Convert backend code to ES modules

Bundling code now with Rollup for its flat bundling and tree shaking
support. Front end code still goes through Webpack for browser support.

lib/config.js

@@ -18,8 +18,8 @@
  */
 "use strict";
 
-const path = require("path");
-const fs = require("fs");
+import { resolve } from "path";
+import { readFileSync } from "fs";
 
 const options = {
   CONFIG_DIR: { type: "path", default: "config" },
@@ -133,7 +133,7 @@ function setConfig(name, value, commandLineArgument) {
         return String(val);
       case "path":
         if (!val) return "";
-        return path.resolve(val);
+        return resolve(val);
       default:
         return null;
     }
@@ -182,7 +182,7 @@ setConfig("CONFIG_DIR", options["CONFIG_DIR"]["default"]);
 
 // Configuration file
 const configFile = JSON.parse(
-  fs.readFileSync(path.resolve(allConfig.CONFIG_DIR, "config.json"))
+  readFileSync(resolve(allConfig.CONFIG_DIR, "config.json"))
 );
 for (const [k, v] of Object.entries(configFile)) {
   if (!setConfig(k, v))
@@ -194,7 +194,7 @@ for (const [k, v] of Object.entries(configFile)) {
 for (const [k, v] of Object.entries(options))
   if (v["default"] != null) setConfig(k, v["default"]);
 
-function get(optionName, deviceId) {
+export function get(optionName, deviceId) {
   if (!deviceId) return allConfig[optionName];
 
   optionName = `${optionName}-${deviceId}`;
@@ -222,28 +222,20 @@ function get(optionName, deviceId) {
   return null;
 }
 
-function getDefault(optionName) {
+export function getDefault(optionName) {
   const option = options[optionName];
   if (!option) return null;
 
   let val = option["default"];
-  if (val && option.type === "path") val = path.resolve(val);
+  if (val && option.type === "path") val = resolve(val);
 
   return val;
 }
 
+export let auth;
 // Load authentication scripts
 try {
-  const authScript = fs.readFileSync(
-    path.resolve(allConfig.CONFIG_DIR, "auth.js")
-  );
-  exports.auth = (function(exports) {
-    eval(authScript.toString());
-    return exports;
-  })({});
+  auth = require(resolve(allConfig.CONFIG_DIR, "auth.js"));
 } catch (error) {
   // No auth.js exists
 }
-
-exports.get = get;
-exports.getDefault = getDefault;