+
+static void geojson_lwerror(char *msg, int error_code)
+{
+ POSTGIS_DEBUGF(3, "ST_GeomFromGeoJSON ERROR %i", error_code);
+ lwerror("%s", msg);
+}
+
+#ifdef HAVE_LIBJSON
+
+#include "lwgeom_export.h"
+#include <json/json.h>
+#include <json/json_object_private.h>
+
+/* Prototype */
+LWGEOM* parse_geojson(json_object *geojson, bool *hasz, int *root_srid);
+
+static json_object*
+findMemberByName(json_object* poObj, const char* pszName )
+{
+ json_object* poTmp;
+ json_object_iter it;
+
+ poTmp = poObj;
+
+ if( NULL == pszName || NULL == poObj)
+ return NULL;
+
+ it.key = NULL;
+ it.val = NULL;
+ it.entry = NULL;
+
+ if( NULL != json_object_get_object(poTmp) )
+ {
+ assert( NULL != json_object_get_object(poTmp)->head );
+
+ for( it.entry = json_object_get_object(poTmp)->head;
+ ( it.entry ?
+ ( it.key = (char*)it.entry->k,
+ it.val = (json_object*)it.entry->v, it.entry) : 0);
+ it.entry = it.entry->next)
+ {
+ if( strcasecmp((char *)it.key, pszName )==0 )
+ return it.val;
+ }
+ }
+
+ return NULL;
+}
+
+
+static int
+parse_geojson_coord(json_object *poObj, bool *hasz, POINTARRAY *pa)
+{
+ POINT4D pt;
+ int iType = 0;
+
+ POSTGIS_DEBUGF(3, "parse_geojson_coord called for object %s.", json_object_to_json_string( poObj ) );
+
+ if( json_type_array == json_object_get_type( poObj ) )
+ {
+
+ json_object* poObjCoord = NULL;
+ const int nSize = json_object_array_length( poObj );
+ POSTGIS_DEBUGF(3, "parse_geojson_coord called for array size %d.", nSize );
+
+
+ // Read X coordinate
+ poObjCoord = json_object_array_get_idx( poObj, 0 );
+ iType = json_object_get_type(poObjCoord);
+ if (iType == json_type_double)
+ pt.x = json_object_get_double( poObjCoord );
+ else
+ pt.x = json_object_get_int( poObjCoord );
+ POSTGIS_DEBUGF(3, "parse_geojson_coord pt.x = %f.", pt.x );
+
+ // Read Y coordiante
+ poObjCoord = json_object_array_get_idx( poObj, 1 );
+ if (iType == json_type_double)
+ pt.y = json_object_get_double( poObjCoord );
+ else
+ pt.y = json_object_get_int( poObjCoord );
+ POSTGIS_DEBUGF(3, "parse_geojson_coord pt.y = %f.", pt.y );
+
+ *hasz = false;
+
+ if( nSize == 3 )
+ {
+ // Read Z coordiante
+ poObjCoord = json_object_array_get_idx( poObj, 2 );
+ if (iType == 3)
+ pt.z = json_object_get_double( poObjCoord );
+ else
+ pt.z = json_object_get_int( poObjCoord );
+ POSTGIS_DEBUGF(3, "parse_geojson_coord pt.z = %f.", pt.z );
+ *hasz = true;
+ }
+ }
+
+ return ptarray_append_point(pa, &pt, LW_FALSE);
+}
+
+static LWGEOM*
+parse_geojson_point(json_object *geojson, bool *hasz, int *root_srid)
+{
+ LWGEOM *geom;
+ POINTARRAY *pa;
+ json_object* coords = NULL;
+
+ POSTGIS_DEBUGF(3, "parse_geojson_point called with root_srid = %d.", *root_srid );
+
+ coords = findMemberByName( geojson, "coordinates" );
+
+ pa = ptarray_construct_empty(1, 0, 1);
+ parse_geojson_coord(coords, hasz, pa);
+
+ geom = (LWGEOM *) lwpoint_construct(*root_srid, NULL, pa);
+ POSTGIS_DEBUG(2, "parse_geojson_point finished.");
+ return geom;
+}
+
+static LWGEOM*
+parse_geojson_linestring(json_object *geojson, bool *hasz, int *root_srid)
+{
+ LWGEOM *geom;
+ POINTARRAY *pa;
+ json_object* points = NULL;
+ int i = 0;
+
+ POSTGIS_DEBUG(2, "parse_geojson_linestring called.");
+
+ points = findMemberByName( geojson, "coordinates" );
+
