rework error handling 💥✅📝

2025-11-04 10:06:32 +02:00 · 2022-05-03 23:21:44 +02:00 · 2022-05-03 23:21:44 +02:00 · 9b263bb379
commit 9b263bb379
parent 0275b65c7a
9 changed files with 435 additions and 149 deletions
--- a/docs/readme.md
+++ b/docs/readme.md
@ -135,6 +135,44 @@ const client = createClient({

 The default `profile.logRequest` [`console.error`](https://nodejs.org/docs/latest-v10.x/api/console.html#console_console_error_data_args)s the request body, if you have set `$DEBUG` to `hafas-client`. Likewise, `profile.logResponse` `console.error`s the response body.

+## Error handling
+
+Unexpected errors – e.g. due to bugs in `hafas-client` itself – aside, its methods may reject with the following errors:
+
+- `HafasError` – A generic error to signal that something HAFAS-related went wrong, either in the client, or in the HAFAS endpoint.
+- `HafasAccessDeniedError` – The HAFAS endpoint has rejected your request because you're not allowed to access it (or the specific API call). Subclass of `HafasError`.
+- `HafasInvalidRequestError` – The HAFAS endpoint reports that an invalid request has been sent. Subclass of `HafasError`.
+- `HafasNotFoundError` – The HAFAS endpoint does not know about such stop/trip/etc. Subclass of `HafasError`.
+- `HafasServerError` – An error occured within the HAFAS endpoint, so that it can't fulfill the request; For example, this happens when HAFAS' internal backend is unavailable. Subclass of `HafasError`.
+
+Each error has the following properties:
+
+- `isHafasError` – Always `true`. Allows you to differente HAFAS-related errors from e.g. network errors.
+- `code` – A string representing the error type for all other error classes, e.g. `INVALID_REQUEST` for `HafasInvalidRequestError`. `null` for plain `HafasError`s.
+- `isCausedByServer` – Boolean, telling you if the HAFAS endpoint says that it couldn't process your request because *it* is unavailable/broken.
+- `hafasCode` – A HAFAS-specific error code, if the HAFAS endpoint returned one; e.g. `H890` when no journeys could be found. `null` otherwise.
+- `request` – The [Fetch API `Request`](https://developer.mozilla.org/en-US/docs/Web/API/Request) of the request.
+- `url` – The URL of the request.
+- `response` – The [Fetch API `Response`](https://developer.mozilla.org/en-US/docs/Web/API/Response).
+
+To check **if an error from `hafas-client` is HAFAS-specific, use `error instanceof HafasError`**:
+
+```js
+const {HafasError} = require('hafas-client/lib/errors')
+
+try {
+	await client.journeys(/* … */)
+} catch (err) {
+	if (err instanceof HafasError) {
+		// HAFAS-specific error
+	} else {
+		// different error, e.g. network (ETIMEDOUT, ENETDOWN)
+	}
+}
+```
+
+To determine **if you should automatically retry an error, use `!error.causedByServer`**.
+
 ## Using `hafas-client` from another language

 If you want to use `hafas-client` to access HAFAS APIs but work with non-Node.js environments, you can use [`hafas-client-rpc`](https://github.com/derhuerst/hafas-client-rpc) to create a [JSON-RPC](https://www.jsonrpc.org) interface that you can send commands to.
--- a/index.js
+++ b/index.js
@ -8,6 +8,7 @@ const defaultProfile = require('./lib/default-profile')
 const validateProfile = require('./lib/validate-profile')
 const {INVALID_REQUEST} = require('./lib/errors')
 const sliceLeg = require('./lib/slice-leg')
+const {HafasError} = require('./lib/errors')

