refactor: store API keys in app preferences

app/src/main/java/space/hackenslacker/kanbn4droid/app/BoardsActivity.kt

@@ -24,9 +24,9 @@ import com.google.android.material.textfield.TextInputLayout
 import kotlinx.coroutines.Job
 import kotlinx.coroutines.launch
 import space.hackenslacker.kanbn4droid.app.auth.ApiKeyStore
-import space.hackenslacker.kanbn4droid.app.auth.CredentialManagerApiKeyStore
 import space.hackenslacker.kanbn4droid.app.auth.HttpKanbnApiClient
 import space.hackenslacker.kanbn4droid.app.auth.KanbnApiClient
+import space.hackenslacker.kanbn4droid.app.auth.PreferencesApiKeyStore
 import space.hackenslacker.kanbn4droid.app.auth.SessionPreferences
 import space.hackenslacker.kanbn4droid.app.auth.SessionStore
 import space.hackenslacker.kanbn4droid.app.boards.BoardSummary
@@ -257,7 +257,7 @@ class BoardsActivity : AppCompatActivity() {
 
     protected fun provideApiKeyStore(): ApiKeyStore {
         return MainActivity.dependencies.apiKeyStoreFactory?.invoke(this)
-            ?: CredentialManagerApiKeyStore(this)
+            ?: PreferencesApiKeyStore(this)
     }
 
     protected fun provideApiClient(): KanbnApiClient {

app/src/main/java/space/hackenslacker/kanbn4droid/app/MainActivity.kt

@@ -19,10 +19,11 @@ import kotlinx.coroutines.cancel
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import space.hackenslacker.kanbn4droid.app.auth.ApiKeyStore
+import space.hackenslacker.kanbn4droid.app.auth.AuthFailureReason
 import space.hackenslacker.kanbn4droid.app.auth.AuthResult
-import space.hackenslacker.kanbn4droid.app.auth.CredentialManagerApiKeyStore
 import space.hackenslacker.kanbn4droid.app.auth.HttpKanbnApiClient
 import space.hackenslacker.kanbn4droid.app.auth.KanbnApiClient
+import space.hackenslacker.kanbn4droid.app.auth.PreferencesApiKeyStore
 import space.hackenslacker.kanbn4droid.app.auth.SessionPreferences
 import space.hackenslacker.kanbn4droid.app.auth.SessionStore
 import space.hackenslacker.kanbn4droid.app.auth.UrlNormalizer
@@ -100,15 +101,17 @@ class MainActivity : AppCompatActivity() {
             return false
         }
 
-        return when (apiClient.healthCheck(storedBaseUrl, storedApiKey)) {
+        return when (val authResult = apiClient.healthCheck(storedBaseUrl, storedApiKey)) {
             AuthResult.Success -> {
                 openBoards()
                 true
             }
 
             is AuthResult.Failure -> {
-                withContext(Dispatchers.IO) {
-                    apiKeyStore.invalidateApiKey(storedBaseUrl)
+                if (authResult.reason == AuthFailureReason.Authentication) {
+                    withContext(Dispatchers.IO) {
+                        apiKeyStore.invalidateApiKey(storedBaseUrl)
+                    }
                 }
                 false
             }
@@ -200,7 +203,7 @@ class MainActivity : AppCompatActivity() {
 
     protected fun provideApiKeyStore(): ApiKeyStore {
         return dependencies.apiKeyStoreFactory?.invoke(this)
-            ?: CredentialManagerApiKeyStore(this)
+            ?: PreferencesApiKeyStore(this)
     }
 
     protected fun provideApiClient(): KanbnApiClient {

app/src/main/java/space/hackenslacker/kanbn4droid/app/auth/ApiKeyStore.kt

@@ -1,13 +1,6 @@
 package space.hackenslacker.kanbn4droid.app.auth
 
 import android.content.Context
-import android.content.SharedPreferences
-import androidx.credentials.ClearCredentialStateRequest
-import androidx.credentials.CreatePasswordRequest
-import androidx.credentials.CredentialManager
-import androidx.credentials.GetCredentialRequest
-import androidx.credentials.GetPasswordOption
-import androidx.credentials.PasswordCredential
 
 interface ApiKeyStore {
     suspend fun saveApiKey(baseUrl: String, apiKey: String): Result<Unit>
@@ -15,60 +8,33 @@ interface ApiKeyStore {
     suspend fun invalidateApiKey(baseUrl: String): Result<Unit>
 }
 