+ pa = ptarray_construct_empty(1, 0, 1);
+
+ if( json_type_array == json_object_get_type( points ) )
+ {
+ const int nPoints = json_object_array_length( points );
+ for(i = 0; i < nPoints; ++i)
+ {
+ json_object* coords = NULL;
+ coords = json_object_array_get_idx( points, i );
+ parse_geojson_coord(coords, hasz, pa);
+ }
+ }
+
+ geom = (LWGEOM *) lwline_construct(*root_srid, NULL, pa);
+
+ POSTGIS_DEBUG(2, "parse_geojson_linestring finished.");
+ return geom;
+}
+
+static LWGEOM*
+parse_geojson_polygon(json_object *geojson, bool *hasz, int *root_srid)
+{
+ LWGEOM *geom;
+ POINTARRAY **ppa;
+ json_object* rings = NULL;
+ int i = 0, j = 0;
+ int ring = 0;
+
+ rings = findMemberByName( geojson, "coordinates" );
+
+ ppa = (POINTARRAY**) lwalloc(sizeof(POINTARRAY*));
+
+ if( json_type_array == json_object_get_type( rings ) )
+ {
+ int nPoints;
+ json_object* points = NULL;
+ ppa[0] = ptarray_construct_empty(1, 0, 1);
+ ring = json_object_array_length( rings );
+ points = json_object_array_get_idx( rings, 0 );
+ nPoints = json_object_array_length( points );
+
+ for (i=0; i < nPoints; i++ )
+ {
+ json_object* coords = NULL;
+ coords = json_object_array_get_idx( points, i );
+ parse_geojson_coord(coords, hasz, ppa[0]);
+ }
+
+ for(i = 1; i < ring; ++i)
+ {
+ int nPoints;
+ ppa = (POINTARRAY**) lwrealloc((POINTARRAY *) ppa, sizeof(POINTARRAY*) * (i + 1));
+ ppa[i] = ptarray_construct_empty(1, 0, 1);
+ points = json_object_array_get_idx( rings, i );
+ nPoints = json_object_array_length( points );
+ for (j=0; j < nPoints; j++ )
+ {
+ json_object* coords = NULL;
+ coords = json_object_array_get_idx( points, j );
+ parse_geojson_coord(coords, hasz, ppa[i]);
+ }
+ }
+ }
+
+ geom = (LWGEOM *) lwpoly_construct(*root_srid, NULL, ring, ppa);
+ return geom;
+}
+
+static LWGEOM*
+parse_geojson_multipoint(json_object *geojson, bool *hasz, int *root_srid)
+{
+ LWGEOM *geom;
+ int i = 0;
+ json_object* poObjPoints = NULL;
+
+ if (!*root_srid)
+ {
+ geom = (LWGEOM *)lwcollection_construct_empty(MULTIPOINTTYPE, *root_srid, 1, 0);
+ }
+ else
+ {
+ geom = (LWGEOM *)lwcollection_construct_empty(MULTIPOINTTYPE, -1, 1, 0);
+ }
+
+ poObjPoints = findMemberByName( geojson, "coordinates" );
+
+ if( json_type_array == json_object_get_type( poObjPoints ) )
+ {
+ const int nPoints = json_object_array_length( poObjPoints );
+ for( i = 0; i < nPoints; ++i)
+ {
+ POINTARRAY *pa;
+ json_object* poObjCoords = NULL;
+ poObjCoords = json_object_array_get_idx( poObjPoints, i );
+
+ pa = ptarray_construct_empty(1, 0, 1);
+ parse_geojson_coord(poObjCoords, hasz, pa);
+
+ geom = (LWGEOM*)lwmpoint_add_lwpoint((LWMPOINT*)geom,
+ (LWPOINT*)lwpoint_construct(*root_srid, NULL, pa));
+ }
+ }
+
+ return geom;
+}
+
+static LWGEOM*
+parse_geojson_multilinestring(json_object *geojson, bool *hasz, int *root_srid)
+{
+ LWGEOM *geom = NULL;
+ int i, j;
+ json_object* poObjLines = NULL;
+
+ if (!*root_srid)
+ {
+ geom = (LWGEOM *)lwcollection_construct_empty(MULTILINETYPE, *root_srid, 1, 0);
+ }
+ else
+ {
+ geom = (LWGEOM *)lwcollection_construct_empty(MULTILINETYPE, -1, 1, 0);
+ }
+
+ poObjLines = findMemberByName( geojson, "coordinates" );
+
+ if( json_type_array == json_object_get_type( poObjLines ) )
+ {
+ const int nLines = json_object_array_length( poObjLines );