 const isNonEmptyString = str => 'string' === typeof str && str.length > 0

@ -248,11 +249,7 @@ const createClient = (profile, userAgent, opt = {}) => {

 		const {res, common} = await profile.request({profile, opt}, userAgent, req)
 		if (!Array.isArray(res.outConL) || !res.outConL[0]) {
-			const err = new Error('invalid response')
-			// technically this is not a HAFAS error
-			// todo: find a different flag with decent DX
-			err.isHafasError = true
-			throw err
+			throw new HafasError('invalid response, expected outConL[0]', null, {})
 		}

 		const ctx = {profile, opt, common, res}
@ -427,14 +424,10 @@ const createClient = (profile, userAgent, opt = {}) => {

 		const {res, common} = await profile.request({profile, opt}, userAgent, req)
 		if (!res || !Array.isArray(res.locL) || !res.locL[0]) {
-			// todo: proper stack trace?
-			// todo: DRY with lib/request.js
-			const err = new Error('response has no stop')
-			// technically this is not a HAFAS error
-			// todo: find a different flag with decent DX
-			err.isHafasError = true
-			err.code = INVALID_REQUEST
-			throw err
+			throw new HafasError('invalid response, expected locL[0]', null, {
+				// This problem occurs on invalid input. 🙄
+				code: INVALID_REQUEST,
+			})
 		}

 		const ctx = {profile, opt, res, common}
@ -622,9 +615,9 @@ const createClient = (profile, userAgent, opt = {}) => {

 		const {res, common} = await profile.request({profile, opt}, userAgent, req)
 		if (!Array.isArray(res.posL)) {
-			const err = new Error('invalid response')
-			err.shouldRetry = true
-			throw err
+			throw new HafasError('invalid response, expected posL[0]', null, {
+				shouldRetry: true,
+			})
 		}

 		const byDuration = []
--- a/lib/check-if-res-is-ok.js
+++ b/lib/check-if-res-is-ok.js
@ -0,0 +1,44 @@
+'use strict'
+
+const {HafasError, byErrorCode} = require('./errors')
+
+const checkIfResponseIsOk = (_) => {
+	const {
+		body,
+		errProps: baseErrProps,
+	} = _
+
+	const errProps = {
+		...baseErrProps,
+	}
+	if (body.id) errProps.hafasResponseId = body.id
+
+	// Because we want more accurate stack traces, we don't construct the error here,
+	// but only return the constructor & error message.
+	const getError = (_) => {
+		// mutating here is ugly but pragmatic
+		if (_.errTxt) errProps.hafasMessage = _.errTxt
+		if (_.errTxtOut) errProps.hafasDescription = _.errTxtOut
+
+		if (_.err in byErrorCode) return byErrorCode[_.err]
+		return {
+			Error: HafasError,
+			message: body.errTxt || 'unknown error',
+			props: {},
+		}
+	}
+
+	if (body.err && body.err !== 'OK') {
+		const {Error: HafasError, message, props} = getError(body)
+		throw new HafasError(message, body.err, {...errProps, ...props})
+	}
+	if (!body.svcResL || !body.svcResL[0]) {
+		throw new HafasError('invalid/unsupported response structure', null, errProps)
+	}
+	if (body.svcResL[0].err !== 'OK') {
+		const {Error: HafasError, message, props} = getError(body.svcResL[0])
+		throw new HafasError(message, body.svcResL[0].err, {...errProps, ...props})
+	}
+}
+
+module.exports = checkIfResponseIsOk
--- a/lib/errors.js
+++ b/lib/errors.js
@ -5,205 +5,268 @@ const INVALID_REQUEST = 'INVALID_REQUEST'
 const NOT_FOUND = 'NOT_FOUND'
 const SERVER_ERROR = 'SERVER_ERROR'

