CRON Server

index.js

// Modules
const cors = require('cors'),
	  cron = require('node-cron'),
	  express = require('express'),
	  expressStaticGzip = require("express-static-gzip"),
	  path = require('path'),
	  request = require('request'),
	  THREE = require('three'),
	  app = express(),
// Globals
	  url = "https://earthquake.usgs.gov/earthquakes/feed/v1.0/summary/",
	  urlSuffix = [
        "all_hour.geojson",
        "all_day.geojson",
        "all_week.geojson",
        "all_month.geojson"
	  ], 
	  quakes = {
	      "0": [],
		  "1": [],
		  "2": [],
		  "3": []
	  },
	  threeData = {
	  	"0": null,
	  	"1": null,
	  	"2": null,
	  	"3": null
	  }

// CORS for Local Testing
app.use(cors()); 

// Compression
app.use('/', expressStaticGzip(path.join(__dirname, 'build'), {
	enableBrotli: true,
	orderPreference: ['br', 'gz']
}))

// Routes
app.get('/', function(req, res) {
	res.sendFile(path.join(__dirname, 'build', 'index.html'))
})

app.get('/.well-known(/*)?', function(req, res) {
	res.sendFile(path.join(__dirname, '.well-known', 'assetlinks.json'))
})

app.get('/privacy-policy', function(req, res) {
	res.sendFile(path.join(__dirname, 'privacy_policy.html'))
})

// API
app.get('/quakes/:index', function(req, res){
	res.setHeader('Content-Type', 'application/json');
    req.params.index != "all" ? res.json(quakes[req.params.index]) : res.json(quakes);
});

app.get('/threeData/:index', function(req, res){
	res.setHeader('Content-Type', 'application/json');
    req.params.index != "all" ? res.json(threeData[req.params.index]) : res.json(threeData);
});

app.get('/quakeData/:index', function(req, res){
	// Send Specific Selection or All
	const jsonArr = req.params.index != "all" ? [
		quakes[req.params.index],
		threeData[req.params.index]
	] : [
		quakes,
		threeData
	]
	
	res.setHeader('Content-Type', 'application/json');
	res.json(jsonArr);
});

// Cron every minute
cron.schedule('*/1 * * * *', () => {

	console.log("CRON JOB - "+new Date().getMinutes());

	// Loop over API urls, make AJAX reqs, store in global
	for (let i = 0; i < urlSuffix.length; i++) {
		request(url+urlSuffix[i], function (error, response, body) {	

			if (response.statusCode == 200) {
				const parsedBody = JSON.parse(body),
					  quakeArr = new Array(parsedBody.metadata.count),
					  geom = new THREE.Geometry(),
            		  cubeMat = new THREE.MeshBasicMaterial({ vertexColors: true });

				// Data Parsing
			    for (const feature of parsedBody.features) {
			    		  // Quake Obj
			        const magnitude = feature.properties.mag,
			              location = feature.properties.place,
			              time = feature.properties.time,
			              coordinates = feature.geometry.coordinates,
			              quake = {
			                  "magnitude": magnitude,
			                  "location": location,
			                  "time": time,
			                  "coordinates": coordinates
			              },
			              // Three Data Obj
			              quakeVector = longLatToSphere(coordinates[0], coordinates[1], 600),
			              rgb = colorData(magnitude),
			              cubeColor = new THREE.Color(rgb),
			              cubeHeight = magnitude > 0 ? (magnitude ** 3) * 1.75 : 0,
			              cubeGeom = new THREE.BoxGeometry(3, 3, cubeHeight, 1, 1, 1),
                  		  cube = new THREE.Mesh(cubeGeom, cubeMat);

                  	// set position of cube on globe, point to center, merge together for one draw call
		            for ( let j = 0; j < cubeGeom.faces.length; j ++ ) {
		                cubeGeom.faces[j].color = cubeColor;
		            }

		            cube.position.set(quakeVector.x, quakeVector.y, quakeVector.z);
		            cube.lookAt(new THREE.Vector3(0,0,0));
		            cube.updateMatrix();
		            geom.merge(cube.geometry, cube.matrix);

			        quakeArr.push(quake);
			    }

			    // Data Sorting by Highest Magnitude
			    quakeArr.sort((a, b) => b.magnitude - a.magnitude);
			    // Store in Global
				quakes[i] = quakeArr;
				threeData[i] = geom;
			} else {
				console.log(response);
				console.log("error: "+response);
				console.log(this);
			}

		})
	}

})

// Three.js Viz Functions

// Intensity Coloring
colorData = percentage => {
	let rgbString = "",
	    r = parseInt(percentage * 25.5),
	    g = 255 - r;

	r = r < 0 ? 0 : r;
	rgbString = `rgb(${r},${g}, 0)`;
	return rgbString;
}

// Projection Mapping
longLatToSphere = (long, lat, radius) => {
	const phi   = (90-lat)*(Math.PI/180),
	      theta = (long+180)*(Math.PI/180),
	      x = -((radius) * Math.sin(phi)*Math.cos(theta)),
	      z = ((radius) * Math.sin(phi)*Math.sin(theta)),
	      y = ((radius) * Math.cos(phi));

	return new THREE.Vector3(x,y,z);
}

// Listen
app.listen(8080, () => console.log("Static client listening on 8080"))