convert to ESM 💥

.eslintrc.json

@@ -1,12 +1,11 @@
 {
 	"extends": "eslint:recommended",
 	"env": {
-		"commonjs": true,
+		"es2022": true,
-		"es6": true,
 		"node": true
 	},
 	"parserOptions": {
-		"ecmaVersion": 2018
+		"sourceType": "module"
 	},
 	"ignorePatterns": [
 		"node_modules"

api-docs.js

@@ -1,7 +1,5 @@
-'use strict'
+import generateApiDocs from 'hafas-rest-api/tools/generate-docs.js'
-
+import {api} from './api.js'
-const generateApiDocs = require('hafas-rest-api/tools/generate-docs')
-const {api} = require('./api')
 
 const HEAD = `\
 # \`v6.db.transport.rest\` API documentation

api.js

@@ -1,19 +1,25 @@
-'use strict'
+// todo: use import assertions once they're supported by Node.js & ESLint
+// https://github.com/tc39/proposal-import-assertions
+import {createRequire} from 'node:module'
+const require = createRequire(import.meta.url)
+
+import {dirname, join as pathJoin} from 'node:path'
+import {fileURLToPath} from 'node:url'
+import createHafas from 'db-hafas'
+import createApi from 'hafas-rest-api'
+import createHealthCheck from 'hafas-client-health-check'
+import Redis from 'ioredis'
+import withCache from 'cached-hafas-client'
+import redisStore from 'cached-hafas-client/stores/redis.js'
+import serveStatic from 'serve-static'
+import {parseBoolean} from 'hafas-rest-api/lib/parse.js'
+import {loyaltyCardParser} from './lib/loyalty-cards.js'
+import {route as stations} from './routes/stations.js'
+import {route as station} from './routes/station.js'
 
-const createHafas = require('db-hafas')
-const createApi = require('hafas-rest-api')
-const createHealthCheck = require('hafas-client-health-check')
-const Redis = require('ioredis')
-const withCache = require('cached-hafas-client')
-const redisStore = require('cached-hafas-client/stores/redis')
-const {join: pathJoin} = require('path')
-const serveStatic = require('serve-static')
-const {parseBoolean} = require('hafas-rest-api/lib/parse')
 const pkg = require('./package.json')
-const {loyaltyCardParser} = require('./lib/loyalty-cards')
-const stations = require('./routes/stations')
-const station = require('./routes/station')
 
+const __dirname = dirname(fileURLToPath(import.meta.url))
 const docsRoot = pathJoin(__dirname, 'docs')
 
 const berlinHbf = '8011160'
@@ -87,7 +93,7 @@ const api = createApi(hafas, config, (api) => {
 	}))
 })
 
-module.exports = {
+export {
 	hafas,
 	config,
 	api,

index.js

@@ -1,6 +1,4 @@
-'use strict'
+import {api, config} from './api.js'
-
-const {api, config} = require('./api')
 
 api.listen(config.port, (err) => {
 	const {logger} = api.locals

lib/db-stations.js

@@ -1,10 +1,13 @@
-'use strict'
+import {createRequire} from 'node:module'
+const require = createRequire(import.meta.url)
 
-const {statSync} = require('fs')
+import {statSync} from 'node:fs'
-const {full: readRawStations} = require('db-stations')
+import _dbStations from 'db-stations'
+const {full: readRawStations} = _dbStations
 
 // We don't have access to the publish date+time of the npm package,
 // so we use the ctime of db-stations/full.ndjson as an approximation.
+// Also require() doesn't make much sense in ES Modules.
 // todo: this is brittle, find a better way, e.g. a build script
 const timeModified = statSync(require.resolve('db-stations/full.ndjson')).ctime
 
@@ -37,4 +40,6 @@ pStations.catch((err) => {
 	process.exit(1) // todo: is this appropriate?
 })
 
-module.exports = pStations
+export {
+	pStations,
+}

lib/loyalty-cards.js

@@ -1,4 +1,5 @@
-const {data: cards} = require('hafas-client/p/db/loyalty-cards')
+import _loyaltyCards from 'hafas-client/p/db/loyalty-cards.js'
+const {data: cards} = _loyaltyCards
 
 const typesByName = new Map([
 	// https://github.com/public-transport/hafas-client/blob/68ecd7c5e976dd2f51c5c64a81600e7e181a8996/p/db/loyalty-cards.js#L6-L11
@@ -29,8 +30,8 @@ const loyaltyCardParser = {
 	parse: parseLoyaltyCard,
 }
 