+class HafasError extends Error {
+	constructor (cleanMessage, hafasCode, props) {
+		const msg = hafasCode
+			? hafasCode + ': ' + cleanMessage
+			: cleanMessage
+		super(msg)
+
+		// generic props
+		this.isHafasError = true
+
+		// error-specific props
+		this.code = null
+		// By default, we take the blame, unless we know for sure.
+		this.isCausedByServer = false
+		this.hafasCode = hafasCode
+		Object.assign(this, props)
+
+		return this
+	}
+}
+
+class HafasAccessDeniedError extends HafasError {
+	constructor (cleanMessage, hafasCode, props) {
+		super(cleanMessage, hafasCode, props)
+		this.code = ACCESS_DENIED
+		return this
+	}
+}
+
+class HafasInvalidRequestError extends HafasError {
+	constructor (cleanMessage, hafasCode, props) {
+		super(cleanMessage, hafasCode, props)
+		this.code = INVALID_REQUEST
+		return this
+	}
+}
+
+class HafasNotFoundError extends HafasError {
+	constructor (cleanMessage, hafasCode, props) {
+		super(cleanMessage, hafasCode, props)
+		this.code = NOT_FOUND
+		return this
+	}
+}
+
+class HafasServerError extends HafasError {
+	constructor (cleanMessage, hafasCode, props) {
+		super(cleanMessage, hafasCode, props)
+		this.code = SERVER_ERROR
+		this.isCausedByServer = true
+		return this
+	}
+}
+
 // https://gist.github.com/derhuerst/79d49c0f04c1c192a5d15756e5af575f/edit
 // todo:
 // `code: 'METHOD_NA', message: 'HCI Service: service method disabled'`
 // "err": "PARAMETER", "errTxt": "HCI Service: parameter invalid"
+// "err": "PARAMETER", "errTxt": "HCI Service: parameter invalid","errTxtOut":"Während der Suche ist ein interner Fehler aufgetreten"
 const byErrorCode = Object.assign(Object.create(null), {
 	H_UNKNOWN: {
-		isServer: false,
-		code: SERVER_ERROR,
+		Error: HafasError,
 		message: 'unknown internal error',
-		statusCode: 500,
+		props: {
+			shouldRetry: true,
+		},
 	},
 	AUTH: {
-		isClient: true,
-		code: ACCESS_DENIED,
+		Error: HafasAccessDeniedError,
 		message: 'invalid or missing authentication data',
-		statusCode: 401
+		props: {
+		},
 	},
 	R0001: {
-		isClient: true,
-		code: INVALID_REQUEST,
+		Error: HafasInvalidRequestError,
 		message: 'unknown method',
-		statusCode: 400
+		props: {
+		},
 	},
 	R0002: {
-		isClient: true,
-		code: INVALID_REQUEST,
+		Error: HafasInvalidRequestError,
 		message: 'invalid or missing request parameters',
-		statusCode: 400
+		props: {
+		},
 	},
 	R0007: {
-		isServer: true,
-		code: SERVER_ERROR,
+		Error: HafasServerError,
 		message: 'internal communication error',
-		statusCode: 500
+		props: {
+			shouldRetry: true,
+		},
 	},
 	R5000: {
-		isClient: true,
-		code: ACCESS_DENIED,
+		Error: HafasAccessDeniedError,
 		message: 'access denied',
-		statusCode: 401
+		props: {
+		},
 	},
 	S1: {
-		isServer: true,
-		code: SERVER_ERROR,
+		Error: HafasServerError,
 		message: 'journeys search: a connection to the backend server couldn\'t be established',
-		statusCode: 503
+		props: {
+			shouldRetry: true,
+		},
 	},
 	LOCATION: {
-		isClient: true,
-		code: INVALID_REQUEST,
+		Error: HafasNotFoundError,
 		message: 'location/stop not found',
-		statusCode: 400
+		props: {
+		},
 	},
 	H390: {
-		isClient: true,
-		code: INVALID_REQUEST,
+		Error: HafasInvalidRequestError,
 		message: 'journeys search: departure/arrival station replaced',
-		statusCode: 400
+		props: {
+		},
 	},
 	H410: {
 		// todo: or is it a client error?
-		// todo: statusCode?
-		isServer: true,
-		code: SERVER_ERROR,
-		message: 'journeys search: incomplete response due to timetable change'
+		Error: HafasServerError,
+		message: 'journeys search: incomplete response due to timetable change',
+		props: {
+		},
 	},
 	H455: {
-		isClient: true,
-		code: INVALID_REQUEST,
+		Error: HafasInvalidRequestError,
 		message: 'journeys search: prolonged stop',
-		statusCode: 400
+		props: {
+		},
 	},
 	H460: {
-		isClient: true,
-		code: INVALID_REQUEST,
+		Error: HafasInvalidRequestError,
 		message: 'journeys search: stop(s) passed multiple times',
-		statusCode: 400
+		props: {
+		},
 	},
 	H500: {
-		isClient: true,
-		code: INVALID_REQUEST,
