Moved the nodejs agent to its own subfolder to make room for my haskell agent

5 files changed, 460 insertions, 0 deletions

diff --git a/nodejs/lib/api.js b/nodejs/lib/api.js
new file mode 100644
index 0000000..667ef37
--- /dev/null
+++ b/nodejs/lib/api.js
@@ -0,0 +1,140 @@
+import * as fs from 'fs';
+import * as events from 'events';
+
+import { getToken } from '../database/config.js';
+import { PriorityQueue } from './priority_queue.js';
+
+// queue processor module variables
+const bus = new events.EventEmitter(); // a bus to notify the queue processor to start processing messages
+let busy = false; // true if we are already sending api requests.
+let backoffSeconds = 0;
+let running = false;
+// other module variables
+let headers = undefined; // a file scope variable so that we only evaluate these once.
+let queue = new PriorityQueue(); // a priority queue to hold api calls we want to send, allows for throttling.
+
+// a single queue processor should be running at any time, otherwise there will be trouble!
+async function queue_processor() {
+	if (running) {
+		throw 'refusing to start a second queue processor';
+	}
+	running = true;
+	while(true) {
+		try {
+			if (backoffSeconds > 0) {
+				await sleep(backoffSeconds * 1000);
+				backoffSeconds = 0;
+			}
+			if (queue.isEmpty()) {
+				busy = false;
+				await new Promise(resolve => bus.once('send', resolve));
+				busy = true;
+			}
+			const before = new Date();
+			await send_this(queue.dequeue().element);
+			const duration = new Date() - before;
+			if (duration < 400) { // 333 should work, but 400 should still allow some manual requests to go through during development
+				await sleep(400 - duration);
+			}
+		} catch (e) {
+			running = false;
+			throw e;
+		}
+	}
+}
+queue_processor();
+
+// send takes a request object as argument and an optional context ctx
+// example request: {
+//    endpoint: the path part of the url to call,
+//    method: HTTP method for `fetch` call, defaults to 'GET',
+//    payload: optional json object that will be send along with the request,
+//    priority: optional priority value (defaults to 10, lower than 10 means the message will be sent faster)
+// }
+export function send(request, ctx) {
+	return new Promise((resolve, reject) => {
+		let data = {
+			ctx: ctx,
+			reject: reject,
+			request: request,
+			resolve: resolve,
+		};
+		queue.enqueue(data, request.priority ? request.priority : 10);
+		if (!busy) {
+			bus.emit('send'); // the queue was previously empty, let's wake up the queue_processor
+		}
+	});
+}
+
+// send_this take a data object as argument built in the send function above
+async function send_this(data) {
+	if (headers === undefined) {
+		const token = getToken();
+		if (token === null) {
+			throw 'Could not get token from the database. Did you init or register yet?';
+		}
+		headers = {
+			'Content-Type': 'application/json',
+			'Authorization': `Bearer ${token}`
+		};
+	}
+	let options = {
+		headers: headers,
+	};
+	if (data.request.method !== undefined) {
+		options['method'] = data.request.method;
+	}
+	if (data.request.payload !== undefined) {
+		options['body'] = JSON.stringify(data.request.payload);
+	}
+	fs.writeFileSync('log', JSON.stringify({event: 'send', date: new Date(), data: data}) + '\n', {flag: 'a+'});
+	try {
+		let response = await fetch(`https://api.spacetraders.io/v2${data.request.endpoint}`, options);
+		response = await response.json();
+		switch(response.error?.code) {
+			//case 401: // TODO 401 means a server reset happened
+			// TODO reject all promises in queue
+			// close database file
+			// rm database file
+			// logrotate
+			// spawnSync
+			// break;
+		case 429:  // 429 means rate limited, let's hold back as instructed
+			backoffSeconds = response.error.data.retryAfter;
+			queue.enqueue(data, 1);
+			break;
+		case 503:  // 503 means maintenance mode, let's hold back for 1 minute
+			backoffSeconds = 60;
+			queue.enqueue(data, 1);
+			break;
+		default: // no error!
