How to output geoJSON file from mysql spatial table? - mysql

Question

I have a mysql spatial database ('mydb1') of one table ('pk'), that i obtained from a point shapefile using ogr2ogr tool. one row of this 'pk' table, is like:
OGR_FID SHAPE CODIF Position_X Position_Y Nom Status
1 [GEOMETRY-25o] PAC182854 398235.38 414569.24 G-31 Vert
I need to output the geoJSON file of this table. I downloaded geoPHP library and used MySQL to GeoJSON script which i adapted to my settings, like below:
<?php
/**
* Title: MySQL to GeoJSON (Requires https://github.com/phayes/geoPHP)
* Notes: Query a MySQL table or view and return the results in GeoJSON format, suitable for use in OpenLayers, Leaflet, etc.
* Author: Bryan R. McBride, GISP
* Contact: bryanmcbride.com
* GitHub: https://github.com/bmcbride/PHP-Database-GeoJSON
*/
# Include required geoPHP library and define wkb_to_json function
include_once('geoPHP/geoPHP.inc');
function wkb_to_json($wkb) {
$geom = geoPHP::load($wkb,'wkb');
return $geom->out('json');
}
# Connect to MySQL database
$conn = new PDO('mysql:host=localhost;dbname=mydb1','root','admin');
# Build SQL SELECT statement and return the geometry as a WKB element
$sql = 'SELECT *, AsWKB(SHAPE) AS wkb FROM pk';
# Try query or error
$rs = $conn->query($sql);
if (!$rs) {
echo 'An SQL error occured.\n';
exit;
}
# Build GeoJSON feature collection array
$geojson = array(
'type' => 'FeatureCollection',
'features' => array()
);
# Loop through rows to build feature arrays
while ($row = $rs->fetch(PDO::FETCH_ASSOC)) {
$properties = $row;
# Remove wkb and geometry fields from properties
unset($properties['wkb']);
unset($properties['SHAPE']);
$feature = array(
'type' => 'Feature',
'geometry' => json_decode(wkb_to_json($row['wkb'])),
'properties' => $properties
);
# Add feature arrays to feature collection array
array_push($geojson['features'], $feature);
}
header('Content-type: application/json');
echo json_encode($geojson, JSON_NUMERIC_CHECK);
$conn = NULL;
?>
But when i execute the code on the browser, i get totally a blank page. What's wrong should i fix to output my geoJSON file plz?

Answer 1

You should check the php logs for more information in case an error ocured. Make sure error reporting and display are enabled:
error_reporting(E_ALL);
ini_set('display_errors', 1);
if no error show up inspect the $geojson object easiest would be using
print_r($geojson);