Return default or most recent cached poster (EXPOSUREAPP-6079) (#2741)

* QrCodePosterTemplateCache implementation

* update tests

* remove QrCodePosterTemplateCache

* rename tests

* Timber.e > Timber.d

Co-authored-by: Lukas Lechner <lukas.lechner@sap.com>
Co-authored-by: harambasicluka <64483219+harambasicluka@users.noreply.github.com>

Corona-Warn-App/src/main/assets/default_qr_code_poster_template_android.sha256

+1e972018100828aa63bc2559713cffa22d8db62f3ce56b3edbe72ad8cb7adb16
\ No newline at end of file

Corona-Warn-App/src/main/java/de/rki/coronawarnapp/eventregistration/events/server/qrcodepostertemplate/DefaultQrCodePosterTemplateSource.kt

+package de.rki.coronawarnapp.eventregistration.events.server.qrcodepostertemplate
+
+import android.content.Context
+import dagger.Reusable
+import de.rki.coronawarnapp.util.di.AppContext
+import javax.inject.Inject
+
+@Reusable
+class DefaultQrCodePosterTemplateSource @Inject constructor(@AppContext private val context: Context) {
+
+    fun getDefaultQrCodePosterTemplate() =
+        context.assets.open("default_qr_code_poster_template_android.bin").readBytes()
+}

Corona-Warn-App/src/main/java/de/rki/coronawarnapp/eventregistration/events/server/qrcodepostertemplate/QrCodePosterTemplateServer.kt

 package de.rki.coronawarnapp.eventregistration.events.server.qrcodepostertemplate
 
+import androidx.annotation.VisibleForTesting
 import com.google.protobuf.InvalidProtocolBufferException
 import de.rki.coronawarnapp.server.protocols.internal.pt.QrCodePosterTemplate
 import de.rki.coronawarnapp.util.ZipHelper.readIntoMap
 import de.rki.coronawarnapp.util.ZipHelper.unzip
 import de.rki.coronawarnapp.util.security.SignatureValidation
-import retrofit2.HttpException
 import timber.log.Timber
 import javax.inject.Inject
 import javax.inject.Singleton
@@ -13,48 +13,54 @@ import javax.inject.Singleton
 @Singleton
 class QrCodePosterTemplateServer @Inject constructor(
     private val api: QrCodePosterTemplateApiV1,
+    private val defaultTemplateSource: DefaultQrCodePosterTemplateSource,
     private val signatureValidation: SignatureValidation
 ) {
     suspend fun downloadQrCodePosterTemplate(): QrCodePosterTemplate.QRCodePosterTemplateAndroid {
 
         Timber.d("Start download of QR-Code poster template.")
+        val binaryTemplate = getTemplateFromApiOrCache()
 
-        val response = api.getQrCodePosterTemplate()
-        Timber.d("Received: %s", response)
-
-        if (!response.isSuccessful) {
-            // TODO return cached or default response
-            throw HttpException(response)
-        }
-        if (response.body() == null) {
-            throw IllegalStateException("Response is successful, but body is empty.")
+        return try {
+            QrCodePosterTemplate.QRCodePosterTemplateAndroid.parseFrom(binaryTemplate)
+        } catch (exception: InvalidProtocolBufferException) {
+            throw QrCodePosterTemplateInvalidResponseException(
+                message = "QR Code poster template could not be parsed",
+                cause = exception
+            )
         }
+    }
 
-        val fileMap = response.body()!!.byteStream().unzip().readIntoMap()
-
-        val exportBinary = fileMap[EXPORT_BINARY_FILE_NAME]
-        val exportSignature = fileMap[EXPORT_SIGNATURE_FILE_NAME]
+    @VisibleForTesting(otherwise = VisibleForTesting.PRIVATE)
+    suspend fun getTemplateFromApiOrCache(): ByteArray {
+        return try {
+            val response = api.getQrCodePosterTemplate()
+            if (response.body() == null) {
+                throw IllegalStateException("Response is successful, but body is empty.")
+            }
 
-        if (exportBinary == null || exportSignature == null) {
-            throw QrCodePosterTemplateInvalidResponseException(message = "Unknown files: ${fileMap.keys}")
-        }
+            val fileMap = response.body()!!.byteStream().unzip().readIntoMap()
 
-        val hasValidSignature = signatureValidation.hasValidSignature(
-            exportBinary,
-            SignatureValidation.parseTEKStyleSignature(exportSignature)
-        )
+            val exportBinary = fileMap[EXPORT_BINARY_FILE_NAME]
+            val exportSignature = fileMap[EXPORT_SIGNATURE_FILE_NAME]
 
-        if (!hasValidSignature) {
-            throw QrCodePosterTemplateInvalidResponseException(message = "Invalid Signature!")
-        }
+            if (exportBinary == null || exportSignature == null) {
+                throw QrCodePosterTemplateInvalidResponseException(message = "Unknown files: ${fileMap.keys}")
+            }
 
-        return try {
-            QrCodePosterTemplate.QRCodePosterTemplateAndroid.parseFrom(exportBinary)
-        } catch (exception: InvalidProtocolBufferException) {
-            throw QrCodePosterTemplateInvalidResponseException(
-                message = "QR Code poster template could not be parsed",
-                cause = exception
+            val hasValidSignature = signatureValidation.hasValidSignature(
+                exportBinary,
+                SignatureValidation.parseTEKStyleSignature(exportSignature)
             )
+
+            if (!hasValidSignature) {
+                throw QrCodePosterTemplateInvalidResponseException(message = "Invalid Signature!")
+            }
+
+            exportBinary
+        } catch (exception: Exception) {
+            Timber.d(exception, "Response is not successful, trying to load template from cache")
+            defaultTemplateSource.getDefaultQrCodePosterTemplate()
         }
     }
 