+			fs.writeFileSync('log', JSON.stringify({event: 'response', date: new Date(), data: response}) + '\n', {flag: 'a+'});
+			return data.resolve(response);
+		}
+	} catch (err) {
+		fs.writeFileSync('log', JSON.stringify({event: 'error', date: new Date(), data: err}) + '\n', {flag: 'a+'});
+		switch(err.cause?.code) {
+		case 'EAI_AGAIN': // DNS lookup timed out error, let's hold back for 5 seconds
+			backoffSeconds = 5;
+			queue.enqueue(data, 1);
+			break;
+		case 'ECONNRESET':
+			queue.enqueue(data, 1);
+			break;
+		case 'UND_ERR_CONNECT_TIMEOUT':
+			queue.enqueue(data, 1);
+			break;
+		default:
+			data.reject(response);
+		}
+	}
+}
+
+export function debugLog(ctx) {
+	console.log(`--- ${Date()} -----------------------------------------------------------------------------`);
+	console.log(JSON.stringify(ctx, null, 2));
+}
+
+export function sleep(delay) {
+	return new Promise((resolve) => setTimeout(resolve, delay))
+}
diff --git a/nodejs/lib/contracts.js b/nodejs/lib/contracts.js
new file mode 100644
index 0000000..316e181
--- /dev/null
+++ b/nodejs/lib/contracts.js
@@ -0,0 +1,26 @@
+import * as api from './api.js';
+import * as dbShips from '../database/ships.js';
+
+export async function accept(ctx) {
+	return await api.send({endpoint: `/my/contracts/${ctx.contract}/accept`, method: 'POST'});
+}
+
+export async function contracts() {
+	return await api.send({endpoint: '/my/contracts'});
+}
+
+export async function deliver(ctx) {
+	const response = await api.send({ endpoint: `/my/contracts/${ctx.contract}/deliver`, method: 'POST', payload: {
+		shipSymbol: ctx.symbol,
+		tradeSymbol: ctx.good,
+		units: ctx.units,
+	}});
+	if (response.error !== undefined) {
+		throw response;
+	}
+	dbShips.setShipCargo(ctx.symbol, response.data.cargo);
+}
+
+export async function fulfill(ctx) {
+	return await api.send({ endpoint: `/my/contracts/${ctx.contract}/fulfill`, method: 'POST'});
+}
diff --git a/nodejs/lib/priority_queue.js b/nodejs/lib/priority_queue.js
new file mode 100644
index 0000000..da526b2
--- /dev/null
+++ b/nodejs/lib/priority_queue.js
@@ -0,0 +1,39 @@
+export class QElement {
+	constructor(element, priority) {
+		this.element = element;
+		this.priority = priority;
+	}
+}
+
+export class PriorityQueue {
+	constructor(elt) {
+		this.items = [];
+		if (elt !== undefined) {
+			this.enqueue(elt, 0);
+		}
+	}
+
+	enqueue(element, priority) {
+		let qElement = new QElement(element, priority);
+
+		for (let i = 0; i < this.items.length; ++i) {
+			if (this.items[i].priority > qElement.priority) {
+				this.items.splice(i, 0, qElement);
+				return;
+			}
+		}
+		this.items.push(qElement);
+	}
+	dequeue() {
+		return this.items.shift(); // we would use pop to get the highest priority, shift() gives us the lowest priority
+	}
+	front() {
+		return this.items[0];
+	}
+	rear() {
+		return this.items[this.items.length - 1];
+	}
+	isEmpty() {
+		return this.items.length === 0;
+	}
+}
diff --git a/nodejs/lib/ships.js b/nodejs/lib/ships.js
new file mode 100644
index 0000000..d75d78e
--- /dev/null
+++ b/nodejs/lib/ships.js
@@ -0,0 +1,187 @@
+import * as api from './api.js';
+import * as dbConfig from '../database/config.js';
+import * as dbShips from '../database/ships.js';
+import * as dbSurveys from '../database/surveys.js';
+import * as systems from '../lib/systems.js';
+
+export async function extract(ctx) {
+	const ship = dbShips.getShip(ctx.symbol);
+	const asteroidFields = await systems.type({symbol: ship.nav.systemSymbol, type: 'ASTEROID_FIELD'});
+	// TODO if there are multiple fields, find the closest one?
+	await navigate({symbol: ctx.symbol, waypoint: asteroidFields[0].symbol});
+	await orbit(ctx);
+	// TODO handle surveying?
