sabman/index.html

## index.html
<!DOCTYPE html>
<html>
  <head>
    <title>leaflet.draw +  CARTO</title>
    <meta name="viewport" content="initial-scale=1.0, user-scalable=no" />
    <meta http-equiv="content-type" content="text/html; charset=UTF-8"/>
    <link rel="shortcut icon" href="https://cartodb.com/assets/favicon.ico" />

    <script src="https://cdnjs.cloudflare.com/ajax/libs/leaflet/1.3.1/leaflet-src.js"></script>

    <link rel="stylesheet" href="https://libs.cartocdn.com/cartodb.js/v3/3.15/themes/css/cartodb.css" />
    <script src="https://libs.cartocdn.com/cartodb.js/v3/3.15/cartodb.js"></script>


    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/leaflet.draw/0.4.3/leaflet.draw.css" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/leaflet.draw/0.4.3/leaflet.draw.js"></script>

    <style>
      html, body, #map {
        height: 100%;
        padding: 0;
        margin: 0;
      }
      #infobox{
        width: 200px;
        height: 200px;
        position: absolute;
        top: 20px;
        left: 20px;
        background-color: white;
        opacity: 0.6;
        text-align: center;
        font-family: "Open Sans";
      }
    </style>

  </head>
  <body>

    <!-- map div -->
    <div id="map"></div>

    <!-- infobox div -->
    <div id="infobox">
      <h4>Draw a geometry</h4>
      <p id="count">Count</p>
      <p id="total">Total</p>
      <p id="avg">Average</p
    </div>

    <script type="text/cartocss" id="style">
      #layer {
        marker-width: 7;
        marker-fill: #EE4D5A;
        marker-fill-opacity: 0.9;
        marker-line-color: #FFFFFF;
        marker-line-width: 1;
        marker-line-opacity: 1;
        marker-type: ellipse;
        marker-allow-overlap: true;
      }
    </script>

    <script type="text/sql" id="query">
      SELECT
        a.*
      FROM
        populated_places a
    </script>

    <script>
      function main() {

        // get styles & query
          const style = $("#style").text(),
              query = $("#query").text(),

        // declare map variable
              map = L.map('map', {
                  zoomControl: false,
                  center: [41, -15],
                  zoom: 3
                  });

        // add basemap
        L.tileLayer('https://{s}.basemaps.cartocdn.com/rastertiles/voyager_nolabels/{z}/{x}/{y}.png', {attribution: '&copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors, &copy; <a href="https://cartodb.com/attributions">CARTO</a>'}).addTo(map);

        //prep the draw FeatureGroup and add Leaflet.draw controls to map
        const editableLayers = new L.FeatureGroup();
        map.addLayer(editableLayers);

        const drawPluginOptions = {
          position: 'topright',
          draw: {
            polygon: {
              allowIntersection: false,
              drawError: {
                color: '#46945C',
                message: '<strong>Oh snap!<strong> you can\'t draw that!'
              },
              shapeOptions: {
                color: '#826DBA'
              }
            },

            polyline: false,
            circle: false,
            rectangle: false,
            marker: false,
            },
          edit: {
            featureGroup: editableLayers,
            remove: false
          }
        };

        const drawControl = new L.Control.Draw(drawPluginOptions);
        map.addControl(drawControl);

        // add CARTO layer
        cartodb.createLayer(map, {
          user_name: 'ramirocartodb',
          type: 'cartodb',
          sublayers: [{
            sql: query,
            cartocss: style
          }]
        }).addTo(map)
        .done(function(layer){

          // declare sublayer variable
          const cityLayer = layer.getSubLayer(0);

          // draw layer, intersect with CARTO layer & get count, total & avg data
          map.on('draw:created', function(e) {

              // draw layer
              const drawLayer = e.layer;
              editableLayers.addLayer(drawLayer);

              // get geojson from the draw layer
              const geojson = drawLayer.toGeoJSON(),
                    geom = JSON.stringify(geojson["geometry"]),

