PixelStreamingInfrastructure/Matchmaker/modules/config.js

49 lines
1.8 KiB
JavaScript

// Copyright Epic Games, Inc. All Rights Reserved.
//-- Provides configuration information from file and combines it with default values and command line arguments --//
//-- Hierachy of values: Default Values < Config File < Command Line arguments --//
const fs = require('fs');
const path = require('path');
const argv = require('yargs').argv;
function initConfig(configFile, defaultConfig){
defaultConfig = defaultConfig || {};
// Using object spread syntax: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Spread_syntax#Spread_in_object_literals
let config = {...defaultConfig};
try{
let configData = fs.readFileSync(configFile, 'UTF8');
fileConfig = JSON.parse(configData);
config = {...config, ...fileConfig}
// Update config file with any additional defaults (does not override existing values if default has changed)
fs.writeFileSync(configFile, JSON.stringify(config, null, '\t'), 'UTF8');
} catch(err) {
if (err.code === 'ENOENT') {
console.log("No config file found, writing defaults to log file " + configFile);
fs.writeFileSync(configFile, JSON.stringify(config, null, '\t'), 'UTF8');
} else if (err instanceof SyntaxError) {
console.log(`ERROR: Invalid JSON in ${configFile}, ignoring file config, ${err}`)
} else {
console.log(`ERROR: ${err}`);
}
}
try{
//Make a copy of the command line args and remove the unneccessary ones
//The _ value is an array of any elements without a key
let commandLineConfig = {...argv}
delete commandLineConfig._;
delete commandLineConfig.help;
delete commandLineConfig.version;
delete commandLineConfig['$0'];
config = {...config, ...commandLineConfig}
} catch(err) {
console.log(`ERROR: ${err}`);
}
return config;
}
module.exports = {
init: initConfig
}