Implemented dynamic URLs fetching for the Verifier App (eu-digital-green-certificates#50)

Author: oleksandrsarapulovgl

app/src/main/java/dgca/verifier/app/android/data/Config.kt

@@ -29,22 +29,39 @@ import com.google.gson.annotations.SerializedName
  * and private policy url info.
  */
 data class Config(
-        @SerializedName("origin") val origin: String?,
-        @SerializedName("versions") val versions: Map<String, Version>?,
+    @SerializedName("origin") val origin: String?,
+    @SerializedName("versions") val versions: Map<String, Version>?,
 ) {
-    fun mergeOrOverrideWith(config: Config): Config {
-        return this
+    private companion object {
+        const val DEFAULT_VERSION_NAME = "default"
+        const val STATUS_ENDPOINT_NAME = "status"
+        const val UPDATE_ENDPOINT_NAME = "update"
     }
+
+    private fun getCurrentVersionOrUseDefault(versionName: String): Version? =
+        versions?.get(versionName) ?: versions?.get(DEFAULT_VERSION_NAME)
+
+
+    fun getContextUrl(versionName: String): String =
+        getCurrentVersionOrUseDefault(versionName)?.contextEndpoint?.url ?: ""
+
+    fun getStatusUrl(versionName: String): String =
+        getCurrentVersionOrUseDefault(versionName)?.endpoints?.get(STATUS_ENDPOINT_NAME)?.url ?: ""
+
+
+    fun getUpdateUrl(versionName: String): String =
+        getCurrentVersionOrUseDefault(versionName)?.endpoints?.get(UPDATE_ENDPOINT_NAME)?.url ?: ""
+
 }
 
 data class Endpoint(
-        @SerializedName("url") val url: String?,
-        @SerializedName("pubKeys") val pubKeys: Collection<String>?
+    @SerializedName("url") val url: String?,
+    @SerializedName("pubKeys") val pubKeys: Collection<String>?
 )
 
 data class Version(
-        @SerializedName("privacyUrl") val privacyUrl: String?,
-        @SerializedName("context") val contextEndpoint: Endpoint?,
-        @SerializedName("outdated") val outdated: Boolean?,
-        @SerializedName("endpoints") val endpoints: Map<String, Endpoint>?
+    @SerializedName("privacyUrl") val privacyUrl: String?,
+    @SerializedName("context") val contextEndpoint: Endpoint?,
+    @SerializedName("outdated") val outdated: Boolean?,
+    @SerializedName("endpoints") val endpoints: Map<String, Endpoint>?
 )

app/src/main/java/dgca/verifier/app/android/data/ConfigRepositoryImpl.kt

@@ -22,18 +22,24 @@
 
 package dgca.verifier.app.android.data
 
+import dgca.verifier.app.android.BuildConfig
 import dgca.verifier.app.android.data.local.MutableConfigDataSource
+import dgca.verifier.app.android.data.remote.RemoteConfigDataSource
 import javax.inject.Inject
 
 class ConfigRepositoryImpl @Inject constructor(
-        private val localConfigDataSource: MutableConfigDataSource,
-        private val remoteConfigDataSource: ConfigDataSource
+    private val localConfigDataSource: MutableConfigDataSource,
+    private val remoteConfigDataSource: RemoteConfigDataSource
 ) : ConfigRepository {
     override fun local(): ConfigDataSource {
         return localConfigDataSource
     }
 
-    override fun getConfig(): Config = remoteConfigDataSource.getConfig().apply {
-        localConfigDataSource.setConfig(this)
+    override fun getConfig(): Config {
+        return remoteConfigDataSource.getConfig(
+            localConfigDataSource.getConfig().getContextUrl(BuildConfig.VERSION_NAME)
+        ).apply {
+            localConfigDataSource.setConfig(this)
+        }
     }
 }

app/src/main/java/dgca/verifier/app/android/data/VerifierRepository.kt

@@ -26,7 +26,7 @@ import java.security.cert.Certificate
 
 interface VerifierRepository {
 
-    suspend fun fetchCertificates(): Boolean?
+    suspend fun fetchCertificates(statusUrl: String, updateUrl: String): Boolean?
 