              // set new query & style for intersected geometries
                    new_query = query + ` WHERE ST_Intersects(ST_SetSRID(ST_GeomFromGeoJSON('${geom}'), 4326), a.the_geom)`;
              cityLayer.setSQL(new_query);
              cityLayer.setCartoCSS('#layer {marker-width: 7; marker-fill: #FFFFFF; marker-fill-opacity: 0.9; marker-line-color: #EE4D5A; marker-line-width: 1; marker-line-opacity: 1; marker-type: ellipse; marker-allow-overlap: true;}');

              // get count, total and avg from intersected geometries
              const sql = new cartodb.SQL({ user: 'ramirocartodb' }),

                    widget_query = `SELECT count(a.*) as count, sum(a.pop_max) as total, avg(a.pop_max) as avg FROM populated_places a WHERE ST_Intersects(ST_SetSRID(ST_GeomFromGeoJSON('${geom}'), 4326), a.the_geom)`;

              sql.execute(widget_query)
                .done(function(data) {

                  const count = JSON.stringify(data.rows[0].count),
                        total = JSON.stringify(data.rows[0].total),
                        avg = JSON.stringify(data.rows[0].avg);

                  // return count, total and avg in the infobox
                  $('#count').text(count);
                  $('#total').text(total);
                  $('#avg').text(avg);

                })
                .error(function(errors) {
                  // errors contains a list of errors
                  console.log("errors:" + errors);
              })

              // remove editable layer and clear parameters from the infobox when clicking on the draw layer
              drawLayer.on('click', function(e){
                editableLayers.clearLayers(e.layer);
                cityLayer.setSQL(query);
                cityLayer.setCartoCSS(style);

                // clear parameters from the infobox
                $('#count').text('Count');
                $('#total').text('Total');
                $('#avg').text('Average');

              });

          });

        });

      }
    window.onload = main;
    </script>

  </body>
</html>
	<!DOCTYPE html>
	<html>
	<head>
	<title>leaflet.draw + CARTO</title>
	<meta name="viewport" content="initial-scale=1.0, user-scalable=no" />
	<meta http-equiv="content-type" content="text/html; charset=UTF-8"/>
	<link rel="shortcut icon" href="https://cartodb.com/assets/favicon.ico" />

	<script src="https://cdnjs.cloudflare.com/ajax/libs/leaflet/1.3.1/leaflet-src.js"></script>

	<link rel="stylesheet" href="https://libs.cartocdn.com/cartodb.js/v3/3.15/themes/css/cartodb.css" />
	<script src="https://libs.cartocdn.com/cartodb.js/v3/3.15/cartodb.js"></script>


	<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/leaflet.draw/0.4.3/leaflet.draw.css" />
	<script src="https://cdnjs.cloudflare.com/ajax/libs/leaflet.draw/0.4.3/leaflet.draw.js"></script>

	<style>
	html, body, #map {
	height: 100%;
	padding: 0;
	margin: 0;
	}
	#infobox{
	width: 200px;
	height: 200px;
	position: absolute;
	top: 20px;
	left: 20px;
	background-color: white;
	opacity: 0.6;
	text-align: center;
	font-family: "Open Sans";
	}
	</style>

	</head>
	<body>

	<!-- map div -->
	<div id="map"></div>

	<!-- infobox div -->
	<div id="infobox">
	<h4>Draw a geometry</h4>
	<p id="count">Count</p>
	<p id="total">Total</p>
	<p id="avg">Average</p
	</div>

	<script type="text/cartocss" id="style">
	#layer {
	marker-width: 7;
	marker-fill: #EE4D5A;
	marker-fill-opacity: 0.9;
	marker-line-color: #FFFFFF;
	marker-line-width: 1;
	marker-line-opacity: 1;
	marker-type: ellipse;
	marker-allow-overlap: true;
	}
	</script>