+		Error: HafasInvalidRequestError,
 		message: 'journeys search: too many trains, connection is not complete',
-		statusCode: 400
+		props: {
+		},
 	},
 	H890: {
-		isClient: true,
-		code: NOT_FOUND,
+		Error: HafasNotFoundError,
 		message: 'journeys search unsuccessful',
-		statusCode: 404
+		props: {
+			shouldRetry: true,
+		},
 	},
 	H891: {
-		isClient: true,
-		code: NOT_FOUND,
+		Error: HafasNotFoundError,
 		message: 'journeys search: no route found, try with an intermediate stations',
-		statusCode: 404
+		props: {
+		},
 	},
 	H892: {
-		isClient: true,
-		code: INVALID_REQUEST,
+		Error: HafasInvalidRequestError,
 		message: 'journeys search: query too complex, try less intermediate stations',
-		statusCode: 400
+		props: {
+		},
 	},
 	H895: {
-		isClient: true,
-		code: INVALID_REQUEST,
+		Error: HafasInvalidRequestError,
 		message: 'journeys search: departure & arrival are too near',
-		statusCode: 400
+		props: {
+		},
 	},
 	H899: {
 		// todo: or is it a client error?
-		// todo: statusCode?
-		isServer: true,
-		code: SERVER_ERROR,
-		message: 'journeys search unsuccessful or incomplete due to timetable change'
+		Error: HafasServerError,
+		message: 'journeys search unsuccessful or incomplete due to timetable change',
+		props: {
+		},
 	},
 	H900: {
 		// todo: or is it a client error?
-		// todo: statusCode?
-		isServer: true,
-		code: SERVER_ERROR,
-		message: 'journeys search unsuccessful or incomplete due to timetable change'
+		Error: HafasServerError,
+		message: 'journeys search unsuccessful or incomplete due to timetable change',
+		props: {
+		},
 	},
 	H9220: {
-		isClient: true,
-		code: NOT_FOUND,
+		Error: HafasNotFoundError,
 		message: 'journeys search: no stations found close to the address',
-		statusCode: 400
+		props: {
+		},
 	},
 	H9230: {
-		isServer: true,
-		code: SERVER_ERROR,
+		Error: HafasServerError,
 		message: 'journeys search: an internal error occured',
-		statusCode: 500
+		props: {
+			shouldRetry: true,
+		},
 	},
 	H9240: {
-		isClient: true,
-		code: NOT_FOUND,
+		Error: HafasNotFoundError,
 		message: 'journeys search unsuccessful',
-		statusCode: 404
+		props: {
+			shouldRetry: true,
+		},
 	},
 	H9250: {
-		isServer: true,
-		code: SERVER_ERROR,
+		Error: HafasServerError,
 		message: 'journeys search: leg query interrupted',
-		statusCode: 500
+		props: {
+			shouldRetry: true,
+		},
 	},
 	H9260: {
-		isClient: true,
-		code: INVALID_REQUEST,
+		Error: HafasInvalidRequestError,
 		message: 'journeys search: unknown departure station',
-		statusCode: 400
+		props: {
+		},
 	},
 	H9280: {
-		isClient: true,
-		code: INVALID_REQUEST,
+		Error: HafasInvalidRequestError,
 		message: 'journeys search: unknown intermediate station',
-		statusCode: 400
+		props: {
+		},
 	},
 	H9300: {
-		isClient: true,
-		code: INVALID_REQUEST,
+		Error: HafasInvalidRequestError,
 		message: 'journeys search: unknown arrival station',
-		statusCode: 400
+		props: {
+		},
 	},
 	H9320: {
-		isClient: true,
-		code: INVALID_REQUEST,
+		Error: HafasInvalidRequestError,
 		message: 'journeys search: the input is incorrect or incomplete',
-		statusCode: 400
+		props: {
+		},
 	},
 	H9360: {
-		isClient: true,
-		code: INVALID_REQUEST,
+		Error: HafasInvalidRequestError,
 		message: 'journeys search: invalid date/time',
-		statusCode: 400
+		props: {
+		},
 	},
 	H9380: {
-		isClient: true,
-		code: INVALID_REQUEST,
+		Error: HafasInvalidRequestError,
 		message: 'journeys search: departure/arrival/intermediate station defined more than once',
-		statusCode: 400
+		props: {
+		},
 	},
 	SQ001: {
-		isServer: true,
-		code: SERVER_ERROR,
+		Error: HafasServerError,
 		message: 'no departures/arrivals data available',
-		statusCode: 503
+		props: {
+		},
 	},
 	SQ005: {
-		isClient: true,
-		code: NOT_FOUND,
+		Error: HafasNotFoundError,
 		message: 'no trips found',
-		statusCode: 404
+		props: {
+		},
 	},
 	TI001: {
-		isServer: true,
-		code: SERVER_ERROR,
+		Error: HafasServerError,
 		message: 'no trip info available',
-		statusCode: 503
+		props: {
+			shouldRetry: true,
+		},
 	}
 })