+	const response = await api.send({endpoint: `/my/ships/${ctx.symbol}/extract`, method: 'POST'});
+	if (response.error !== undefined) {
+		switch(response.error.code) {
+		case 4000: // ship is on cooldown
+			await api.sleep(response.error.data.cooldown.remainingSeconds  * 1000);
+			return await extract(ctx);
+		case 4228: // ship is full
+			return null;
+		default: // yet unhandled error
+			throw response;
+		}
+	} else {
+		dbShips.setShipCargo(ctx.symbol, response.data.cargo);
+		await api.sleep(response.data.cooldown.remainingSeconds*1000);
+	}
+	return response;
+}
+
+export async function dock(ctx) {
+	const ship = dbShips.getShip(ctx.symbol);
+	if (ship.nav.status === 'DOCKED') {
+		return null;
+	}
+	const response = await api.send({endpoint: `/my/ships/${ctx.symbol}/dock`, method: 'POST'});
+	if (response.error !== undefined) {
+		switch(response.error.code) {
+		case 4214: // ship is in transit
+			await api.sleep(response.error.data.secondsToArrival  * 1000);
+			return await dock(ctx);
+		default: // yet unhandled error
+			throw response;
+		}
+	}
+	dbShips.setShipNav(ctx.symbol, response.data.nav);
+	return response;
+}
+
+function hasMount(shipSymbol, mountSymbol) {
+	const ship = dbShips.getShip(shipSymbol);
+	return ship.mounts.filter(s => s.symbol === mountSymbol).length > 0;
+}
+
+export async function jump(ctx) {
+	// TODO
+	const response = await api.send({endpoint: `/my/ships/${ctx.ship}/jump`, method: 'POST', payload: { systemSymbol: ctx.system }});
+	await api.sleep(response.data.cooldown.remainingSeconds*1000);
+	return response;
+}
+
+export async function navigate(ctx) {
+	const ship = dbShips.getShip(ctx.symbol);
+	if (ship.nav.waypointSymbol === ctx.waypoint) {
+		return await orbit(ctx);
+	}
+	await orbit(ctx);
+	// TODO if we do not have enough fuel, make a stop to refuel along the way or drift to the destination
+	const response = await api.send({endpoint: `/my/ships/${ctx.symbol}/navigate`, method: 'POST', payload: { waypointSymbol: ctx.waypoint }});
+	if (response.error !== undefined) {
+		switch(response.error.code) {
+		case 4214: // ship is in transit
+			await api.sleep(response.error.data.secondsToArrival  * 1000);
+			return await navigate(ctx);
+		default: // yet unhandled error
+			throw response;
+		}
+	}
+	dbShips.setShipFuel(ctx.symbol, response.data.fuel);
+	dbShips.setShipNav(ctx.symbol, response.data.nav);
+	const delay = new Date(response.data.nav.route.arrival) - new Date();
+	await api.sleep(delay);
+	response.data.nav.status = 'IN_ORBIT';
+	dbShips.setShipNav(ctx.symbol, response.data.nav);
+	await refuel(ctx);
+	return response;
+}
+
+export async function negotiate(ctx) {
+	// TODO
+	return await api.send({endpoint: `/my/ships/${ctx.ship}/negotiate/contract`, method: 'POST'});
+}
+
+export async function orbit(ctx) {
+	const ship = dbShips.getShip(ctx.symbol);
+	if (ship.nav.status === 'IN_ORBIT') {
+		return null;
+	}
+	const response = await api.send({endpoint: `/my/ships/${ctx.symbol}/orbit`, method: 'POST'});
+	if (response.error !== undefined) {
+		switch(response.error.code) {
+		case 4214: // ship is in transit
+			await api.sleep(response.error.data.secondsToArrival  * 1000);
+			return await orbit(ctx);
+		default: // yet unhandled error
+			throw response;
+		}
+	}
+	dbShips.setShipNav(ctx.symbol, response.data.nav);
+	return response;
+}
+
+export async function purchase(ctx) {
+	const response = await api.send({endpoint: '/my/ships', method: 'POST', payload: {
+		shipType: ctx.shipType,
+		waypointSymbol: ctx.waypoint,
+	}});
+	if (response.error !== undefined) {
+		throw response;
+	}
+	dbShips.setShip(response.data.ship);
+	return response.data;
+}
+
+export async function refuel(ctx) {
+	const ship = dbShips.getShip(ctx.symbol);
+	if (ship.fuel.current >= ship.fuel.capacity * 0.9) {
+		return null;
+	}
+	// TODO check if our current waypoint has a marketplace (and sells fuel)?
+	await dock(ctx);
+	const response = await api.send({endpoint: `/my/ships/${ctx.symbol}/refuel`, method: 'POST'});
+	if (response.error !== undefined) {
+		throw response;
+	}
+	dbShips.setShipFuel(ctx.symbol, response.data.fuel);
+	// TODO track credits
+	return response;
+}
+
+export async function sell(ctx) {
+	// TODO check if our current waypoint has a marketplace (and sells fuel)?
