Add endpoint for retrieving real-time data as GeoJSON

lib/www/server/api/index.js

@@ -134,6 +134,9 @@ app.map({
 // 	},
 	'/navdata/': {
 		get: [ mw.navdata.get ],
+		'gis/:featuretype(line|point)': {
+			get: [ mw.gis.navdata.get ]
+		}
 	}
 //
 // 	'/user': {

lib/www/server/api/middleware/gis/index.js

@@ -1,3 +1,4 @@
 module.exports = {
-	project: require('./project')
+	project: require('./project'),
+	navdata: require('./navdata')
 };

lib/www/server/api/middleware/gis/navdata/get.js

@@ -0,0 +1,40 @@
+
+const { gis } = require('../../../../lib/db');
+
+function makeOptions (query) {
+	const options = {};
+
+	if (query.hasOwnProperty("limit")) {
+		options.limit = Math.abs(Number(query.limit));
+	}
+
+	if (query.hasOwnProperty("bbox")) {
+		options.bbox = query.bbox
+			.split(",")
+			.slice(0, 4)
+			.map( (n, i) => (i % 2) ? Number(n) % 90 : Number(n) % 180 );
+
+		if (options.bbox.some(n => isNaN(n))) {
+			delete options.bbox;
+		}
+	}
+
+	return options;
+}
+
+module.exports = async function (req, res, next) {
+
+	const handler = req.params.featuretype == "point"
+		? gis.navdata.get.points
+		: gis.navdata.get.lines;
+
+	const options = makeOptions(req.query);
+
+	try {
+		res.status(200).send(await handler(options));
+		next();
+	} catch (err) {
+		next(err);
+	}
+
+};

lib/www/server/api/middleware/gis/navdata/index.js

@@ -0,0 +1,3 @@
+module.exports = {
+	get: require('./get')
+};

lib/www/server/lib/db/gis/index.js

@@ -1,5 +1,6 @@
 
 module.exports = {
 	project: require('./project'),
+	navdata: require('./navdata')
 // 	line: require('./line')
 };

lib/www/server/lib/db/gis/navdata/get.js

@@ -0,0 +1,83 @@
+ 
+
+const { pool } = require('../../connection');
+
+async function lines (options = {}) {
+
+	const client = await pool.connect();
+
+	const text = `
+		SELECT ST_AsGeoJSON(ST_MakeLine(geometry)) geojson
+		FROM (
+			SELECT geometry
+			FROM real_time_inputs
+			WHERE
+				($1 IS true
+					AND geometry && ST_MakeEnvelope($2, $3, $4, $5, 4326)
+				)
+				OR ($1 IS false AND true)
+			ORDER BY tstamp DESC
+			LIMIT $6
+		) t
+	`;
+
+// 	const values = [ options.limit || 1000, opts.offset || 0 ];
+	const values = [
+		"bbox" in options,
+		...(options.bbox||[null, null, null, null]),
+		options.limit || 5000
+	];
+
+	const res = await client.query(text, values);
+	client.release();
+
+	if (res.rows && res.rows.length) {
+		return res.rows.map(r => JSON.parse(r.geojson));
+	} else {
+		throw {status: 404};
+	}
+}
+
+async function points (options = {}) {
+
+	const client = await pool.connect();
+
+	const values = [
+		"bbox" in options,
+		...(options.bbox||[null, null, null, null]),
+		options.limit || 5000
+	];
+
+	const text = `
+		SELECT json_build_object(
+			'type', 'Feature',
+			'geometry', ST_AsGeoJSON(s.geometry)::json,
+			'properties', s.meta
+		) geojson
+		FROM (
+			SELECT geometry, meta
+			FROM real_time_inputs
+			WHERE
+				($1 IS true
+					AND geometry && ST_MakeEnvelope($2, $3, $4, $5, 4326)
+				)
+				OR ($1 IS false AND true)
+			ORDER BY tstamp DESC
+			LIMIT $6
+		) s;
+	`;
+
+	const res = await client.query(text, values);
+	client.release();
+
+	if (res.rows && res.rows.length) {
+		return res.rows.map(r => r.geojson);
+	} else {
+		throw {status: 404};
+	}
+}
+
+module.exports = {
+	lines,
+	points
+};

lib/www/server/lib/db/gis/navdata/index.js

@@ -0,0 +1,4 @@
+
+module.exports = {
+	get: require('./get'),
+};