Create OkHttp authenticator without token invalidation

datasource/src/main/kotlin/gq/kirmanak/mealient/datasource/AuthenticationProvider.kt

@@ -4,5 +4,4 @@ interface AuthenticationProvider {
 
     suspend fun getAuthHeader(): String?
 
-    suspend fun invalidateAuthHeader()
 }

datasource/src/main/kotlin/gq/kirmanak/mealient/datasource/DataSourceModule.kt

@@ -6,9 +6,8 @@ import dagger.Module
 import dagger.Provides
 import dagger.hilt.InstallIn
 import dagger.hilt.components.SingletonComponent
-import dagger.multibindings.IntoSet
-import gq.kirmanak.mealient.datasource.impl.AuthInterceptor
 import gq.kirmanak.mealient.datasource.impl.CacheBuilderImpl
+import gq.kirmanak.mealient.datasource.impl.MealieAuthenticator
 import gq.kirmanak.mealient.datasource.impl.NetworkRequestWrapperImpl
 import gq.kirmanak.mealient.datasource.impl.OkHttpBuilderImpl
 import gq.kirmanak.mealient.datasource.impl.RetrofitBuilder
@@ -20,7 +19,7 @@ import gq.kirmanak.mealient.datasource.v1.MealieDataSourceV1Impl
 import gq.kirmanak.mealient.datasource.v1.MealieServiceV1
 import kotlinx.serialization.ExperimentalSerializationApi
 import kotlinx.serialization.json.Json
-import okhttp3.Interceptor
+import okhttp3.Authenticator
 import okhttp3.MediaType.Companion.toMediaType
 import okhttp3.OkHttpClient
 import retrofit2.Converter
@@ -91,6 +90,5 @@ interface DataSourceModule {
 
     @Binds
     @Singleton
-    @IntoSet
-    fun bindAuthInterceptor(authInterceptor: AuthInterceptor): Interceptor
+    fun bindAuthenticator(mealieAuthenticator: MealieAuthenticator): Authenticator
 }

datasource/src/main/kotlin/gq/kirmanak/mealient/datasource/impl/AuthInterceptor.kt

@@ -1,58 +0,0 @@
-package gq.kirmanak.mealient.datasource.impl
-
-import androidx.annotation.VisibleForTesting
-import gq.kirmanak.mealient.datasource.AuthenticationProvider
-import kotlinx.coroutines.runBlocking
-import okhttp3.Interceptor
-import okhttp3.Response
-import retrofit2.HttpException
-import javax.inject.Inject
-import javax.inject.Provider
-import javax.inject.Singleton
-
-@Singleton
-class AuthInterceptor @Inject constructor(
-    private val authenticationProvider: Provider<AuthenticationProvider>,
-) : Interceptor {
-
-    override fun intercept(chain: Interceptor.Chain): Response {
-        val token = getAuthHeader()
-        return if (token == null) {
-            proceedWithAuthHeader(chain)
-        } else {
-            try {
-                proceedWithAuthHeader(chain, token)
-            } catch (e: HttpException) {
-                if (e.code() in setOf(401, 403)) {
-                    invalidateAuthHeader()
-                    proceedWithAuthHeader(chain, getAuthHeader())
-                } else {
-                    throw e
-                }
-            }
-        }
-    }
-
-    private fun proceedWithAuthHeader(chain: Interceptor.Chain, token: String? = null): Response {
-        val requestBuilder = chain.request().newBuilder()
-        val request = if (token == null) {
-            requestBuilder.removeHeader(HEADER_NAME).build()
-        } else {
-            requestBuilder.header(HEADER_NAME, token).build()
-        }
-        return chain.proceed(request)
-    }
-
-    private fun getAuthHeader() = runBlocking {
-        authenticationProvider.get().getAuthHeader()
-    }
-
-    private fun invalidateAuthHeader() = runBlocking {
-        authenticationProvider.get().invalidateAuthHeader()
-    }
-
-    companion object {
-        @VisibleForTesting
-        const val HEADER_NAME = "Authorization"
-    }
-}

datasource/src/main/kotlin/gq/kirmanak/mealient/datasource/impl/MealieAuthenticator.kt

@@ -0,0 +1,40 @@
+package gq.kirmanak.mealient.datasource.impl
+
+import androidx.annotation.VisibleForTesting
+import gq.kirmanak.mealient.datasource.AuthenticationProvider
+import kotlinx.coroutines.runBlocking
+import okhttp3.Authenticator
+import okhttp3.Request
+import okhttp3.Response
+import okhttp3.Route
+import javax.inject.Inject
+import javax.inject.Provider
+import javax.inject.Singleton
+
+@Singleton
+class MealieAuthenticator @Inject constructor(
+    private val authenticationProvider: Provider<AuthenticationProvider>,
+) : Authenticator {
+
+    override fun authenticate(route: Route?, response: Response): Request? {
+        val supportsBearer = response.challenges().any { it.scheme == BEARER_SCHEME }
+        val request = response.request
+        return if (supportsBearer && request.header(HEADER_NAME) == null) {
+            getAuthHeader()?.let { request.copyWithHeader(HEADER_NAME, it) }
+        } else {
+            null // Either Bearer is not supported or we've already tried to authenticate
+        }
+    }
+
+    private fun getAuthHeader() = runBlocking { authenticationProvider.get().getAuthHeader() }
+
+    companion object {
+        @VisibleForTesting
+        const val HEADER_NAME = "Authorization"
+        private const val BEARER_SCHEME = "Bearer"
+    }
+}
+
+private fun Request.copyWithHeader(name: String, value: String): Request {
+    return newBuilder().header(name, value).build()
+}

datasource/src/main/kotlin/gq/kirmanak/mealient/datasource/impl/OkHttpBuilderImpl.kt

@@ -2,6 +2,7 @@ package gq.kirmanak.mealient.datasource.impl
 
 import gq.kirmanak.mealient.datasource.CacheBuilder
 import gq.kirmanak.mealient.datasource.OkHttpBuilder
+import okhttp3.Authenticator
 import okhttp3.Interceptor
 import okhttp3.OkHttpClient
 import javax.inject.Inject
@@ -12,10 +13,12 @@ class OkHttpBuilderImpl @Inject constructor(
     private val cacheBuilder: CacheBuilder,
     // Use @JvmSuppressWildcards because otherwise dagger can't inject it (https://stackoverflow.com/a/43149382)
     private val interceptors: Set<@JvmSuppressWildcards Interceptor>,
+    private val authenticator: Authenticator,
 ) : OkHttpBuilder {
 
     override fun buildOkHttp(): OkHttpClient = OkHttpClient.Builder()
         .apply { interceptors.forEach(::addNetworkInterceptor) }
         .cache(cacheBuilder.buildCache())
+        .authenticator(authenticator)
         .build()
 }