Merge pull request #1931 from AlexeySachkov/private/asachkov/outline-db-connection

[NFC] Outline database connection into a separate file

server/db.js

@@ -0,0 +1,37 @@
+// The main purpose of this file is to provide an interface for database
+// connection. Even though the code is quite simple and basically a tiny
+// wrapper around mongoose package, it works as single point where
+// database setup/config is performed and the interface provided here can be
+// reused by both the main application and all tests which require database
+// connection.
+
+const Mongoose = require('mongoose');
+
+const getMongoDBURL = (config)=>{
+	return config.get('mongodb_uri') ||
+           config.get('mongolab_uri') ||
+           'mongodb://localhost/homebrewery';
+};
+
+const handleConnectionError = (error)=>{
+	if(error) {
+		console.error('Could not connect to a Mongo database: \n');
+		console.error(error);
+		console.error('\nIf you are running locally, make sure mongodb.exe is running and DB URL is configured properly');
+		process.exit(1); // non-zero exit code to indicate an error
+	}
+};
+
+const disconnect = async ()=>{
+	return await Mongoose.disconnect();
+};
+
+const connect = async (config)=>{
+	return await Mongoose.connect(getMongoDBURL(config),
+		{ retryWrites: false }, handleConnectionError);
+};
+
+module.exports = {
+	connect    : connect,
+	disconnect : disconnect
+};