     suspend fun getCertificatesBy(kid: String): List<Certificate>
 }

app/src/main/java/dgca/verifier/app/android/data/VerifierRepositoryImpl.kt

@@ -47,16 +47,16 @@ class VerifierRepositoryImpl @Inject constructor(
     private val validCertList = mutableListOf<String>()
     private val mutex = Mutex()
 
-    override suspend fun fetchCertificates(): Boolean? {
+    override suspend fun fetchCertificates(statusUrl: String, updateUrl: String): Boolean? {
         mutex.withLock {
             return execute {
-                val response = apiService.getCertStatus()
+                val response = apiService.getCertStatus(statusUrl)
                 val body = response.body() ?: return@execute false
                 validCertList.clear()
                 validCertList.addAll(body)
 
                 val resumeToken = preferences.resumeToken
-                fetchCertificate(resumeToken)
+                fetchCertificate(updateUrl, resumeToken)
                 db.keyDao().deleteAllExcept(validCertList.toTypedArray())
                 return@execute true
             }
@@ -68,9 +68,9 @@ class VerifierRepositoryImpl @Inject constructor(
             .map { keyStoreCryptor.decrypt(it.key)?.base64ToX509Certificate()!! }
     }
 
-    private suspend fun fetchCertificate(resumeToken: Long) {
+    private suspend fun fetchCertificate(url: String, resumeToken: Long) {
         val tokenFormatted = if (resumeToken == -1L) "" else resumeToken.toString()
-        val response = apiService.getCertUpdate(tokenFormatted)
+        val response = apiService.getCertUpdate(tokenFormatted, url)
 
         if (!response.isSuccessful || response.code() == HttpURLConnection.HTTP_NO_CONTENT) {
             Timber.d("No content")
@@ -91,7 +91,7 @@ class VerifierRepositoryImpl @Inject constructor(
         newResumeToken?.let {
             val newToken = it.toLong()
             preferences.resumeToken = newToken
-            fetchCertificate(newToken)
+            fetchCertificate(url, newToken)
         }
     }
 

app/src/main/java/dgca/verifier/app/android/data/remote/ApiService.kt

@@ -28,17 +28,19 @@ import retrofit2.Call
 import retrofit2.Response
 import retrofit2.http.GET
 import retrofit2.http.Header
+import retrofit2.http.Url
 
 interface ApiService {
 
-    @GET("/context")
-    fun context(): Call<Config>
+    @GET
+    fun context(@Url url: String): Call<Config>
 
-    @GET("/signercertificateUpdate")
+    @GET
     suspend fun getCertUpdate(
-        @Header("x-resume-token") contentRange: String
+        @Header("x-resume-token") contentRange: String,
+        @Url url: String
     ): Response<ResponseBody>
 
-    @GET("/signercertificateStatus")
-    suspend fun getCertStatus(): Response<List<String>>
+    @GET
+    suspend fun getCertStatus(@Url url: String): Response<List<String>>
 }

app/src/main/java/dgca/verifier/app/android/data/remote/DefaultRemoteConfigDataSource.kt

@@ -0,0 +1,33 @@
+/*
+ *  ---license-start
+ *  eu-digital-green-certificates / dgca-verifier-app-android
+ *  ---
+ *  Copyright (C) 2021 T-Systems International GmbH and all other contributors
+ *  ---
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *  ---license-end
+ *
+ *  Created by osarapulov on 5/17/21 8:23 AM
+ */
+
+package dgca.verifier.app.android.data.remote
+
+import dgca.verifier.app.android.data.Config
+import javax.inject.Inject
+
+class DefaultRemoteConfigDataSource @Inject constructor(private val apiService: ApiService) :
+    RemoteConfigDataSource {
+    override fun getConfig(url: String): Config {
+        return apiService.context(url).execute().body()!!
+    }
+}

app/src/main/java/dgca/verifier/app/android/data/remote/RemoteConfigDataSource.kt

@@ -17,15 +17,13 @@
  *  limitations under the License.
  *  ---license-end
  *
- *  Created by osarapulov on 5/17/21 8:23 AM
+ *  Created by osarapulov on 5/21/21 2:00 PM
  */
 
 package dgca.verifier.app.android.data.remote
 
 import dgca.verifier.app.android.data.Config
-import dgca.verifier.app.android.data.ConfigDataSource
-import javax.inject.Inject
 
