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Use Dagger to inject different Retrofit and OkHttp object before and after login

I have my Retrofit and OkHttp instances injected. I am changing the headers of my OkHttp object using an Interceptor. In this Interceptor, I set information such as app name, version etc.
I am now adding a login and want to set an authToken to the headers. However, this only exists AFTER login, obviously. So what I want to do is be able to add a new header after login for authToken. However, I can't get access to my OkHttp object as its buried in my module, and I just get my RestClient object injected in my class, with everything else built.
I was thinking of copying all my provides... code and making duplicates for before an after Login. For example, wrap my RestClient in a class called "PreLoginApi" that doesn't have authToken, and then creating another wrapper class called "PostLoginApi" which has the authToken, but this won't work if Dagger creates the objects on app launch.
#Provides
#Singleton
#Named("HeaderInterceptor")
fun provideHeaderInterceptor(context: Context): Interceptor {
val headerMap = context.getHeaderMap()
return Interceptor { chain ->
val original = chain.request()
val builder = original.newBuilder()
headerMap.keys.forEach {
builder.addHeader(it, headerMap[it] ?: "")
}
val request = builder.build()
chain.proceed(request)
}
}
#Provides
fun providesOkHttpClient(
#Named("HeaderInterceptor") headerInterceptor: Interceptor,
): OkHttpClient {
val builder = OkHttpClient.Builder()
.connectTimeout(60, TimeUnit.SECONDS)
.readTimeout(60, TimeUnit.SECONDS)
.addInterceptor(headerInterceptor)
return builder.build()
}
You can see here where I call my extension function Context.getHeaderMap(). Inside this function, I'm retrieving the authToken from EncryptedSharedPreferences.
So ideally, I'd like to be able to tell Dagger to redo this initialisation once I login, because at this stage the authToken will be set. Is it possible to just re-initialise this one module or will I have to wrap my RestClient in another class, and maybe use Lazy loading to initialise the "PostLoginApi"?
Thanks.
EDIT:
I do similar for Firebase FCM token, where I pass in the headerMap during initialisation, like this:
private fun updateFirebaseToken(headerMap: HashMap<String, String>) {
FirebaseMessaging.getInstance().token.addOnCompleteListener(OnCompleteListener { task ->
if (!task.isSuccessful) {
return#OnCompleteListener
}
// Get new FCM registration token
task.result?.let { token ->
headerMap["FirebaseId"] = token
}
})
}
But I don't think I can do something like this for a SharedPrefs value.

How to regenerate token in Android GraphQL?

What is the better approach to regenerate the JWT token using refresh token in Apollo Graphql in Andriod Kotlin?.
Now we are using an Auth interceptor that extends ApolloInterceptor to attach the JWT token in the request header.
I want to check whether the Toke expires from here and it should call another mutation to generate a new token. Then it should proceed with the previous call with the new token.
Please refer to the code below
class AuthInterceptor(private val jwtToken: String) : ApolloInterceptor {
override fun interceptAsync(
request: ApolloInterceptor.InterceptorRequest,
chain: ApolloInterceptorChain,
dispatcher: Executor,
callBack: ApolloInterceptor.CallBack
) {
val header = request.requestHeaders.toBuilder().addHeader(
HEADER_AUTHORIZATION,
"$HEADER_AUTHORIZATION_BEARER $jwtToken"
).build()
chain.proceedAsync(request.toBuilder().requestHeaders(header).build(), dispatcher, callBack)
}
override fun dispose() {}
companion object {
private const val HEADER_AUTHORIZATION = "Authorization"
private const val HEADER_AUTHORIZATION_BEARER = "Bearer"
}
}

