Merge pull request #1 from KitchenStories/develop

add proper state restoration to HomeConnectAuthorization

README.md

@@ -55,12 +55,15 @@ Example usage with [Lifecycle from architecture components](https://developer.an
 ```
 class HomeConnectAuthorizationFragment : Fragment(R.layout.fragment_home_connect_authorization) {
 
+ private var homeConnectAuthorization: HomeConnectAuthorization? = null
+
  override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
  super.onViewCreated(view, savedInstanceState)
  val webView = view.findViewById<WebView>(R.id.web_view)
  viewLifecycleOwner.lifecycleScope.launch {
  try {
- HomeConnectAuthorization.authorize(webView, onRequestAccessTokenStarted = ::showLoadingIndicator)
+ homeConnectAuthorization = HomeConnectAuthorization()
+ homeConnectAuthorization.authorize(webView, savedInstanceState, onRequestAccessTokenStarted = ::showLoadingIndicator)
  hideLoadingIndicator()
  // user is authorized now
  } catch (e: Exception) {
@@ -69,6 +72,17 @@ class HomeConnectAuthorizationFragment : Fragment(R.layout.fragment_home_connect
  }
  }
 
+ override fun onSaveInstanceState(outState: Bundle) {
+ val webView = requireView().findViewById<WebView>(R.id.web_view)
+ homeConnectAuthorization?.saveInstanceState(webView, outState)
+ super.onSaveInstanceState(outState)
+ }
+
+ override fun onDestroyView() {
+ super.onDestroyView()
+ homeConnectAuthorization = null
+ }
+
 }
 
 ```

app/src/main/java/de/kitchenstories/homeconnect/MainActivity.kt

@@ -1,5 +1,6 @@
 package de.kitchenstories.homeconnect
 
+import android.app.Dialog
 import android.os.Bundle
 import android.util.Log
 import android.view.View
@@ -20,6 +21,8 @@ import com.ajnsnewmedia.kitchenstories.homeconnect.model.programs.StartProgramRe
 import com.ajnsnewmedia.kitchenstories.homeconnect.sdk.HomeConnectAuthorization
 import com.ajnsnewmedia.kitchenstories.homeconnect.sdk.DefaultHomeConnectClient
 import com.ajnsnewmedia.kitchenstories.homeconnect.sdk.HomeConnectClient
+import com.ajnsnewmedia.kitchenstories.homeconnect.util.HomeConnectError
+import com.google.android.material.dialog.MaterialAlertDialogBuilder
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.MainScope
 import kotlinx.coroutines.cancel
@@ -29,19 +32,21 @@ class MainActivity : AppCompatActivity(), CoroutineScope by MainScope() {
 
  private val homeConnectSecretsStore by lazy { MyTestHomeConnectSecretsStore(applicationContext) }
 
- // private val baseUrl = "https://api.home-connect.com/"
- private val baseUrl = "https://simulator.home-connect.com/"
+ private val baseUrl = "https://api.home-connect.com/"
+ //private val baseUrl = "https://simulator.home-connect.com/"
 
  private lateinit var homeConnectAuthenticateWebview: WebView
  private lateinit var ovenControls: ViewGroup
  private lateinit var temperatureInput: EditText
  private val credentials = HomeConnectClientCredentials(
- clientId = BuildConfig.homeConnectClientId,
- clientSecret = BuildConfig.homeConnectClientSecret,
+  clientId = BuildConfig.homeConnectClientId,
+  clientSecret = BuildConfig.homeConnectClientSecret,
  )
 
  private lateinit var homeConnectClient: HomeConnectClient
 
+ private var homeConnectAuthorization: HomeConnectAuthorization? = null
+
  override fun onCreate(savedInstanceState: Bundle?) {
  super.onCreate(savedInstanceState)
  setContentView(R.layout.activity_main)
@@ -52,20 +57,46 @@ class MainActivity : AppCompatActivity(), CoroutineScope by MainScope() {
  if (homeConnectSecretsStore.accessToken != null) {
  showOvenControls()
  } else {
+ val activity = this
  launch {
  try {
- HomeConnectAuthorization.authorize(homeConnectAuthenticateWebview, onRequestAccessTokenStarted = {})
+ homeConnectAuthorization = HomeConnectAuthorization()
+ homeConnectAuthorization?.authorize(homeConnectAuthenticateWebview,
+ savedInstanceState,
+ onRequestAccessTokenStarted = {})
  showOvenControls()
  } catch (e: Throwable) {
+ if (e is HomeConnectError.UserAbortedAuthorization){
+ Toast.makeText(activity,"All is fine, the user aborted ${e.javaClass.canonicalName}:'${e.message}' ", Toast.LENGTH_LONG).show()
+ activity.finish()
+ return@launch
+ }
+ val message = if (e is HomeConnectError && e.message != null) {
+ "The error description ist \"${e.message}\""
+ } else {
+ "something else failed. \"${e.localizedMessage}\""
+ }
+ MaterialAlertDialogBuilder(activity)
+ .setTitle("Something went wrong")
+ .setMessage(message)
+ .setPositiveButton("OK") { _, _ -> }
+ .create()
+ .show()
  Log.e("SampleApp", "authorization failed", e)
  }
  }
  }
  }
 
