From ffe3db8c083a5a9a1f2ef4ce4308b17b254020b8 Mon Sep 17 00:00:00 2001
From: Julian Reinhardt <julian.reinhardt@stud.h-da.de>
Date: Tue, 2 Nov 2021 12:22:39 +0100
Subject: [PATCH] Falls back to SQLite if no environment variables are provided

---
 backend/index.js | 133 ++++++++++++++++++++++++-----------------------
 1 file changed, 67 insertions(+), 66 deletions(-)

diff --git a/backend/index.js b/backend/index.js
index f4f7951..8d42d09 100644
--- a/backend/index.js
+++ b/backend/index.js
@@ -44,84 +44,85 @@ async function appStart () {
 
 async function createDbConfigFromEnvironment() {
 	return new Promise((resolve, reject) => {
-		const envMysqlHost  = process.env.DB_MYSQL_HOST || null;
-		const envMysqlPort  = process.env.DB_MYSQL_PORT || null;
-		const envMysqlUser  = process.env.DB_MYSQL_USER || null;
-		const envMysqlName  = process.env.DB_MYSQL_NAME || null;
-		const envSqliteFile = process.env.DB_SQLITE_FILE || null;
+		const envMysqlHost = process.env.DB_MYSQL_HOST || null;
+		const envMysqlPort = process.env.DB_MYSQL_PORT || null;
+		const envMysqlUser = process.env.DB_MYSQL_USER || null;
+		const envMysqlName = process.env.DB_MYSQL_NAME || null;
+		let envSqliteFile  = process.env.DB_SQLITE_FILE || null;
 
-		if ((envMysqlHost && envMysqlPort && envMysqlUser && envMysqlName) || envSqliteFile) {
-			const fs       = require('fs');
-			const filename = (process.env.NODE_CONFIG_DIR || './config') + '/' + (process.env.NODE_ENV || 'default') + '.json';
-			let configData = {};
+		const fs       = require('fs');
+		const filename = (process.env.NODE_CONFIG_DIR || './config') + '/' + (process.env.NODE_ENV || 'default') + '.json';
+		let configData = {};
 
-			try {
-				configData = require(filename);
-			} catch (err) {
-				// do nothing
-			}
+		try {
+			configData = require(filename);
+		} catch (err) {
+			// do nothing
+		}
 
-			if (configData.database && configData.database.engine && !configData.database.fromEnv) {
-				logger.info('Manual db configuration already exists, skipping config creation from environment variables');
+		if (configData.database && configData.database.engine && !configData.database.fromEnv) {
+			logger.info('Manual db configuration already exists, skipping config creation from environment variables');
+			resolve();
+			return;
+		}
+
+		if ((!envMysqlHost || !envMysqlPort || !envMysqlUser || !envMysqlName) && !envSqliteFile){
+			envSqliteFile = '/data/database.sqlite';
+			logger.info(`No valid environment variables for database provided, using default SQLite file '${envSqliteFile}'`);
+		}
+
+		if (envMysqlHost && envMysqlPort && envMysqlUser && envMysqlName) {
+			const newConfig = {
+				fromEnv:  true,
+				engine:   'mysql',
+				host:     envMysqlHost,
+				port:     envMysqlPort,
+				user:     envMysqlUser,
+				password: process.env.DB_MYSQL_PASSWORD,
+				name:     envMysqlName,
+			};
+
+			if (JSON.stringify(configData.database) === JSON.stringify(newConfig)) {
+				// Config is unchanged, skip overwrite
 				resolve();
 				return;
 			}
 
-			if (envMysqlHost && envMysqlPort && envMysqlUser && envMysqlName) {
-				const newConfig = {
-					fromEnv:  true,
-					engine:   'mysql',
-					host:     envMysqlHost,
-					port:     envMysqlPort,
-					user:     envMysqlUser,
-					password: process.env.DB_MYSQL_PASSWORD,
-					name:     envMysqlName,
-				};
+			logger.info('Generating MySQL knex configuration from environment variables');
+			configData.database = newConfig;
 
-				if (JSON.stringify(configData.database) === JSON.stringify(newConfig)) {
-					// Config is unchanged, skip overwrite
-					resolve();
-					return;
+		} else {
+			const newConfig = {
+				fromEnv: true,
+				engine:  'knex-native',
+				knex:    {
+					client:     'sqlite3',
+					connection: {
+						filename: envSqliteFile
+					},
+					useNullAsDefault: true
 				}
-
-				logger.info('Generating MySQL db configuration from environment variables');
-				configData.database = newConfig;
-
-			} else {
-				const newConfig = {
-					fromEnv: true,
-					engine:  'knex-native',
-					knex:    {
-						client:     'sqlite3',
-						connection: {
-							filename: envSqliteFile
-						},
-						useNullAsDefault: true
-					}
-				};
-				if (JSON.stringify(configData.database) === JSON.stringify(newConfig)) {
-					// Config is unchanged, skip overwrite
-					resolve();
-					return;
-				}
-
-				logger.info('Generating Sqlite db configuration from environment variables');
-				configData.database = newConfig;
+			};
+			if (JSON.stringify(configData.database) === JSON.stringify(newConfig)) {
+				// Config is unchanged, skip overwrite
+				resolve();
+				return;
 			}
 
-			// Write config
-			fs.writeFile(filename, JSON.stringify(configData, null, 2), (err) => {
-				if (err) {
-					logger.error('Could not write db config to config file: ' + filename);
-					reject(err);
-				} else {
-					logger.info('Wrote db configuration to config file: ' + filename);
-					resolve();
-				}
-			});
-		} else {
-			resolve();
+			logger.info('Generating SQLite knex configuration');
+			configData.database = newConfig;
 		}
+
+		// Write config
+		fs.writeFile(filename, JSON.stringify(configData, null, 2), (err) => {
+			if (err) {
+				logger.error('Could not write db config to config file: ' + filename);
+				reject(err);
+			} else {
+				logger.debug('Wrote db configuration to config file: ' + filename);
+				resolve();
+			}
+		});
 	});
 }