2 car garage

src/scanner/scanner.ts

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+import Database from "better-sqlite3";
+import cron from "node-cron";
+import { serverManager } from "..";
+
+import Config from "../../data/config.json";
+import Server, { PingResponse } from "../server/server";
+
+const DATA_DIR = "data";
+
+const PINGS_TABLE = "pings";
+const RECORD_TABLE = "record";
+
+/**
+ * SQL Queries
+ */
+const CREATE_TABLE = `
+  CREATE TABLE IF NOT EXISTS {} (
+    timestamp BIGINT NOT NULL,
+    ip TINYTEXT NOT NULL,
+    player_count MEDIUMINT NOT NULL
+  );
+`;
+const CREATE_PINGS_TABLE = CREATE_TABLE.replace("{}", PINGS_TABLE);
+const CREATE_RECORD_TABLE = CREATE_TABLE.replace("{}", RECORD_TABLE);
+
+const CREATE_PINGS_INDEX = `CREATE INDEX IF NOT EXISTS ip_index ON pings (ip, player_count)`;
+const CREATE_TIMESTAMP_INDEX = `CREATE INDEX IF NOT EXISTS timestamp_index on PINGS (timestamp)`;
+
+const INSERT_PING = `
+  INSERT INTO ${PINGS_TABLE} (timestamp, ip, player_count)
+  VALUES (?, ?, ?)
+`;
+const INSERT_RECORD = `
+  INSERT INTO ${RECORD_TABLE} (timestamp, ip, player_count)
+  VALUES (?, ?, ?)
+`;
+const DELETE_OLD_RECORD = `
+  DELETE FROM ${RECORD_TABLE}
+  WHERE ip = ?
+`;
+
+export default class Scanner {
+  private db: Database.Database;
+
+  constructor() {
+    console.log("Loading scanner database");
+    this.db = new Database(`${DATA_DIR}/db.sqlite`);
+
+    console.log("Ensuring tables exist");
+    this.db.exec(CREATE_PINGS_TABLE); // Ensure the pings table exists
+    this.db.exec(CREATE_RECORD_TABLE); // Ensure the record table exists
+
+    console.log("Ensuring indexes exist");
+    this.db.exec(CREATE_PINGS_INDEX); // Ensure the pings index exists
+    this.db.exec(CREATE_TIMESTAMP_INDEX); // Ensure the timestamp index exists
+
+    console.log("Starting server scan");
+    cron.schedule(Config.scanner.updateCron, () => {
+      this.scanServers();
+    });
+  }
+
+  /**
+   * Start a server scan to ping all servers.
+   */
+  private async scanServers(): Promise<void> {
+    console.log(`Scanning servers ${serverManager.getServers().length}`);
+
+    // ping all servers in parallel
+    await Promise.all(
+      serverManager.getServers().map((server) => this.scanServer(server))
+    );
+
+    console.log("Finished scanning servers");
+  }
+
+  /**
+   * Scans a server and inserts the ping into the database.
+   *
+   * @param server the server to scan
+   * @returns a promise that resolves when the server has been scanned
+   */
+  async scanServer(server: Server): Promise<void> {
+    //console.log(`Scanning server ${server.getIP()} - ${server.getType()}`);
+    let response;
+    let online = false;
+
+    try {
+      response = await server.pingServer(server);
+      if (response == undefined) {
+        return; // Server is offline
+      }
+      online = true;
+    } catch (err) {
+      console.log(`Failed to ping ${server.getIP()}`, err);
+      return;
+    }
+
+    if (!online || !response) {
+      return; // Server is offline
+    }
+
+    const { timestamp, players } = response;
+
+    this.insertPing(timestamp, server.getIP(), players.online);
+    this.updateRecord(server, response);
+  }
+
+  /**
+   * Updates the record for a server.
+   *
+   * @param server the server to update
+   * @param response the response to update with
+   */
+  private updateRecord(server: Server, response: PingResponse): void {
+    const ip = server.getIP();
+
+    // select record from database for this server
+    const statement = this.db.prepare(
+      `SELECT * FROM ${RECORD_TABLE} WHERE ip = ?`
+    );
+    const record = statement.get(ip);
+
+    // delete old record
+    if (record) {
+      this.db.prepare(DELETE_OLD_RECORD).run(ip);
+    }
+
+    this.insertRecord(server, response);
+  }
+
+  /**
+   * Inserts a ping into the database.
+   *
+   * @param timestamp the timestamp of the ping
+   * @param ip the IP address of the server
+   * @param playerCount the number of players online
+   */
+  private insertPing(timestamp: number, ip: string, playerCount: number): void {
+    const statement = this.db.prepare(INSERT_PING);
+    statement.run(timestamp, ip, playerCount); // Insert the ping into the database
+  }
+
+  /**
+   * Inserts a record into the database.
+   *
+   * @param server the server to insert
+   * @param response the response to insert
+   */
+  private insertRecord(server: Server, response: PingResponse): void {
+    const { timestamp, players } = response;
+    const ip = server.getIP();
+    const onlineCount = players.online;
+
+    const statement = this.db.prepare(INSERT_RECORD);
+    statement.run(timestamp, ip, onlineCount); // Insert the record into the database
+  }
+}