-class CredentialManagerApiKeyStore(
-    private val context: Context,
-    private val credentialManager: CredentialManager = CredentialManager.create(context),
+class PreferencesApiKeyStore(
+    context: Context,
 ) : ApiKeyStore {
-    private val invalidatedPreferences: SharedPreferences =
-        context.getSharedPreferences(INVALIDATED_PREFS_NAME, Context.MODE_PRIVATE)
+    private val preferences = context.getSharedPreferences(PREFERENCES_NAME, Context.MODE_PRIVATE)
 
     override suspend fun saveApiKey(baseUrl: String, apiKey: String): Result<Unit> {
         return runCatching {
-            credentialManager.createCredential(
-                context,
-                CreatePasswordRequest(id = CREDENTIAL_ID, password = apiKey),
-            )
-            markInvalidated(baseUrl, false)
+            preferences.edit().putString(API_KEY_PREFERENCE_KEY, apiKey).apply()
             Unit
         }
     }
 
     override suspend fun getApiKey(baseUrl: String): Result<String?> {
         return runCatching {
-            if (isInvalidated(baseUrl)) {
-                return@runCatching null
-            }
-
-            val response = credentialManager.getCredential(
-                context,
-                GetCredentialRequest(listOf(GetPasswordOption())),
-            )
-
-            val credential = response.credential as? PasswordCredential ?: return@runCatching null
-            if (credential.id == CREDENTIAL_ID) credential.password else null
+            preferences.getString(API_KEY_PREFERENCE_KEY, null)
         }
     }
 
     override suspend fun invalidateApiKey(baseUrl: String): Result<Unit> {
         return runCatching {
-            markInvalidated(baseUrl, true)
-            credentialManager.clearCredentialState(ClearCredentialStateRequest())
+            preferences.edit().remove(API_KEY_PREFERENCE_KEY).apply()
             Unit
         }
     }
 
-    private fun isInvalidated(baseUrl: String): Boolean {
-        return invalidatedPreferences.getBoolean(baseUrl.invalidatedKey(), false)
-    }
-
-    private fun markInvalidated(baseUrl: String, invalidated: Boolean) {
-        invalidatedPreferences.edit().putBoolean(baseUrl.invalidatedKey(), invalidated).apply()
-    }
-
-    private fun String.invalidatedKey(): String = "invalidated:$this"
-
     private companion object {
-        private const val INVALIDATED_PREFS_NAME = "kanbn_invalidated_api_keys"
-        private const val CREDENTIAL_ID = "space.hackenslacker.kanbn4droid.api_key"
+        private const val PREFERENCES_NAME = "kanbn_api_key_store"
+        private const val API_KEY_PREFERENCE_KEY = "api_key"
     }
 }

app/src/main/java/space/hackenslacker/kanbn4droid/app/auth/AuthResult.kt

@@ -1,18 +1,39 @@
 package space.hackenslacker.kanbn4droid.app.auth
 
+import java.io.IOException
+import java.net.ConnectException
 import java.net.SocketTimeoutException
 import java.net.UnknownHostException
 
+enum class AuthFailureReason {
+    Authentication,
+    Connectivity,
+    Server,
+    Unexpected,
+}
+
 sealed interface AuthResult {
     data object Success : AuthResult
-    data class Failure(val message: String) : AuthResult
+    data class Failure(
+        val message: String,
+        val reason: AuthFailureReason,
+    ) : AuthResult
 }
 
 object AuthErrorMapper {
     fun fromHttpCode(code: Int): AuthResult.Failure {
         return when (code) {
-            401, 403 -> AuthResult.Failure("Authentication failed. Check your API key.")
-            else -> AuthResult.Failure("Server error: $code")
+            401,
+            403,
+            -> AuthResult.Failure(
+                message = "Authentication failed. Check your API key.",
+                reason = AuthFailureReason.Authentication,
+            )
+
+            else -> AuthResult.Failure(
+                message = "Server error: $code",
+                reason = AuthFailureReason.Server,
+            )
         }
     }
 
@@ -20,9 +41,17 @@ object AuthErrorMapper {
         return when (throwable) {
             is SocketTimeoutException,
             is UnknownHostException,
-            -> AuthResult.Failure("Cannot reach server. Check your connection and URL.")
+            is ConnectException,
+            is IOException,
+            -> AuthResult.Failure(
+                message = "Cannot reach server. Check your connection and URL.",
+                reason = AuthFailureReason.Connectivity,
+            )
 
-            else -> AuthResult.Failure("Unexpected error. Please try again.")
+            else -> AuthResult.Failure(
+                message = "Unexpected error. Please try again.",
+                reason = AuthFailureReason.Unexpected,
+            )
         }
     }
 }