	<script type="text/sql" id="query">
	SELECT
	a.*
	FROM
	populated_places a
	</script>

	<script>
	function main() {

	// get styles & query
	const style = $("#style").text(),
	query = $("#query").text(),

	// declare map variable
	map = L.map('map', {
	zoomControl: false,
	center: [41, -15],
	zoom: 3
	});

	// add basemap
	L.tileLayer('https://{s}.basemaps.cartocdn.com/rastertiles/voyager_nolabels/{z}/{x}/{y}.png', {attribution: '© <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors, © <a href="https://cartodb.com/attributions">CARTO</a>'}).addTo(map);

	//prep the draw FeatureGroup and add Leaflet.draw controls to map
	const editableLayers = new L.FeatureGroup();
	map.addLayer(editableLayers);

	const drawPluginOptions = {
	position: 'topright',
	draw: {
	polygon: {
	allowIntersection: false,
	drawError: {
	color: '#46945C',
	message: '<strong>Oh snap!<strong> you can\'t draw that!'
	},
	shapeOptions: {
	color: '#826DBA'
	}
	},

	polyline: false,
	circle: false,
	rectangle: false,
	marker: false,
	},
	edit: {
	featureGroup: editableLayers,
	remove: false
	}
	};

	const drawControl = new L.Control.Draw(drawPluginOptions);
	map.addControl(drawControl);

	// add CARTO layer
	cartodb.createLayer(map, {
	user_name: 'ramirocartodb',
	type: 'cartodb',
	sublayers: [{
	sql: query,
	cartocss: style
	}]
	}).addTo(map)
	.done(function(layer){

	// declare sublayer variable
	const cityLayer = layer.getSubLayer(0);

	// draw layer, intersect with CARTO layer & get count, total & avg data
	map.on('draw:created', function(e) {

	// draw layer
	const drawLayer = e.layer;
	editableLayers.addLayer(drawLayer);

	// get geojson from the draw layer
	const geojson = drawLayer.toGeoJSON(),
	geom = JSON.stringify(geojson["geometry"]),

	// set new query & style for intersected geometries
	new_query = query + ` WHERE ST_Intersects(ST_SetSRID(ST_GeomFromGeoJSON('${geom}'), 4326), a.the_geom)`;
	cityLayer.setSQL(new_query);
	cityLayer.setCartoCSS('#layer {marker-width: 7; marker-fill: #FFFFFF; marker-fill-opacity: 0.9; marker-line-color: #EE4D5A; marker-line-width: 1; marker-line-opacity: 1; marker-type: ellipse; marker-allow-overlap: true;}');

	// get count, total and avg from intersected geometries
	const sql = new cartodb.SQL({ user: 'ramirocartodb' }),

	widget_query = `SELECT count(a.*) as count, sum(a.pop_max) as total, avg(a.pop_max) as avg FROM populated_places a WHERE ST_Intersects(ST_SetSRID(ST_GeomFromGeoJSON('${geom}'), 4326), a.the_geom)`;

	sql.execute(widget_query)
	.done(function(data) {

	const count = JSON.stringify(data.rows[0].count),
	total = JSON.stringify(data.rows[0].total),
	avg = JSON.stringify(data.rows[0].avg);

	// return count, total and avg in the infobox
	$('#count').text(count);
	$('#total').text(total);
	$('#avg').text(avg);

	})
	.error(function(errors) {
	// errors contains a list of errors
	console.log("errors:" + errors);
	})

	// remove editable layer and clear parameters from the infobox when clicking on the draw layer
	drawLayer.on('click', function(e){
	editableLayers.clearLayers(e.layer);
	cityLayer.setSQL(query);
	cityLayer.setCartoCSS(style);

	// clear parameters from the infobox
	$('#count').text('Count');
	$('#total').text('Total');
	$('#avg').text('Average');

	});

	});

	});

	}
	window.onload = main;
	</script>

	</body>
	</html>