Add epic games store free games notification

api-client/epic-games-store.js

@@ -0,0 +1,76 @@
+const productBaseUrl = "https://www.epicgames.com/store/en-US/product/";
+const freeGamesApiUrl =
+    "https://store-site-backend-static.ak.epicgames.com/freeGamesPromotions?locale=en-US&country=US&allowCountries=US";
+
+const isCurrentlyFree = (game) => {
+    const currentDate = Date.now();
+    const giveawayStart =
+        game?.promotions?.promotionalOffers[0]?.promotionalOffers[0]?.startDate;
+    const giveawayEnd =
+        game?.promotions?.promotionalOffers[0]?.promotionalOffers[0]?.endDate;
+
+    if (giveawayStart !== null && giveawayEnd !== null) {
+        return (
+            new Date(giveawayStart) - currentDate < 0 &&
+            new Date(giveawayEnd) - currentDate > 0
+        );
+    }
+
+    return false;
+};
+
+const getFormattedEndDate = (game) => {
+    const giveawayEnd =
+        game?.promotions?.promotionalOffers[0]?.promotionalOffers[0]?.endDate;
+
+    if (giveawayEnd !== null) {
+        return new Date(giveawayEnd).toLocaleString("en-US", {
+            timeZone: "America/Los_Angeles",
+            dateStyle: "full",
+            timeStyle: "long",
+        });
+    }
+
+    return null;
+};
+
+export async function fetchFreeGames() {
+    const response = await fetch(freeGamesApiUrl);
+
+    if (!response.ok) {
+        throw new Error(
+            `Could not obtain Token Price, server responded with: ${response}`
+        );
+    }
+
+    const result = await response.json();
+
+    if (result?.data?.Catalog?.searchStore?.elements) {
+        const elements = result.data.Catalog.searchStore.elements;
+
+        return elements
+            .filter(
+                (game) =>
+                    // Check for a discounted price of $0
+                    game?.price?.totalPrice?.discountPrice === 0 &&
+                    // Make sure it has "promotional offers"
+                    game?.promotions?.promotionalOffers?.length > 0 &&
+                    // Make sure it's actually free
+                    isCurrentlyFree(game)
+            )
+            .map((game) => ({
+                title: game.title,
+                description: game.description,
+                id: game.id,
+                url: new URL(`${game?.productSlug}`, productBaseUrl).href,
+                thumbnailUrl:
+                    game?.keyImages?.find(
+                        (img) => img?.type?.toLowerCase() === "thumbnail"
+                    )?.url ?? game?.keyImages[0]?.url,
+                freeUntil: getFormattedEndDate(game),
+                endDate:
+                    game?.promotions?.promotionalOffers[0]?.promotionalOffers[0]
+                        ?.endDate,
+            }));
+    }
+}

config.example.json

@@ -14,5 +14,8 @@
         "host": "https://example.com",
         "listenHost": "127.0.0.1",
         "listenPort": 5000
+    },
+    "channels": {
+        "deals": ""
     }
 }

cron-tasks/fetch-free-epic-games.js

@@ -0,0 +1,73 @@
+import { EmbedBuilder } from "discord.js";
+
+import { fetchNewGames } from "../models/epic-games-store.js";
+import loadConfig from "../utils/config.js";
+
+const {
+    channels: { deals },
+} = await loadConfig();
+
+const postNewDeals = (client, games) => {
+    if (games.length > 0) {
+        try {
+            const channel = client.channels.cache.get(deals);
+
+            const embeds = games.map((game) =>
+                new EmbedBuilder()
+                    .setTitle(game.title)
+                    .setURL(game.url)
+                    .addFields([
+                        {
+                            name: "Free at",
+                            value: "Epic Games Store",
+                        },
+                        {
+                            name: "Description",
+                            value: game.description,
+                        },
+                        {
+                            name: "Free until",
+                            value: game.freeUntil,
+                        },
+                    ])
+                    .setImage(game.thumbnailUrl)
+            );
+
+            channel.send({
+                embeds: embeds,
+            });
+        } catch (err) {
+            console.error(err);
+        }
+    }
+};
+
+// 2 hours in milliseconds
+const intervalLength = 2 * 60 * 60 * 1000;
+
+let intervalId = null;
+
+export function stop() {
+    if (intervalId !== null) {
+        clearInterval(intervalId);
+    }
+}
+
+export async function start(client) {
+    if (!intervalId) {
+        const freeGames = await fetchNewGames();
+        postNewDeals(client, freeGames);
+
+        intervalId = setInterval(async () => {
+            console.log(
+                "Cron Task: Fetching latest free games from Epic Games Store"
+            );
+
+            const freeGames = await fetchNewGames();
+            postNewDeals(client, freeGames);
+        }, intervalLength);
+    }
+}
+
+process.on("SIGINT", stop);
+process.on("SIGTERM", stop);

cron-tasks/update-wow-token-price.js

@@ -9,7 +9,7 @@ export function stop() {
 }
 
 // 15 minutes in milliseconds
-const intervalLength = 15 * 1000 * 60;
+const intervalLength = 15 * 60 * 1000;
 
 export async function start() {
     if (!intervalId) {

index.js

@@ -120,5 +120,5 @@ const cronTasks = fs
 for (const file of cronTasks) {
     const filePath = path.join(cronTasksPath, file);
     const cronTask = await import(filePath);
-    await cronTask?.start?.();
+    await cronTask?.start?.(client);
 }

models/epic-games-store.js

@@ -0,0 +1,41 @@
+import Store from "../utils/json-store.js";
+import { fetchFreeGames } from "../api-client/epic-games-store.js";
+
+const pickGameId = (game) => game.id;
+
+export async function fetchNewGames() {
+    let freeGames = null;
+
+    try {
+        freeGames = await fetchFreeGames();
+    } catch (err) {
+        console.error(
+            "Error fetching free games from the Epic Games Store:",
+            err
+        );
+    }
+
+    if (freeGames === null) {
+        return;
+    }
+
+    const currentDate = Date.now();
+    const store = new Store("../db/epic-games-store-free-games.json");
+    const currentGames = await store.read();
+    const currentGameIds = currentGames.map(pickGameId);
+
+    // Filter out any games that we have already announced
+    const newFreeGames = freeGames.filter(
+        (game) => !currentGameIds.includes(game.id)
+    );
+
+    // Remove expired games
+    const currentGamesWithExpiredRemoved = currentGames.filter(
+        (game) => new Date(game.endDate) - currentDate > 0
+    );
+
+    // Update file with all current games, removing expired games and adding new ones.
+    await store.write([...newFreeGames, ...currentGamesWithExpiredRemoved]);
+
+    return newFreeGames;
+}

utils/json-store.js

@@ -0,0 +1,41 @@
+import fs from "node:fs/promises";
+import path from "node:path";
+import { fileURLToPath } from "node:url";
+
+export default class JSONStore {
+    constructor(filePath) {
+        this._path = path.join(
+            path.dirname(fileURLToPath(import.meta.url)),
+            filePath
+        );
+    }
+
+    async read() {
+        try {
+            const contents = await fs.readFile(this._path, {
+                encoding: "utf8",
+            });
+
+            return JSON.parse(contents);
+        } catch (err) {
+            console.error(
+                `An error occurred while reading "${this._path}"`,
+                err
+            );
+        }
+
+        return [];
+    }
+
+    async write(data) {
+        try {
+            const contents = JSON.stringify(data);
+            return await fs.writeFile(this._path, contents);
+        } catch (err) {
+            console.error(
+                `An error occurred while writing "${this._path}"`,
+                err
+            );
+        }
+    }
+}