@ -212,5 +275,10 @@ module.exports = {
 	INVALID_REQUEST,
 	NOT_FOUND,
 	SERVER_ERROR,
+	HafasError,
+	HafasAccessDeniedError,
+	HafasInvalidRequestError,
+	HafasNotFoundError,
+	HafasServerError,
 	byErrorCode,
 }
--- a/lib/request.js
+++ b/lib/request.js
@ -10,7 +10,8 @@ const pick = require('lodash/pick')
 const {stringify} = require('qs')
 const {Request, fetch} = require('cross-fetch')
 const {parse: parseContentType} = require('content-type')
-const {byErrorCode} = require('./errors')
+const {HafasError} = require('./errors')
+const checkIfResponseIsOk = require('./check-if-res-is-ok')

 const proxyAddress = process.env.HTTPS_PROXY || process.env.HTTP_PROXY || null
 const localAddresses = process.env.LOCAL_ADDRESS || null
@ -127,15 +128,14 @@ const request = async (ctx, userAgent, reqData) => {

 	const res = await fetch(url, req)

-	// Async stack traces are not supported everywhere yet, so we create our own.
 	const errProps = {
-		isHafasError: true, // todo: rename to `isHafasClientError`
-		statusCode: res.status,
-		request: req.body, // todo [breaking]: change to fetchReq
-		url: url,
+		request: fetchReq,
+		response: res,
+		url,
 	}

 	if (!res.ok) {
+		// todo [breaking]: make this a FetchError or a HafasClientError?
 		const err = new Error(res.statusText)
 		Object.assign(err, errProps)
 		throw err
@ -145,9 +145,7 @@ const request = async (ctx, userAgent, reqData) => {
 	if (cType) {
 		const {type} = parseContentType(cType)
 		if (type !== 'application/json') {
-			const err = new Error('invalid response content-type: ' + cType)
-			err.response = res
-			throw err
+			throw new HafasError('invalid/unsupported response content-type: ' + cType, null, errProps)
 		}
 	}