If you are using Apollo Android Client V3 and Using Kotlin Coroutine then use Apollo Runtime Dependency and Try HttpInterceptor instead of ApolloInterceptor. I think this is the better/best approach. For Reference Click Here
In your app-level build.gradle file
plugins {
......
id("com.apollographql.apollo3").version("3.5.0")
.....
}
dependencies {
implementation("com.apollographql.apollo3:apollo-runtime")
}
Now write your interceptor for the Apollo client.
FYI: If you've added the Authorization header using Interceptor or using addHttpHeader in client already then remove it or don't add header here val response = chain.proceed(request.newBuilder().addHeader("Authorization", "Bearer $token").build()), just build the request. Otherwise Authorization header will add multiple times in the request. So, be careful.
class AuthorizationInterceptor #Inject constructor(
val tokenRepo: YourTokenRepo
) : HttpInterceptor {
private val mutex = Mutex()
override suspend fun intercept(request: HttpRequest, chain: HttpInterceptorChain): HttpResponse {
var token = mutex.withLock {
// get current token
}
val response = chain.proceed(request.newBuilder().addHeader("Authorization", "Bearer $token").build())
return if (response.statusCode == 401) {
token = mutex.withLock {
// get new token from your refresh token API
}
chain.proceed(request.newBuilder().addHeader("Authorization", "Bearer $token").build())
} else {
response
}
}
}
Configure your Apollo client like below.
ApolloClient.Builder()
.httpServerUrl(BASE_GRAPHQL_URL)
.webSocketServerUrl(BASE_GRAPHQL_WEBSOCKET_ENDPOINT) // if needed
.addHttpHeader("Accept", "application/json")
.addHttpHeader("Content-Type", "application/json")
.addHttpHeader("User-Agent", userAgent)
.addHttpInterceptor(AuthorizationInterceptor(YourTokenRepo))
.httpExposeErrorBody(true)
.build()

Kotlin : Okhttpclient correct way of creating single instance? OkHttpClient doesn't go through server ip check?

I'm new at android kotlin development and currently trying to solve how to correctly create a single instance of OkHttpClient for app-wide usage. I've currently sort-of* created a single instance of client and using it to communicate with the server, however currently the back-end server is not using token/userid for validation but IP check. I can log in the user no problem, but after going to another activity trying to call api, I'm being blocked access by server because apparently IP is not the same. I've used POSTMAN as well as already created a same functioning iOS app that is working with no issue. So my question is am i creating the single instance of OkHttpClient wrong? Or is OkHttpClient not suitable for this kind of ipcheck system? Should i use other library, and if yes, any suggestion and examples?
Thanks in advance
Currently i tried creating it like this :
class MyApplication: Application(){
companion object{
lateinit var client: OkHttpClient
}
override fun onCreate(){
super.onCreate()
client = OkHttpClient()
}
}
Then i created a helper class for it :
class OkHttpRequest {
private var client : OkHttpClient = MyApplication.client
fun POST(url: String, parameters: HashMap<String, String>, callback: Callback): Call {
val builder = FormBody.Builder()
val it = parameters.entries.iterator()
while (it.hasNext()) {
val pair = it.next() as Map.Entry<*, *>
builder.add(pair.key.toString(), pair.value.toString())
}
val formBody = builder.build()
val request = Request.Builder()
.url(url)
.post(formBody)
.build()
val call = client.newCall(request)
call.enqueue(callback)
return call
}
fun GET(url: String, callback: Callback): Call {
val request = Request.Builder()
.url(url)
.build()
val call = client.newCall(request)
call.enqueue(callback)
return call
}
}
Finally I'm using it like this :
val loginUrl = MyApplication.postLoginUrl
var userIdValue = user_id_textfield.text.toString()
var passwordValue = password_textfield.text.toString()
val map: HashMap<String, String> = hashMapOf("email" to userIdValue, "password" to passwordValue)
var request = OkHttpRequest()
request.POST(loginUrl, map, object : Callback {
val responseData = response.body?.string()
// do something with response Data
}
And on another activity after user log in :
val getPaidTo = MyApplication.getPaidTo
var request = OkHttpRequest()
request.GET(getPaidTo, object: Callback{
//do something with data
}

First, don't use your OkHttpClient directly in every Activity or Fragment, use DI and move all of your business logic into Repository or some source of data.
Here I will share some easy way to make REST request with Retrofit, OkHttpClient and Koin, if you want use the same:
WebServiceModule:
val webServiceModule = module {
//Create HttpLoggingInterceptor
single { createLoggingInterceptor() }
//Create OkHttpClient
single { createOkHttpClient(get()) }
//Create WebServiceApi
single { createWebServiceApi(get()) }
}
/**
* Setup a Retrofit.Builder and create a WebServiceApi instance which will hold all HTTP requests
*
* #okHttpClient Factory for HTTP calls
*/
private fun createWebServiceApi(okHttpClient: OkHttpClient): WebServiceApi {
val retrofit = Retrofit.Builder()
.baseUrl(BuildConfig.REST_SERVICE_BASE_URL)
.client(okHttpClient)
.addCallAdapterFactory(CoroutineCallAdapterFactory())
.build()
return retrofit.create(WebServiceApi::class.java)
}
/**
* Create a OkHttpClient which is used to send HTTP requests and read their responses.
*
* #loggingInterceptor logging interceptor
*/
private fun createOkHttpClient(
loggingInterceptor: HttpLoggingInterceptor
): OkHttpClient {
return OkHttpClient.Builder()
.addInterceptor(loggingInterceptor)
.readTimeout(defaultTimeout, TimeUnit.SECONDS)
.connectTimeout(defaultTimeout, TimeUnit.SECONDS)
.build()
}
And now you can inject your WebServiceApi everywhere, but better inject it in your Repository and then use it from some ViewModel
ViewModelModule:
val viewModelModule = module {
//Create an instance of MyRepository
single { MyRepository(webServiceApi = get()) }
}
Hope this help somehow