+	await dock(ctx);
+	const ship = dbShips.getShip(ctx.symbol);
+	const response = await api.send({endpoint: `/my/ships/${ctx.symbol}/sell`, method: 'POST', payload: { symbol: ctx.good, units: ctx.units }});
+	if (response.error !== undefined) {
+		throw response;
+	}
+	dbShips.setShipCargo(ctx.symbol, response.data.cargo);
+	// TODO track credits
+	return response;
+}
+
+export async function ship(ctx) {
+	const response = await api.send({endpoint: `/my/ships/${ctx.symbol}`});
+	if (response.error !== undefined) {
+		throw response;
+	}
+	dbShips.setShip(response.data);
+	return response;
+}
+
+export async function survey(ctx) {
+	if (!hasMount(ctx.symbol, 'MOUNT_SURVEYOR_I')) { // we check if a surveyor is mounted on the ship
+		return null;
+	}
+	const ship = dbShips.getShip(ctx.symbol);
+	const asteroidFields = await systems.type({symbol: ship.nav.systemSymbol, type: 'ASTEROID_FIELD'});
+	// TODO if there are multiple fields, find the closest one?
+	await navigate({symbol: ctx.symbol, waypoint: asteroidFields[0].symbol});
+	await orbit(ctx);
+	const response = await api.send({endpoint: `/my/ships/${ctx.symbol}/survey`, method: 'POST'});
+	api.debugLog(response);
+	if (response.error !== undefined) {
+		switch(response.error.code) {
+		case 4000: // ship is on cooldown
+			await api.sleep(response.error.data.cooldown.remainingSeconds  * 1000);
+			return await survey(ctx);
+		default: // yet unhandled error
+			throw response;
+		}
+	}
+	dbSurveys.set(response.data.surveys[0]);
+	await api.sleep(response.data.cooldown.remainingSeconds*1000);
+	return response;
+}
diff --git a/nodejs/lib/systems.js b/nodejs/lib/systems.js
new file mode 100644
index 0000000..e03da6c
--- /dev/null
+++ b/nodejs/lib/systems.js
@@ -0,0 +1,68 @@
+import * as api from './api.js';
+import * as db from '../database/systems.js';
+
+// Retrieves a shipyard's information for ctx.symbol
+export async function shipyard(ctx) {
+	const systemSymbol = ctx.symbol.match(/([^-]+-[^-]+)/)[1]; // TODO generalise this extraction
+	console.log(systemSymbol);
+	return await api.send({endpoint: `/systems/${systemSymbol}/waypoints/${ctx.symbol}/shipyard`});
+}
+
+// Retrieves the system's information for ctx.symbol and caches it in the database
+export async function system(ctx) {
+	let s = db.getSystem(ctx.symbol);
+	if (s === null) {
+		const response = await api.send({endpoint: `/systems/${ctx.symbol}`});
+		if (response.error !== undefined) {
+			switch(response.error.code) {
+			case 404:
+				throw `Error retrieving info for system ${ctx.symbol}: ${response.error.message}`;
+			default: // yet unhandled error
+				throw response;
+			}
+		}
+		s = response.data;
+		db.setSystem(s);
+	}
+	return s;
+}
+
+// Retrieves a list of waypoints that have a specific ctx.trait like a SHIPYARD or a MARKETPLACE in the system ctx.symbol
+export async function trait(ctx) {
+	const w = await waypoints(ctx);
+	return w.filter(s => s.traits.some(t => t.symbol === ctx.trait));
+}
+
+// Retrieves a list of waypoints that have a specific ctx.type like ASTEROID_FIELD in the system ctx.symbol
+export async function type(ctx, response) {
+	const w = await waypoints(ctx);
+	return w.filter(s => s.type === ctx.type);
+}
+
+// Retrieves the system's information for ctx.symbol and caches it in the database
+export async function waypoints(ctx) {
+	await system(ctx);
+	let updated = db.getSystemUpdated(ctx.symbol);
+	// TODO handle uncharted systems
+	if (updated === null) {
+		let waypoints = [];
+		for (let page=1; true; ++page) {
+			const response = await api.send({endpoint: `/systems/${ctx.symbol}/waypoints?limit=20&page=${page}`, priority: 98});
+			if (response.error !== undefined) {
+				switch(response.error.code) {
+				case 404:
+					throw `Error retrieving waypoints for system ${ctx.symbol}: ${response.error.message}`;
+				default: // yet unhandled error
+					throw response;
+				}
+			}
+			waypoints = waypoints.concat(response.data);
+			if (response.meta.total <= response.meta.limit * page) {
+				break;
+			}
+		}
+		db.setSystemWaypoints(ctx.symbol, waypoints);
+		return waypoints;
+	}
+	return db.getSystem(ctx.symbol).waypoints;
+}