@ -155,30 +153,10 @@ const request = async (ctx, userAgent, reqData) => {
 	profile.logResponse(ctx, res, body, reqId)

 	const b = JSON.parse(body)
-	if (b.err) errProps.hafasErrorCode = b.err
-	if (b.errTxt) errProps.hafasErrorMessage = b.errTxt
-	if (b.id) errProps.responseId = b.id
-	if (b.err && b.err !== 'OK') {
-		const err = new Error(b.errTxt || b.err)
-		Object.assign(err, errProps)
-		if (b.err in byErrorCode) {
-			Object.assign(err, byErrorCode[b.err])
-		}
-		throw err
-	}
-	if (!b.svcResL || !b.svcResL[0]) {
-		const err = new Error('invalid/unsupported response structure')
-		Object.assign(err, errProps)
-		throw err
-	}
-	if (b.svcResL[0].err !== 'OK') {
-		const err = new Error(b.svcResL[0].errTxt || b.svcResL[0].err)
-		Object.assign(err, errProps)
-		if (b.svcResL[0].err in byErrorCode) {
-			Object.assign(err, byErrorCode[b.svcResL[0].err])
-		}
-		throw err
-	}
+	checkIfResponseIsOk({
+		body: b,
+		errProps,
+	})

 	const svcRes = b.svcResL[0].res
 	return {
--- a/package.json
+++ b/package.json
@ -70,7 +70,7 @@
 	},
 	"scripts": {
 		"lint": "eslint .",
-		"test-unit": "tap test/*.js test/format/*.js test/parse/*.js",
+		"test-unit": "tap test/lib/*.js test/*.js test/format/*.js test/parse/*.js",
 		"test-integration": "VCR_MODE=playback tap test/e2e/*.js",
 		"test-integration:record": "VCR_MODE=record tap -t60 -j16 test/e2e/*.js",
 		"test-e2e": "VCR_OFF=true tap -t60 -j16 test/e2e/*.js",
--- a/test/fixtures/error-h9360.json
+++ b/test/fixtures/error-h9360.json
@ -0,0 +1,28 @@
+{
+	"ver": "1.44",
+	"ext": "BVG.1",
+	"lang": "deu",
+	"id": "3xmggksuiukkx6wx",
+	"err": "OK",
+	"graph": {
+		"id": "standard",
+		"index": 0
+	},
+	"subGraph": {
+		"id": "global",
+		"index": 0
+	},
+	"view": {
+		"id": "standard",
+		"index": 0,
+		"type": "WGS84"
+	},
+	"svcResL": [
+		{
+			"meth": "StationBoard",
+			"err": "H9360",
+			"errTxt": "HAFAS Kernel: Date outside of the timetable period.",
+			"errTxtOut": "Fehler bei der Datumseingabe oder Datum außerhalb der Fahrplanperiode (01.05.2022 - 10.12.2022)"
+		}
+	]
+}
--- a/test/fixtures/error-location.json
+++ b/test/fixtures/error-location.json
@ -0,0 +1,28 @@
+{
+	"ver": "1.44",
+	"ext": "BVG.1",
+	"lang": "deu",
+	"id": "mmmxakseiuk9g6wg",
+	"err": "OK",
+	"graph": {
+		"id": "standard",
+		"index": 0
+	},
+	"subGraph": {
+		"id": "global",
+		"index": 0
+	},
+	"view": {
+		"id": "standard",
+		"index": 0,
+		"type": "WGS84"
+	},
+	"svcResL": [
+		{
+			"meth": "StationBoard",
+			"err": "LOCATION",
+			"errTxt": "HCI Service: location missing or invalid",
+			"errTxtOut": "Während der Suche ist ein interner Fehler aufgetreten"
+		}
+	]
+}
--- a/test/lib/check-if-res-is-ok.js
+++ b/test/lib/check-if-res-is-ok.js
@ -0,0 +1,109 @@
+'use strict'
+
+const tap = require('tap')