+ for( i = 0; i < nLines; ++i)
+ {
+ POINTARRAY *pa = NULL;
+ json_object* poObjLine = NULL;
+ poObjLine = json_object_array_get_idx( poObjLines, i );
+ pa = ptarray_construct_empty(1, 0, 1);
+
+ if( json_type_array == json_object_get_type( poObjLine ) )
+ {
+ const int nPoints = json_object_array_length( poObjLine );
+ for(j = 0; j < nPoints; ++j)
+ {
+ json_object* coords = NULL;
+ coords = json_object_array_get_idx( poObjLine, j );
+ parse_geojson_coord(coords, hasz, pa);
+ }
+
+ geom = (LWGEOM*)lwmline_add_lwline((LWMLINE*)geom,
+ (LWLINE*)lwline_construct(*root_srid, NULL, pa));
+ }
+ }
+ }
+
+ return geom;
+}
+
+static LWGEOM*
+parse_geojson_multipolygon(json_object *geojson, bool *hasz, int *root_srid)
+{
+ LWGEOM *geom = NULL;
+ int i, j, k;
+ json_object* poObjPolys = NULL;
+
+ if (!*root_srid)
+ {
+ geom = (LWGEOM *)lwcollection_construct_empty(MULTIPOLYGONTYPE, *root_srid, 1, 0);
+ }
+ else
+ {
+ geom = (LWGEOM *)lwcollection_construct_empty(MULTIPOLYGONTYPE, -1, 1, 0);
+ }
+
+ poObjPolys = findMemberByName( geojson, "coordinates" );
+
+ if( json_type_array == json_object_get_type( poObjPolys ) )
+ {
+ const int nPolys = json_object_array_length( poObjPolys );
+
+ for(i = 0; i < nPolys; ++i)
+ {
+ POINTARRAY **ppa;
+ json_object* poObjPoly = NULL;
+ poObjPoly = json_object_array_get_idx( poObjPolys, i );
+
+ ppa = (POINTARRAY**) lwalloc(sizeof(POINTARRAY*));
+
+ if( json_type_array == json_object_get_type( poObjPoly ) )
+ {
+ int nPoints;
+ json_object* points = NULL;
+ int ring = json_object_array_length( poObjPoly );
+ ppa[0] = ptarray_construct_empty(1, 0, 1);
+
+ points = json_object_array_get_idx( poObjPoly, 0 );
+ nPoints = json_object_array_length( points );
+
+ for (j=0; j < nPoints; j++ )
+ {
+ json_object* coords = NULL;
+ coords = json_object_array_get_idx( points, j );
+ parse_geojson_coord(coords, hasz, ppa[0]);
+ }
+
+ for(j = 1; j < ring; ++j)
+ {
+ int nPoints;
+ ppa = (POINTARRAY**) lwrealloc((POINTARRAY *) ppa, sizeof(POINTARRAY*) * (j + 1));
+ ppa[i] = ptarray_construct_empty(1, 0, 1);
+ points = json_object_array_get_idx( poObjPoly, j );
+
+ nPoints = json_object_array_length( points );
+ for (k=0; k < nPoints; k++ )
+ {
+ json_object* coords = NULL;
+ coords = json_object_array_get_idx( points, k );
+ parse_geojson_coord(coords, hasz, ppa[i]);
+ }
+ }
+
+ geom = (LWGEOM*)lwmpoly_add_lwpoly((LWMPOLY*)geom,
+ (LWPOLY*)lwpoly_construct(*root_srid, NULL, ring, ppa));
+ }
+ }
+ }
+
+ return geom;
+}
+
+static LWGEOM*
+parse_geojson_geometrycollection(json_object *geojson, bool *hasz, int *root_srid)
+{
+ LWGEOM *geom = NULL;
+ int i;
+ json_object* poObjGeoms = NULL;
+
+ if (!*root_srid)
+ {
+ geom = (LWGEOM *)lwcollection_construct_empty(COLLECTIONTYPE, *root_srid, 1, 0);
+ }
+ else
+ {
+ geom = (LWGEOM *)lwcollection_construct_empty(COLLECTIONTYPE, -1, 1, 0);
+ }
+
+ poObjGeoms = findMemberByName( geojson, "geometries" );
+
+ if( json_type_array == json_object_get_type( poObjGeoms ) )
+ {
+ const int nGeoms = json_object_array_length( poObjGeoms );
+ json_object* poObjGeom = NULL;
+ for(i = 0; i < nGeoms; ++i )
+ {
+ poObjGeom = json_object_array_get_idx( poObjGeoms, i );
+ geom = (LWGEOM*)lwcollection_add_lwgeom((LWCOLLECTION *)geom,
+ parse_geojson(poObjGeom, hasz, root_srid));
