with $RANDOM_LOCAL_ADDRESSES_RANGE, use localaddress-agent

This allows sending requests with a large number of IPv6 addresses.

api.js

@@ -7,7 +7,10 @@ import {dirname, join as pathJoin} from 'node:path'
 import {fileURLToPath} from 'node:url'
 import _cliNative from 'cli-native'
 const {to: parse} = _cliNative
-import {createVbbHafas as createHafas} from 'vbb-hafas'
+import {
+	createVbbHafas as createHafas,
+	defaults as vbbHafasDefaults,
+} from 'vbb-hafas'
 import createHealthCheck from 'hafas-client-health-check'
 import Redis from 'ioredis'
 import {createCachedHafasClient as withCache} from 'cached-hafas-client'
@@ -28,12 +31,28 @@ const docsRoot = pathJoin(__dirname, 'docs')
 
 const berlinFriedrichstr = '900100001'
 
+const customVbbProfile = {
+	...vbbHafasDefaults.profile,
+}
+
+// todo: DRY env var check with localaddress-agent/random-from-env.js
+// Currently, this is impossible: localaddress-agent is an optional dependencies, so we rely on it to check the env var.
+if (process.env.RANDOM_LOCAL_ADDRESSES_RANGE) {
+	const {randomLocalAddressAgent} = await import('localaddress-agent/random-from-env.js')
+
+	customVbbProfile.transformReq = (_, req) => {
+		req.agent = randomLocalAddressAgent
+		return req
+	}
+}
+
 let hafas = createHafas(
 	// seems like `vbb-rest` is being redirected
 	// pkg.name,
 	// seems like these are being blocked
 	// require('crypto').randomBytes(10).toString('hex'),
 	'App/4.5.1 (iPhone; iOS 15.2; Scale/3.00)',
+	{profile: customVbbProfile},
 )
 let healthCheck = createHealthCheck(hafas, berlinFriedrichstr)
 

package.json

@@ -44,6 +44,9 @@
 		"vbb-stations": "^8.2.0",
 		"vbb-stations-autocomplete": "^4.4.0"
 	},
+	"optionalDependencies": {
+		"localaddress-agent": "^2.1.1"
+	},
 	"scripts": {
 		"build": "REDIS_URL='' ./build/index.js",
 		"start": "node index.js",