Convert backend to ESM

- About 5 years overdue
- Remove eslint, use bomejs instead

backend/lib/validator/index.js

@@ -1,17 +1,17 @@
-const _                 = require('lodash');
-const Ajv               = require('ajv/dist/2020');
-const error             = require('../error');
-const commonDefinitions = require('../../schema/common.json');
+import Ajv from 'ajv/dist/2020.js';
+import _ from "lodash";
+import commonDefinitions from "../../schema/common.json" with { type: "json" };
+import errs from "../error.js";
 
 RegExp.prototype.toJSON = RegExp.prototype.toString;
 
 const ajv = new Ajv({
-	verbose:         true,
-	allErrors:       true,
+	verbose: true,
+	allErrors: true,
 	allowUnionTypes: true,
-	coerceTypes:     true,
-	strict:          false,
-	schemas:         [commonDefinitions]
+	coerceTypes: true,
+	strict: false,
+	schemas: [commonDefinitions],
 });
 
 /**
@@ -20,26 +20,26 @@ const ajv = new Ajv({
  * @param   {Object} payload
  * @returns {Promise}
  */
-function validator (schema, payload) {
-	return new Promise(function (resolve, reject) {
+const validator = (schema, payload) => {
+	return new Promise((resolve, reject) => {
 		if (!payload) {
-			reject(new error.InternalValidationError('Payload is falsy'));
+			reject(new errs.InternalValidationError("Payload is falsy"));
 		} else {
 			try {
-				let validate = ajv.compile(schema);
-				let valid    = validate(payload);
+				const validate = ajv.compile(schema);
+				const valid = validate(payload);
 
 				if (valid && !validate.errors) {
 					resolve(_.cloneDeep(payload));
 				} else {
-					let message = ajv.errorsText(validate.errors);
-					reject(new error.InternalValidationError(message));
+					const message = ajv.errorsText(validate.errors);
+					reject(new errs.InternalValidationError(message));
 				}
 			} catch (err) {
 				reject(err);
 			}
 		}
 	});
-}
+};
 
-module.exports = validator;
+export default validator;