-module.exports = {
+export {
-	loyaltyCards: cards,
+	cards as loyaltyCards,
 	parseLoyaltyCard,
 	loyaltyCardParser,
 }

package.json

@@ -3,6 +3,7 @@
 	"name": "db-rest",
 	"description": "A clean REST API wrapping around the Deutsche Bahn API.",
 	"version": "5.0.2",
+	"type": "module",
 	"main": "index.js",
 	"author": "Jannis R <mail@jannisr.de>",
 	"homepage": "https://github.com/derhuerst/db-rest/tree/6",

routes/station.js

@@ -1,6 +1,4 @@
-'use strict'
+import {pStations} from '../lib/db-stations.js'
-
-const pStations = require('../lib/db-stations')
 
 const err404 = (msg) => {
 	const err = new Error(msg)
@@ -58,4 +56,6 @@ Returns a stop/station from [\`db-stations@3\`](https://github.com/derhuerst/db-
 	},
 }
 
-module.exports = stationRoute
+export {
+	stationRoute as route,
+}

routes/stations.js

@@ -1,11 +1,10 @@
-'use strict'
+import computeEtag from 'etag'
-
+import serveBuffer from 'serve-buffer'
-const computeEtag = require('etag')
+import autocomplete from 'db-stations-autocomplete'
-const serveBuffer = require('serve-buffer')
+import _cliNative from 'cli-native'
-const autocomplete = require('db-stations-autocomplete')
+const {to: parse} = _cliNative
-const parse = require('cli-native').to
+import createFilter from 'db-stations/create-filter.js'
-const createFilter = require('db-stations/create-filter')
+import {pStations} from '../lib/db-stations.js'
-let pAllStations = require('../lib/db-stations')
 
 const JSON_MIME = 'application/json'
 const NDJSON_MIME = 'application/x-ndjson'
@@ -24,7 +23,7 @@ const toNdjsonBuf = (data) => {
 	return Buffer.concat(chunks, bytes)
 }
 
-pAllStations = pAllStations.then(({data, timeModified}) => {
+const pAllStations = pStations.then(({data, timeModified}) => {
 	const asJson = Buffer.from(JSON.stringify(data), 'utf8')
 	const asNdjson = toNdjsonBuf(data)
 	return {
@@ -202,4 +201,6 @@ stationsRoute.queryParameters = {
 	},
 }
 
-module.exports = stationsRoute
+export {
+	stationsRoute as route,
+}

test/index.js

@@ -1,10 +1,9 @@
-'use strict'
+import tape from 'tape'
-
+import _ndjson from 'ndjson'
-const tape = require('tape')
+const {parse: ndjsonParser} = _ndjson
-const {parse: ndjsonParser} = require('ndjson')
+import {loyaltyCards} from '../lib/loyalty-cards.js'
-const {loyaltyCards} = require('../lib/loyalty-cards')
+import {fetchWithTestApi} from './util.js'
-const {fetchWithTestApi} = require('./util')
+import {pStations as pAllStations} from '../lib/db-stations.js'
-const pAllStations = require('../lib/db-stations')
 
 const NO_JOURNEYS = {
 	// todo?

test/util.js

@@ -1,12 +1,9 @@
-'use strict'
+import createApi from 'hafas-rest-api'
-
+import getPort from 'get-port'
-const createApi = require('hafas-rest-api')
+import {createServer} from 'node:http'
-const getPort = require('get-port')
+import {promisify} from 'node:util'
-const {createServer} = require('http')
+import axios from 'axios'
-const {promisify} = require('util')
+import {config, hafas as unmockedHafas} from '../api.js'
-const axios = require('axios')
-const pkg = require('../package.json')
-const {config, hafas: unmockedHafas} = require('../api')
 
 // adapted from https://github.com/public-transport/hafas-rest-api/blob/60335eacd8332d7f448da875a7498dd97934e360/test/util.js#L40-L77
 const createTestApi = async (mocks, cfg) => {
@@ -50,7 +47,7 @@ const fetchWithTestApi = async (mocks, cfg, path, opt = {}) => {
 	return res
 }
 
-module.exports = {
+export {
 	createTestApi,
 	fetchWithTestApi,
 }