+const checkIfResIsOk = require('../../lib/check-if-res-is-ok')
+const {
+	INVALID_REQUEST,
+	NOT_FOUND,
+	HafasError,
+	HafasInvalidRequestError,
+	HafasNotFoundError,
+} = require('../../lib/errors')
+
+const resParameter = require('../fixtures/error-parameter.json')
+const resNoMatch = require('../fixtures/error-no-match.json')
+const resH9360 = require('../fixtures/error-h9360.json')
+const resLocation = require('../fixtures/error-location.json')
+
+const secret = Symbol('secret')
+
+tap.test('checkIfResponseIsOk properly throws HAFAS "H9360" errors', (t) => {
+	try {
+		checkIfResIsOk({
+			body: resH9360,
+			errProps: {secret},
+		})
+	} catch (err) {
+		t.ok(err)
+
+		t.ok(err instanceof HafasError)
+		t.equal(err.isHafasError, true)
+		t.equal(err.message.slice(0, 7), 'H9360: ')
+		t.ok(err.message.length > 7)
+
+		t.ok(err instanceof HafasInvalidRequestError)
+		t.equal(err.isCausedByServer, false)
+		t.equal(err.code, INVALID_REQUEST)
+		t.equal(err.hafasCode, 'H9360')
+
+		t.equal(err.hafasResponseId, resH9360.id)
+		t.equal(err.hafasMessage, 'HAFAS Kernel: Date outside of the timetable period.')
+		t.equal(err.hafasDescription, 'Fehler bei der Datumseingabe oder Datum außerhalb der Fahrplanperiode (01.05.2022 - 10.12.2022)')
+		t.equal(err.secret, secret)
+
+		t.end()
+	}
+})
+
+tap.test('checkIfResponseIsOk properly throws HAFAS "LOCATION" errors', (t) => {
+	try {
+		checkIfResIsOk({
+			body: resLocation,
+			errProps: {secret},
+		})
+	} catch (err) {
+		t.ok(err)
+
+		t.ok(err instanceof HafasError)
+		t.equal(err.isHafasError, true)
+		t.equal(err.message.slice(0, 10), 'LOCATION: ')
+		t.ok(err.message.length > 10)
+
+		t.ok(err instanceof HafasNotFoundError)
+		t.equal(err.isCausedByServer, false)
+		t.equal(err.code, NOT_FOUND)
+		t.equal(err.hafasCode, 'LOCATION')
+
+		t.equal(err.hafasResponseId, resLocation.id)
+		t.equal(err.hafasMessage, 'HCI Service: location missing or invalid')
+		t.equal(err.hafasDescription, 'Während der Suche ist ein interner Fehler aufgetreten')
+		t.equal(err.secret, secret)
+
+		t.end()
+	}
+})
+
+tap.test('checkIfResponseIsOk properly parses an unknown HAFAS errors', (t) => {
+	const body = {
+		ver: '1.42',
+		id: '1234567890',
+		err: 'FOO',
+		errTxt: 'random errTxt',
+		errTxtOut: 'even more random errTxtOut',
+		svcResL: [],
+	}
+
+	try {
+		checkIfResIsOk({
+			body,
+			errProps: {secret},
+		})
+	} catch (err) {
+		t.ok(err)
+
+		t.ok(err instanceof HafasError)
+		t.equal(err.isHafasError, true)
+		t.equal(err.message, `${body.err}: ${body.errTxt}`)
+
+		t.equal(err.isCausedByServer, false)
+		t.equal(err.code, null)
+		t.equal(err.hafasCode, body.err)
+
+		t.equal(err.hafasResponseId, body.id)
+		t.equal(err.hafasMessage, body.errTxt)
+		t.equal(err.hafasDescription, body.errTxtOut)
+		t.equal(err.secret, secret)
+
+		t.end()
+	}
+})