Corona-Warn-App/src/test/java/de/rki/coronawarnapp/appconfig/sources/fallback/DefaultAppConfigSanityCheck.kt → Corona-Warn-App/src/test/java/de/rki/coronawarnapp/appconfig/sources/fallback/DefaultAppConfigTest.kt

@@ -20,7 +20,7 @@ import testhelpers.EmptyApplication
 
 @Config(sdk = [Build.VERSION_CODES.P], application = EmptyApplication::class)
 @RunWith(RobolectricTestRunner::class)
-class DefaultAppConfigSanityCheck : BaseTest() {
+class DefaultAppConfigTest : BaseTest() {
 
     private val configName = "default_app_config_android.bin"
     private val checkSumName = "default_app_config_android.sha256"

Corona-Warn-App/src/test/java/de/rki/coronawarnapp/eventregistration/events/server/qrcodepostertemplate/DefaultQrCodePosterTemplateTest.kt

+package de.rki.coronawarnapp.eventregistration.events.server.qrcodepostertemplate
+
+import android.content.Context
+import android.os.Build
+import androidx.test.core.app.ApplicationProvider
+import de.rki.coronawarnapp.util.HashExtensions.toSHA256
+import io.kotest.matchers.shouldBe
+import io.mockk.MockKAnnotations
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.robolectric.RobolectricTestRunner
+import org.robolectric.annotation.Config
+import testhelpers.BaseTest
+import testhelpers.EmptyApplication
+
+@Config(sdk = [Build.VERSION_CODES.P], application = EmptyApplication::class)
+@RunWith(RobolectricTestRunner::class)
+class DefaultQrCodePosterTemplateTest : BaseTest() {
+
+    private val templateName = "default_qr_code_poster_template_android.bin"
+    private val checkSumName = "default_qr_code_poster_template_android.sha256"
+
+    @Before
+    fun setup() {
+        MockKAnnotations.init(this)
+    }
+
+    val context: Context
+        get() = ApplicationProvider.getApplicationContext()
+
+    @Test
+    fun `current default matches checksum`() {
+        val template = context.assets.open(templateName).readBytes()
+        val sha256 = context.assets.open(checkSumName).readBytes().toString(Charsets.UTF_8)
+        sha256 shouldBe "1e972018100828aa63bc2559713cffa22d8db62f3ce56b3edbe72ad8cb7adb16"
+        template.toSHA256() shouldBe sha256
+    }
+}

Corona-Warn-App/src/test/java/de/rki/coronawarnapp/eventregistration/events/server/qrcodepostertemplate/QrCodePosterTemplateServerTest.kt

@@ -20,6 +20,7 @@ internal class QrCodePosterTemplateServerTest : BaseTest() {
 
     @MockK lateinit var api: QrCodePosterTemplateApiV1
     @MockK lateinit var signatureValidation: SignatureValidation
+    @MockK lateinit var defaultTemplateSource: DefaultQrCodePosterTemplateSource
 
     /**
      * Info: [QrCodePosterTemplateApiV1Test] is testing if the ETag is set correctly
@@ -30,11 +31,13 @@ internal class QrCodePosterTemplateServerTest : BaseTest() {
         MockKAnnotations.init(this)
 
         every { signatureValidation.hasValidSignature(any(), any()) } returns true
+        every { defaultTemplateSource.getDefaultQrCodePosterTemplate() } returns "CACHE".toByteArray()
     }
 
     private fun createInstance() = QrCodePosterTemplateServer(
         api = api,
-        signatureValidation = signatureValidation
+        signatureValidation = signatureValidation,
+        defaultTemplateSource = defaultTemplateSource
     )
 
     @Test
@@ -62,16 +65,14 @@ internal class QrCodePosterTemplateServerTest : BaseTest() {
     }
 
     @Test
-    fun `should throw exception if signature is invalid`() = runBlockingTest {
+    fun `should fallback to cached or default template if signature is invalid`() = runBlockingTest {
         every { signatureValidation.hasValidSignature(any(), any()) } returns false
 
         coEvery {
             api.getQrCodePosterTemplate()
         } returns Response.success(POSTER_BUNDLE.toResponseBody())
 
-        shouldThrow<QrCodePosterTemplateInvalidResponseException> {
-            createInstance().downloadQrCodePosterTemplate()
-        }
+        createInstance().getTemplateFromApiOrCache() shouldBe "CACHE".toByteArray()
     }
 
     @Test
@@ -86,13 +87,12 @@ internal class QrCodePosterTemplateServerTest : BaseTest() {
     }
 
     @Test
-    fun `should return default poster template when response is not successful`() = runBlockingTest {
-        // TODO
-    }
+    fun `should fallback to cached or default template when response is not successful`() = runBlockingTest {
+        coEvery {
+            api.getQrCodePosterTemplate()
+        } returns Response.error(404, "ERROR".toResponseBody())
 
-    @Test
-    fun `should return latest cached template when response is not successful`() = runBlockingTest {
-        // TODO
+        createInstance().getTemplateFromApiOrCache() shouldBe "CACHE".toByteArray()
     }
 
     companion object {