+ override fun onSaveInstanceState(outState: Bundle) {
+ homeConnectAuthorization?.saveInstanceState(homeConnectAuthenticateWebview, outState)
+ super.onSaveInstanceState(outState)
+ }
+
  override fun onDestroy() {
  super.onDestroy()
  cancel()
+ homeConnectAuthorization = null
  }
 
  private fun showOvenControls() {
@@ -100,17 +131,15 @@ class MainActivity : AppCompatActivity(), CoroutineScope by MainScope() {
 
  launch {
  homeConnectClient.startProgram(
- forApplianceId = oven.id,
- program = StartProgramRequest(
- key = program,
- options = listOf(
- StartProgramOption(
- key = ProgramOptionKey.SetpointTemperature,
- value = enteredTemperature,
- unit = "°C",
- )
+ forApplianceId = oven.id,
+ program = StartProgramRequest(
+ key = program,
+ options = listOf(StartProgramOption(
+ key = ProgramOptionKey.SetpointTemperature,
+ value = enteredTemperature,
+ unit = "°C",
+ )),
  ),
- ),
  )
  }
  }

home-connect/src/main/java/com/ajnsnewmedia/kitchenstories/homeconnect/sdk/DefaultHomeConnectClient.kt

@@ -3,6 +3,7 @@ package com.ajnsnewmedia.kitchenstories.homeconnect.sdk
 import com.ajnsnewmedia.kitchenstories.homeconnect.model.auth.HomeConnectClientCredentials
 import com.ajnsnewmedia.kitchenstories.homeconnect.util.DefaultErrorHandler
 import com.ajnsnewmedia.kitchenstories.homeconnect.util.DefaultHomeConnectApiFactory
+import kotlinx.coroutines.Dispatchers
 
 class DefaultHomeConnectClient(
  baseUrl: String,
@@ -14,6 +15,7 @@ class DefaultHomeConnectClient(
  },
  homeConnectSecretsStore,
  DefaultErrorHandler(),
+ Dispatchers.IO,
 ) {
  init {
  AuthorizationDependencies.baseUrl = baseUrl

home-connect/src/main/java/com/ajnsnewmedia/kitchenstories/homeconnect/sdk/DefaultHomeConnectInteractor.kt

@@ -4,16 +4,27 @@ import android.util.Log
 import com.ajnsnewmedia.kitchenstories.homeconnect.HomeConnectApi
 import com.ajnsnewmedia.kitchenstories.homeconnect.model.appliances.HomeAppliance
 import com.ajnsnewmedia.kitchenstories.homeconnect.model.appliances.HomeApplianceType
+import com.ajnsnewmedia.kitchenstories.homeconnect.model.base.HomeConnectApiError
+import com.ajnsnewmedia.kitchenstories.homeconnect.model.base.HomeConnectApiErrorResponse
 import com.ajnsnewmedia.kitchenstories.homeconnect.model.base.HomeConnectApiRequest
+import com.ajnsnewmedia.kitchenstories.homeconnect.model.jsonadapters.HomeConnectMoshiBuilder
 import com.ajnsnewmedia.kitchenstories.homeconnect.model.programs.AvailableProgram
 import com.ajnsnewmedia.kitchenstories.homeconnect.model.programs.StartProgramRequest
 import com.ajnsnewmedia.kitchenstories.homeconnect.util.ErrorHandler
 import com.ajnsnewmedia.kitchenstories.homeconnect.util.HomeConnectApiFactory
+import com.ajnsnewmedia.kitchenstories.homeconnect.util.HomeConnectError
+import kotlinx.coroutines.CoroutineDispatcher
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
+import okhttp3.ResponseBody
+import okio.Buffer
+import retrofit2.HttpException
 
 internal class DefaultHomeConnectInteractor(
- private val homeConnectApiFactory: HomeConnectApiFactory,
- private val homeConnectSecretsStore: HomeConnectSecretsStore,
- private val errorHandler: ErrorHandler,
+ private val homeConnectApiFactory: HomeConnectApiFactory,
+ private val homeConnectSecretsStore: HomeConnectSecretsStore,
+ private val errorHandler: ErrorHandler,
+ private val ioDispatcher: CoroutineDispatcher,
 ) : HomeConnectClient {
 