+ }
+ }
+
+ return geom;
+}
+
+LWGEOM*
+parse_geojson(json_object *geojson, bool *hasz, int *root_srid)
+{
+ json_object* type = NULL;
+ const char* name;
+
+ if( NULL == geojson )
+ geojson_lwerror("invalid GeoJSON representation", 2);
+
+ type = findMemberByName( geojson, "type" );
+ if( NULL == type )
+ geojson_lwerror("unknown GeoJSON type", 3);
+
+ name = json_object_get_string( type );
+
+ if( strcasecmp( name, "Point" )==0 )
+ return parse_geojson_point(geojson, hasz, root_srid);
+
+ if( strcasecmp( name, "LineString" )==0 )
+ return parse_geojson_linestring(geojson, hasz, root_srid);
+
+ if( strcasecmp( name, "Polygon" )==0 )
+ return parse_geojson_polygon(geojson, hasz, root_srid);
+
+ if( strcasecmp( name, "MultiPoint" )==0 )
+ return parse_geojson_multipoint(geojson, hasz, root_srid);
+
+ if( strcasecmp( name, "MultiLineString" )==0 )
+ return parse_geojson_multilinestring(geojson, hasz, root_srid);
+
+ if( strcasecmp( name, "MultiPolygon" )==0 )
+ return parse_geojson_multipolygon(geojson, hasz, root_srid);
+
+ if( strcasecmp( name, "GeometryCollection" )==0 )
+ return parse_geojson_geometrycollection(geojson, hasz, root_srid);
+
+ lwerror("invalid GeoJson representation");
+ return NULL; /* Never reach */
+}
+#endif /* HAVE_LIBJSON */
+
+PG_FUNCTION_INFO_V1(geom_from_geojson);
+Datum geom_from_geojson(PG_FUNCTION_ARGS)
+{
+#ifndef HAVE_LIBJSON
+ elog(ERROR, "You need JSON-C for ST_GeomFromGeoJSON");
+ PG_RETURN_NULL();
+#else /* HAVE_LIBJSON */
+
+ GSERIALIZED *geom;
+ LWGEOM *lwgeom;
+ text *geojson_input;
+ int geojson_size;
+ char *geojson;
+ int root_srid=0;
+ bool hasz=true;
+ json_tokener* jstok = NULL;
+ json_object* poObj = NULL;
+ json_object* poObjSrs = NULL;
+
+ /* Get the geojson stream */
+ if (PG_ARGISNULL(0)) PG_RETURN_NULL();
+ geojson_input = PG_GETARG_TEXT_P(0);
+ geojson = text2cstring(geojson_input);
+ geojson_size = VARSIZE(geojson_input) - VARHDRSZ;
+
+ /* Begin to Parse json */
+ jstok = json_tokener_new();
+ poObj = json_tokener_parse_ex(jstok, geojson, -1);
+ if( jstok->err != json_tokener_success)
+ {
+ char *err;
+ err += sprintf(err, "%s (at offset %d)", json_tokener_errors[jstok->err], jstok->char_offset);
+ json_tokener_free(jstok);
+ geojson_lwerror(err, 1);
+ }
+ json_tokener_free(jstok);
+
+ poObjSrs = findMemberByName( poObj, "crs" );
+ if (poObjSrs != NULL)
+ {
+ json_object* poObjSrsType = findMemberByName( poObjSrs, "type" );
+ if (poObjSrsType != NULL)
+ {
+ json_object* poObjSrsProps = findMemberByName( poObjSrs, "properties" );
+ json_object* poNameURL = findMemberByName( poObjSrsProps, "name" );
+ const char* pszName = json_object_get_string( poNameURL );
+ root_srid = getSRIDbySRS(pszName);
+ POSTGIS_DEBUGF(3, "getSRIDbySRS returned root_srid = %d.", root_srid );
+ }
+ }
+
+ lwgeom = parse_geojson(poObj, &hasz, &root_srid);
+
+ lwgeom_add_bbox(lwgeom);
+ if (root_srid && lwgeom->srid == -1) lwgeom->srid = root_srid;
+
+ if (!hasz)
+ {
+ LWGEOM *tmp = lwgeom_force_2d(lwgeom);
+ lwgeom_free(lwgeom);
+ lwgeom = tmp;
+
+ POSTGIS_DEBUG(2, "geom_from_geojson called.");
+ }
+
+ geom = geometry_serialize(lwgeom);
+ lwgeom_free(lwgeom);
+
+ PG_RETURN_POINTER(geom);
+#endif
+}
+
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