add profile.randomizeUserAgent flag 📝

docs/readme.md

@@ -60,6 +60,30 @@ const retryingDbProfile = withRetrying(dbProfile, {
 const client = createClient(retryingDbProfile, 'my-awesome-program')
 ```
 
+## User agent randomization
+
+By default, `hafas-client` randomizes the client name that you pass into `createClient`, and sends it as [`User-Agent`](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/User-Agent) in a randomized form:
+
+```js
+const createClient('hafas-client')
+// …
+const client = createClient(someProfile, 'my-awesome-program')
+
+await client.journeys(/* … */)
+// User-Agent: my-awee70429some-pre70429ogram
+await client.journeys(/* … */)
+// User-Agent: my-awesom9bb8e2e-prog9bb8e2ram
+```
+
+You can turn this off by setting `profile.randomizeUserAgent` to `false`:
+
+```js
+const client = createClient({
+	...someProfile,
+	randomizeUserAgent: false,
+}, 'my-awesome-program')
+```
+
 ## Logging requests
 
 You can use `profile.logRequest` and `profile.logResponse` to process the raw [Fetch](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) [`Request`](https://developer.mozilla.org/en-US/docs/Web/API/Request) and [`Response`](https://developer.mozilla.org/en-US/docs/Web/API/Response), respectively.

lib/default-profile.js

@@ -65,6 +65,7 @@ const defaultProfile = {
 	salt: null,
 	addChecksum: false,
 	addMicMac: false,
+	randomizeUserAgent: true,
 	logRequest,
 	logResponse,
 

lib/request.js

@@ -66,7 +66,6 @@ const randomizeUserAgent = (userAgent) => {
 
 const md5 = input => createHash('md5').update(input).digest()
 
-// todo [breaking]: remove userAgent parameter
 const request = (ctx, userAgent, reqData) => {
 	const {profile, opt} = ctx
 
@@ -92,7 +91,9 @@ const request = (ctx, userAgent, reqData) => {
 			'Content-Type': 'application/json',
 			'Accept-Encoding': 'gzip, br, deflate',
 			'Accept': 'application/json',
-			'user-agent': randomizeUserAgent(userAgent),
+			'user-agent': profile.randomizeUserAgent
+				? randomizeUserAgent(userAgent)
+				: userAgent,
 			'connection': 'keep-alive', // prevent excessive re-connecting
 		},
 		redirect: 'follow',

test/e2e/lib/util.js

@@ -43,6 +43,7 @@ if (process.env.VCR_MODE && !process.env.VCR_OFF) {
 	const replayer = require('replayer')
 	replayer.configure({
 		headerWhitelist: [
+			// excludes User-Agent & Connection
 			'Content-Type', 'Accept-Encoding', 'Accept',
 		],
 		includeHeaderValues: true,