  private val homeConnectApi: HomeConnectApi by lazy { homeConnectApiFactory.getHomeConnectApi() }
@@ -50,12 +61,28 @@ internal class DefaultHomeConnectInteractor(
 
  override suspend fun startProgram(forApplianceId: String, program: StartProgramRequest) {
  try {
- homeConnectApi.startProgram(forApplianceId, HomeConnectApiRequest(program))
+ val response = homeConnectApi.startProgram(forApplianceId, HomeConnectApiRequest(program))
+ if (!response.isSuccessful) {
+ val errorDescription = response.errorBody()?.tryParsingApiError()?.description
+ throw HomeConnectError.Unspecified(message = errorDescription ?: "", cause = HttpException(response))
+ }
  } catch (e: Throwable) {
  Log.e("HomeConnectApi", "starting a program failed", e)
  errorHandler.handle(e)
  }
  }
 
+ private suspend fun ResponseBody.tryParsingApiError(): HomeConnectApiError? {
+ val error = try {
+ val errorJsonAdapter = HomeConnectMoshiBuilder.moshiInstance.adapter(HomeConnectApiErrorResponse::class.java)
+ withContext(ioDispatcher) {
+ errorJsonAdapter.fromJson(Buffer().readFrom(this@tryParsingApiError.byteStream()))
+ }
+ } catch (e: Throwable) {
+ null
+ }
+ return error?.error
+ }
+
 }
 

home-connect/src/main/java/com/ajnsnewmedia/kitchenstories/homeconnect/sdk/HomeConnectAuthorization.kt

@@ -2,6 +2,9 @@ package com.ajnsnewmedia.kitchenstories.homeconnect.sdk
 
 import android.annotation.SuppressLint
 import android.net.Uri
+import android.os.Bundle
+import android.os.Parcel
+import android.os.Parcelable
 import android.util.Log
 import android.webkit.WebChromeClient
 import android.webkit.WebResourceRequest
@@ -15,6 +18,7 @@ import com.ajnsnewmedia.kitchenstories.homeconnect.model.jsonadapters.HomeConnec
 import com.ajnsnewmedia.kitchenstories.homeconnect.util.DefaultErrorHandler
 import com.ajnsnewmedia.kitchenstories.homeconnect.util.DefaultTimeProvider
 import com.ajnsnewmedia.kitchenstories.homeconnect.util.HomeConnectApiFactory
+import com.ajnsnewmedia.kitchenstories.homeconnect.util.HomeConnectAuthorizationState
 import com.ajnsnewmedia.kitchenstories.homeconnect.util.HomeConnectError
 import com.squareup.moshi.JsonReader
 import kotlinx.coroutines.suspendCancellableCoroutine
@@ -33,57 +37,81 @@ internal object AuthorizationDependencies {
 
 }
 
+private const val AUTHORIZATION_SAVED_STATE = "AUTHORIZATION_SAVED_STATE"
+
 // TODO move testable code without web view dependency somewhere else and write tests
 // TODO make sure that no memory leaks happen here
-object HomeConnectAuthorization {
+class HomeConnectAuthorization {
+
+ private var authorizationCode: String? = null
 
  /**
- * @param onRequestAccessTokenStarted This callback will be triggered when the user has given his consent and the request for the initial
- * access token is ongoing. Use this to e.g. show a loading indicator to keep the user informed about the progress.
+ * @param onRequestAccessTokenStarted This callback will be triggered when the user went through the web authorization flow, has given
+ * their consent and the request for the initial access token is ongoing. Use this to e.g. show a loading indicator to keep the user
+ * informed about the progress.
  */
- suspend fun authorize(webView: WebView, onRequestAccessTokenStarted: () -> Unit) {
- val authorizationCode = initWebAuthorization(webView)
- loadAccessToken(authorizationCode, onRequestAccessTokenStarted)
+ suspend fun authorize(webView: WebView, savedInstanceState: Bundle?, onRequestAccessTokenStarted: () -> Unit) {
+ val savedState: HomeConnectAuthorizationState? = savedInstanceState?.getParcelable(AUTHORIZATION_SAVED_STATE)
+ if (savedState?.authorizationCode != null) {
+ loadAccessToken(savedState.authorizationCode, onRequestAccessTokenStarted)
+ } else {
+ val authorizationCode = initWebAuthorization(webView, savedState?.webViewState)
+ loadAccessToken(authorizationCode, onRequestAccessTokenStarted)
+ }
+ }
+
+ fun saveInstanceState(webView: WebView, outState: Bundle) {
+ val webViewState = Bundle(1)
+ webView.saveState(webViewState)
+ outState.putParcelable(AUTHORIZATION_SAVED_STATE, HomeConnectAuthorizationState(webViewState, authorizationCode))
  }
 