Okay, after i check with the back-end developer, i figured out the problem wasn't the ip address(it stays the same) but that the cookie was not saved by okhttp, both POSTMan and xcode automatically save the token returned into cookie so i never noticed that was the problem. So after googling a-bit, the solution can be as easy as this:
class MyApplication : Application(){
override fun onCreate(){
val cookieJar = PersistentCookieJar(SetCookieCache(),SharedPrefsCookiePersistor(this))
client = OkHttpClient.Builder()
.cookieJar(cookieJar)
.build()
}
}
With adding persistentCookieJar to gradle.

How to stop Okhttp Authenticator from being called multiple times?

I have an Authenticator like this
#Singleton
class TokenAutheticator #Inject constructor(private val tokenHolder: Lazy<TokenHolder>,private val tokenInterceptor: TokenInterceptor):Authenticator {
override fun authenticate(route: Route?, response: Response): Request? {
val resp = tokenHolder.get().tokenService.relogin(tokenInterceptor.token).execute()
println("### res "+resp.code())
if (resp.code()==200) {
val body = tokenHolder.get().tokenService.relogin(tokenInterceptor.token).execute()?.body()
val newToken = body?.token
println("########## authenticator ########## ")
val url = route?.address()?.url()?.newBuilder()?.addQueryParameter("token", newToken)?.build()
return response.request().newBuilder().url(url).build()
}else{
return null
}
}
}
When the resp.code != 200 the Authenticator is called multiple times.
I am plugging it in Okhttp like this
#Provides
#Singleton
fun provideOkhttp(tokenInterceptor: TokenInterceptor, tokenAutheticator: TokenAutheticator): OkHttpClient {
val logging = HttpLoggingInterceptor()
logging.setLevel(HttpLoggingInterceptor.Level.BODY)
val client = OkHttpClient.Builder()
.authenticator(tokenAutheticator)
.addInterceptor(logging)
.addInterceptor(tokenInterceptor)
.build()
return client
}
So what I want to do is have the Authenticator try it only once and if it is able to get a new token then use the new token from now on and if it can't get a new token then exit. But the Authenticator is called multiple times and the API responds with Too many attempts. Any help is appreciated. Thanks

Only when you return null, Authenticator will stop getting called (stop retrying authentication).
Since you always return something, when response code is 200, it will get called a few times. Luckily, as far I understand, Authenticator detects your endless loop, and breaks out of it eventually.
Basically, you should use Authenticator to react to 401 (and similar) response code and only add authorization header in that case.

Retrofit2: how to save cookies from response

I need to add some authorization information from cookie in response to next requests.
It works in postman - I make authorization request, then second request, which works fine. But if I delete cookies - second request returns error and I have to do authorization request again.
But in my application this second request always returns the same error. I tried to find needed cookie by using interceptor, but I hadn't found it
val client = OkHttpClient.Builder()
.addInterceptor(OAuthInterceptor())
private class OAuthInterceptor : Interceptor {
override fun intercept(chain: Chain): Response {
val request = chain.request()
com.app.logic.toLog("${chain.proceed(request).header("set-cookie")} ") // it's not that cookie what I looking for
val headers = chain.proceed(request).headers()
headers.names().forEach {
val s = headers.get(it)
com.app.logic.toLog("$it -> $s")
}
return chain + (Session.authConsumer?.let { consumer ->
consumer.sign(request).unwrap() as Request
} ?: request)
}
}
Does anybody know what else could I try?

So, finally I've found solution for working with cookies
val client = OkHttpClient.Builder()
.cookieJar(UvCookieJar())
private class UvCookieJar : CookieJar {
private val cookies = mutableListOf<Cookie>()
override fun saveFromResponse(url: HttpUrl, cookieList: List<Cookie>) {
cookies.clear()
cookies.addAll(cookieList)
}
override fun loadForRequest(url: HttpUrl): List<Cookie> =
cookies
}

You can use this this gist on how to intercept cookies when you receive them and send them back in your request in header.