-class RemoteConfigDataSource @Inject constructor(private val apiService: ApiService) : ConfigDataSource {
-    override fun getConfig(): Config = apiService.context().execute().body()!!
+interface RemoteConfigDataSource {
+    fun getConfig(url: String): Config
 }

app/src/main/java/dgca/verifier/app/android/di/RepositoryModule.kt

@@ -26,9 +26,13 @@ import dagger.Binds
 import dagger.Module
 import dagger.hilt.InstallIn
 import dagger.hilt.components.SingletonComponent
-import dgca.verifier.app.android.data.*
+import dgca.verifier.app.android.data.ConfigRepository
+import dgca.verifier.app.android.data.ConfigRepositoryImpl
+import dgca.verifier.app.android.data.VerifierRepository
+import dgca.verifier.app.android.data.VerifierRepositoryImpl
 import dgca.verifier.app.android.data.local.LocalConfigDataSource
 import dgca.verifier.app.android.data.local.MutableConfigDataSource
+import dgca.verifier.app.android.data.remote.DefaultRemoteConfigDataSource
 import dgca.verifier.app.android.data.remote.RemoteConfigDataSource
 import javax.inject.Singleton
 
@@ -46,7 +50,8 @@ abstract class RepositoryModule {
 
     @Singleton
     @Binds
-    abstract fun bindRemoteConfigDataSource(configDataSource: RemoteConfigDataSource): ConfigDataSource
+    abstract fun bindRemoteConfigDataSource(configDataSourceDefault: DefaultRemoteConfigDataSource): RemoteConfigDataSource
+
 
     @Singleton
     @Binds

app/src/main/java/dgca/verifier/app/android/settings/SettingsViewModel.kt

@@ -27,15 +27,19 @@ import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import dagger.hilt.android.lifecycle.HiltViewModel
+import dgca.verifier.app.android.BuildConfig
+import dgca.verifier.app.android.data.ConfigRepository
 import dgca.verifier.app.android.data.VerifierRepository
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import javax.inject.Inject
 
 @HiltViewModel
-class SettingsViewModel @Inject constructor(private val verifierRepository: VerifierRepository) :
-    ViewModel() {
+class SettingsViewModel @Inject constructor(
+    private val configRepository: ConfigRepository,
+    private val verifierRepository: VerifierRepository
+) : ViewModel() {
 
     private val _inProgress = MutableLiveData<Boolean>()
     val inProgress: LiveData<Boolean> = _inProgress
@@ -44,7 +48,12 @@ class SettingsViewModel @Inject constructor(private val verifierRepository: Veri
         viewModelScope.launch {
             _inProgress.value = true
             withContext(Dispatchers.IO) {
-                verifierRepository.fetchCertificates()
+                val config = configRepository.local().getConfig()
+                val versionName = BuildConfig.VERSION_NAME
+                verifierRepository.fetchCertificates(
+                    config.getStatusUrl(versionName),
+                    config.getUpdateUrl(versionName)
+                )
             }
             _inProgress.value = false
         }

app/src/main/java/dgca/verifier/app/android/worker/LoadKeysWorker.kt

@@ -28,19 +28,27 @@ import androidx.work.CoroutineWorker
 import androidx.work.WorkerParameters
 import dagger.assisted.Assisted
 import dagger.assisted.AssistedInject
+import dgca.verifier.app.android.BuildConfig
+import dgca.verifier.app.android.data.ConfigRepository
 import dgca.verifier.app.android.data.VerifierRepository
 import timber.log.Timber
 
 @HiltWorker
 class LoadKeysWorker @AssistedInject constructor(
     @Assisted context: Context,
     @Assisted workParams: WorkerParameters,
+    private val configRepository: ConfigRepository,
     private val verifierRepository: VerifierRepository
 ) : CoroutineWorker(context, workParams) {
 
     override suspend fun doWork(): Result {
         Timber.d("key fetching start")
-        val res = verifierRepository.fetchCertificates()
+        val config = configRepository.local().getConfig()
+        val versionName = BuildConfig.VERSION_NAME
+        val res = verifierRepository.fetchCertificates(
+            config.getStatusUrl(versionName),
+            config.getUpdateUrl(versionName)
+        )
         Timber.d("key fetching result: ${res == true}")
         return if (res == true) Result.success() else Result.retry()
     }