I have a Lealfet map in a Laravel Blade view where the user can draw shapes and markers. These features are registered in a GeoJson object, that I stringify and insert in a hidden textarea with name "geojson" to submit it to the server, within a form.
The problem is that I want to save this data as geometry type in my PostgreSQL database, using the PostGis ST_GeomFromGeoJSON() function, but I can't get it to work.
Here is what I tried for now:
$site = new Site;
$data = $request->all();
unset($data['geojson']);
foreach($data as $key=>$d)
{
$site->$key = $d;
}
$geojson = json_decode($request->geojson);
$site->save();
DB::update('update posha_sites set geom = ST_GeomFromGeoJSON(?)
WHERE num_site = ?
AND city_id = ?',
[$geojson, $request->num_site, $city_id->id]
);
Right now I am saving all my data and then trying to insert the geospatial data, as I don't know how I could use a raw query while saving the rest of my data.
When I do that I am getting this error:
Object of class stdClass could not be converted to string
Here is the whole migration for the posha_sites table:
public function up()
{
Schema::create('posha_sites', function (Blueprint $table) {
$table->bigIncrements('id');
$table->string('name');
$table->bigInteger('num_site');
$table->string('type', 50)->nullable();
$table->mediumText('adresse')->nullable();
$table->string('cartes_anciennes')->nullable();
$table->string('carte_topo')->nullable();
$table->mediumText('cadastre_remembre')->nullable();
$table->mediumText('cadastre_moderne')->nullable();
$table->mediumText('cadastre_ancien')->nullable();
$table->string('lieu_dit')->nullable();
$table->mediumText('nature_parcelles')->nullable();
$table->mediumText('conditions_acces')->nullable();
$table->string('situation_administrative')->nullable();
$table->string('altitude')->nullable();
$table->string('relief')->nullable();
$table->mediumText('hydrographie')->nullable();
$table->string('geologie')->nullable();
$table->string('vestiges_periode')->nullable();
$table->mediumText('vestiges_nature')->nullable();
$table->mediumText('vestiges_conservation')->nullable();
$table->longText('plans_documents_figures')->nullable();
$table->longText('sources_manuscrites')->nullable();
$table->longText('sources_imprimees')->nullable();
$table->longText('renseignement_oral')->nullable();
$table->longText('bibliographie')->nullable();
$table->longText('histoire')->nullable();
$table->longText('historiographie')->nullable();
$table->longText('description_histoire_monumentale')->nullable();
$table->geometrycollection('geom')->nullable();
$table->string('last_author')->nullable();
$table->integer('tree_id')->unsigned()->nullable();
$table->integer('parent_id')->unsigned()->nullable();
$table->integer('city_id')->unsigned();
$table->timestamps();
});
}
The function ST_GeomFromGeoJSON() is in fact expecting a string so I didn't decode my $geojson variable:
$geojson = $request->geojson;
instead of:
$geojson = json_decode($request->geojson);
But I still get an error:
SQLSTATE[XX000]: Internal error:
7 ERROR: invalid GeoJson representation (SQL: update posha_sites set geom = ST_GeomFromGeoJSON({"type":"FeatureCollection","features":[{"type":"Feature","properties":{},"geometry":{"type":"Point","coordinates":[-0.229114,44.564488]}}]}) WHERE num_site = 248 AND city_id = 5)
Yet I tested my geojson in an online geojson validator and it seems correct.
Assuming you have at least PostgreSQL version 9.3, you can use a few JSON functions and operators to extract the relevant parts of the GeoJSON specification required by ST_GeomFromGeoJSON to create geometries.
Try the following, where you can replace the JSON in the top part:
WITH data AS (SELECT '{ "type": "FeatureCollection",
"features": [
{ "type": "Feature",
"geometry": {"type": "Point", "coordinates": [102.0, 0.5]},
"properties": {"prop0": "value0"}
},
{ "type": "Feature",
"geometry": {
"type": "LineString",
"coordinates": [
[102.0, 0.0], [103.0, 1.0], [104.0, 0.0], [105.0, 1.0]
]
},
"properties": {
"prop0": "value0",
"prop1": 0.0
}
},
{ "type": "Feature",
"geometry": {
"type": "Polygon",
"coordinates": [
[ [100.0, 0.0], [101.0, 0.0], [101.0, 1.0],
[100.0, 1.0], [100.0, 0.0] ]
]
},
"properties": {
"prop0": "value0",
"prop1": {"this": "that"}
}
}
]
}'::json AS fc)
SELECT
row_number() OVER () AS gid,
ST_AsText(ST_GeomFromGeoJSON(feat->>'geometry')) AS geom,
feat->'properties' AS properties
FROM (
SELECT json_array_elements(fc->'features') AS feat
FROM data
) AS f;
Finds three geometries. The geom column has the geometry object, and the gid is the feature number. The ST_AsText function shows the WKT equivalent of each geometry. I've also included the properties or attributes that can be defined for each geometry, as is shown in the specification.
gid | geom | properties
-----+------------------------------------------+--------------------------------------
1 | POINT(102 0.5) | {"prop0": "value0"}
2 | LINESTRING(102 0,103 1,104 0,105 1) | { +
| | "prop0": "value0", +
| | "prop1": 0.0 +
| | }
3 | POLYGON((100 0,101 0,101 1,100 1,100 0)) | { +
| | "prop0": "value0", +
| | "prop1": {"this": "that"}+
| | }
(3 rows)
You should assign an SRID for the geometry, using ST_SetSRID.
Or if you simply need a single heterogeneous GEOMETRYCOLLECTION, you can make it compact like this:
SELECT ST_AsText(ST_Collect(ST_GeomFromGeoJSON(feat->>'geometry')))
FROM (
SELECT json_array_elements('{ ... put JSON here ... }'::json->'features') AS feat
) AS f;
GEOMETRYCOLLECTION(POINT(2565453.18267219 -3835048.65976031),LINESTRING(2727584.72197102 -3713449.19424187,2732476.69178127 -3992291.47342619),POLYGON((2442627.90254053 -3705499.95430853,2425506.00820465 -3886502.83728783,2555143.20817631 -3910962.68633909,2442627.90254053 -3705499.95430853)))
See also Creating GeoJSON Feature Collections with JSON and PostGIS functions from the Postgres OnLine Journal, which does the opposite.