  @SuppressLint("SetJavaScriptEnabled")
- private suspend fun initWebAuthorization(webView: WebView): String = suspendCancellableCoroutine { continuation ->
- webView.settings.javaScriptEnabled = true
- webView.webViewClient = object : WebViewClient() {
- override fun onPageFinished(view: WebView?, url: String?) {
- super.onPageFinished(view, url)
- if (url != null && url.startsWith("https://apiclient.home-connect.com/o2c.html")) {
- val uri = Uri.parse(url)
- val authorizationCode = uri.parseAuthorizationCode()
- if (authorizationCode != null) {
- continuation.resume(authorizationCode)
- } else {
- val errorDescription = uri.parseErrorDescription()
- continuation.resumeWithException(HomeConnectError.Unspecified(errorDescription, null))
+ private suspend fun initWebAuthorization(webView: WebView, webViewState: Bundle?): String =
+ suspendCancellableCoroutine { continuation ->
+ webView.settings.javaScriptEnabled = true
+ webView.webViewClient = object : WebViewClient() {
+ override fun onPageFinished(view: WebView?, url: String?) {
+ super.onPageFinished(view, url)
+ if (url != null && url.startsWith("https://apiclient.home-connect.com/o2c.html")) {
+ val uri = Uri.parse(url)
+ val authorizationCode = uri.parseAuthorizationCode()
+ this@HomeConnectAuthorization.authorizationCode = authorizationCode
+ if (authorizationCode != null) {
+ continuation.resume(authorizationCode)
+ } else {
+ val errorDescription = uri.parseErrorDescription()
+ val error = uri.parseError()
+ continuation.resumeWithException(HomeConnectError.getExceptionFromError(error, errorDescription, cause = null))
+ }
+ }
  }
- }
- }
 
- override fun onReceivedHttpError(view: WebView?, request: WebResourceRequest?, errorResponse: WebResourceResponse?) {
- super.onReceivedHttpError(view, request, errorResponse)
- if (request != null && request.isForMainFrame) {
- val errorDescription = errorResponse?.data?.parseErrorDescription()
- continuation.resumeWithException(HomeConnectError.Unspecified(errorDescription, null))
+ override fun onReceivedHttpError(view: WebView?, request: WebResourceRequest?, errorResponse: WebResourceResponse?) {
+ super.onReceivedHttpError(view, request, errorResponse)
+ if (request != null && request.isForMainFrame) {
+ val errorDescription = errorResponse?.data?.parseErrorDescription()
+ continuation.resumeWithException(HomeConnectError.Unspecified(errorDescription, null))
+ }
+ }
  }
- }
- }
- webView.webChromeClient = object : WebChromeClient() {}
+ webView.webChromeClient = object : WebChromeClient() {}
 
- val baseUrl = AuthorizationDependencies.baseUrl
- val credentials = AuthorizationDependencies.credentials
- val authUrl = "${baseUrl}security/oauth/authorize?client_id=${credentials.clientId}&response_type=code"
- webView.loadUrl(authUrl)
+ if (webViewState != null) {
+ webView.restoreState(webViewState)
+ } else {
+ val baseUrl = AuthorizationDependencies.baseUrl
+ val credentials = AuthorizationDependencies.credentials
+ val authUrl = "${baseUrl}security/oauth/authorize?client_id=${credentials.clientId}&response_type=code"
+ webView.loadUrl(authUrl)
+ }
 
- continuation.invokeOnCancellation {
- webView.webChromeClient = null
- webView.stopLoading()
- }
- }
+ continuation.invokeOnCancellation {
+ webView.webChromeClient = null
+ webView.stopLoading()
+ webView.destroy()
+ }
+ }
 
  private suspend fun loadAccessToken(authorizationCode: String, onRequestAccessTokenStarted: () -> Unit) {
  onRequestAccessTokenStarted()
@@ -112,6 +140,8 @@ object HomeConnectAuthorization {
  */
  private fun Uri.parseErrorDescription() = this.getQueryParameter("error_description")?.let { URLDecoder.decode(it, "UTF-8") }
 
+ private fun Uri.parseError() = this.getQueryParameter("error")?.let { URLDecoder.decode(it, "UTF-8") }
+
  /**
  * Parses the error description from the json response after an HTTP error is encountered during web authorization flow
  */