chore: Move statistics related functions to it's own file

fix: Extract database constructor to a separate file to ensure we only create one knex instance/db
feat: Add cron for saving the stats to the database every hour
feat: Get cached stats from database (if a stat is not found in the db, generate it)

3 files changed, 54 insertions, 35 deletions

diff --git a/src/api/structures/Database.js b/src/api/structures/Database.js
new file mode 100644
index 0000000..3b256d3
--- /dev/null
+++ b/src/api/structures/Database.js
@@ -0,0 +1,40 @@
+const nodePath = require('path');
+const db = require('knex')({
+	client: process.env.DB_CLIENT,
+	connection: {
+		host: process.env.DB_HOST,
+		user: process.env.DB_USER,
+		password: process.env.DB_PASSWORD,
+		database: process.env.DB_DATABASE,
+		filename: nodePath.join(__dirname, '../../../database/database.sqlite')
+	},
+	postProcessResponse: result => {
+		/*
+			Fun fact: Depending on the database used by the user and given that I don't want
+			to force a specific database for everyone because of the nature of this project,
+			some things like different data types for booleans need to be considered like in
+			the implementation below where sqlite returns 1 and 0 instead of true and false.
+		*/
+		const booleanFields = ['enabled', 'enableDownload', 'isAdmin', 'nsfw'];
+
+		const processResponse = row => {
+			Object.keys(row).forEach(key => {
+				if (booleanFields.includes(key)) {
+					if (row[key] === 0) row[key] = false;
+					else if (row[key] === 1) row[key] = true;
+				}
+			});
+			return row;
+		};
+
+		if (Array.isArray(result)) return result.map(row => processResponse(row));
+		if (typeof result === 'object') return processResponse(result);
+		return result;
+	},
+	useNullAsDefault: process.env.DB_CLIENT === 'sqlite3',
+	userParams: {
+		lastMutationTime: null
+	}
+});
+
+module.exports = db;
diff --git a/src/api/structures/Route.js b/src/api/structures/Route.js
index bb7ba87..24d45b2 100644
--- a/src/api/structures/Route.js
+++ b/src/api/structures/Route.js
@@ -1,39 +1,5 @@
-const nodePath = require('path');
 const JWT = require('jsonwebtoken');
-const db = require('knex')({
-	client: process.env.DB_CLIENT,
-	connection: {
-		host: process.env.DB_HOST,
-		user: process.env.DB_USER,
-		password: process.env.DB_PASSWORD,
-		database: process.env.DB_DATABASE,
-		filename: nodePath.join(__dirname, '../../../database/database.sqlite')
-	},
-	postProcessResponse: result => {
-		/*
-			Fun fact: Depending on the database used by the user and given that I don't want
-			to force a specific database for everyone because of the nature of this project,
-			some things like different data types for booleans need to be considered like in
-			the implementation below where sqlite returns 1 and 0 instead of true and false.
-		*/
-		const booleanFields = ['enabled', 'enableDownload', 'isAdmin', 'nsfw'];
-
-		const processResponse = row => {
-			Object.keys(row).forEach(key => {
-				if (booleanFields.includes(key)) {
-					if (row[key] === 0) row[key] = false;
-					else if (row[key] === 1) row[key] = true;
-				}
-			});
-			return row;
-		};
-
-		if (Array.isArray(result)) return result.map(row => processResponse(row));
-		if (typeof result === 'object') return processResponse(result);
-		return result;
-	},
-	useNullAsDefault: process.env.DB_CLIENT === 'sqlite3'
-});
+const db = require('./Database');
 const moment = require('moment');
 const log = require('../utils/Log');
 
diff --git a/src/api/structures/Server.js b/src/api/structures/Server.js
index 0dec72a..cb97dd1 100644
--- a/src/api/structures/Server.js
+++ b/src/api/structures/Server.js
@@ -14,8 +14,11 @@ const jetpack = require('fs-jetpack');
 const path = require('path');
 const morgan = require('morgan');
 const rfs = require('rotating-file-stream');
+const CronJob = require('cron').CronJob;
 const log = require('../utils/Log');
 
+const Util = require('../utils/Util');
+
 // eslint-disable-next-line no-unused-vars
 const rateLimiter = new RateLimit({
 	windowMs: parseInt(process.env.RATE_LIMIT_WINDOW, 10),
@@ -55,6 +58,9 @@ class Server {
 		// Serve the uploads
 		this.server.use(express.static(path.join(__dirname, '../../../uploads')));
 		this.routesFolder = path.join(__dirname, '../routes');
+
+		// Save the cron job instances in case we want to stop them later
+		this.jobs = {};
 	}
 
 	registerAllTheRoutes() {
@@ -95,6 +101,11 @@ class Server {
 		});
 	}
 
+	createJobs() {
+		// TODO: move into the database config. (we can just show the crontab line for start, later on we can add dropdowns and stuff)
+		this.jobs.stats = new CronJob('* 0 * * * *', Util.saveStatsToDb, null, true);
+	}
+
 	start() {
 		jetpack.dir('uploads/chunks');
 		jetpack.dir('uploads/thumbs/square');
@@ -105,6 +116,8 @@ class Server {
 			log.success(`Backend ready and listening on port ${this.port}`);
 		});
 		server.setTimeout(600000);
+
+		this.createJobs();
 	}
 }