[#743] Add API for reading memos

CHANGELOG.md

@@ -9,6 +9,7 @@ Change Log
   - `Synchronizer.getLegacySaplingAddress`
   - `Synchronizer.getLegacyTransparentAddress`
   - `Synchronizer.isValidUnifiedAddr`
+  - `Synchronizer.getMemos(TransactionOverview)`
 - `cash.z.ecc.android.sdk.model`:
   - `Account`
   - `FirstClassByteArray`

sdk-lib/src/main/java/cash/z/ecc/android/sdk/SdkSynchronizer.kt

@@ -45,6 +45,7 @@ import cash.z.ecc.android.sdk.model.Account
 import cash.z.ecc.android.sdk.model.BlockHeight
 import cash.z.ecc.android.sdk.model.LightWalletEndpoint
 import cash.z.ecc.android.sdk.model.PendingTransaction
+import cash.z.ecc.android.sdk.model.TransactionOverview
 import cash.z.ecc.android.sdk.model.UnifiedSpendingKey
 import cash.z.ecc.android.sdk.model.WalletBalance
 import cash.z.ecc.android.sdk.model.Zatoshi
@@ -74,8 +75,10 @@ import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.flow.filterNotNull
 import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.flow.launchIn
+import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.flow.onEach
 import kotlinx.coroutines.launch
 import kotlin.coroutines.CoroutineContext
@@ -99,7 +102,8 @@ import kotlin.coroutines.EmptyCoroutineContext
 class SdkSynchronizer internal constructor(
     private val storage: DerivedDataRepository,
     private val txManager: OutboundTransactionManager,
-    val processor: CompactBlockProcessor
+    val processor: CompactBlockProcessor,
+    private val rustBackend: RustBackend
 ) : Synchronizer {
 
     // pools
@@ -318,6 +322,21 @@ class SdkSynchronizer internal constructor(
         processor.quickRewind()
     }
 
+    override fun getMemos(transactionOverview: TransactionOverview): Flow<String> {
+        return when (transactionOverview.isSentTransaction) {
+            true -> {
+                val sentNoteIds = storage.getSentNoteIds(transactionOverview.id)
+
+                sentNoteIds.map { rustBackend.getSentMemoAsUtf8(it) }.filterNotNull()
+            }
+            false -> {
+                val receivedNoteIds = storage.getReceivedNoteIds(transactionOverview.id)
+
+                receivedNoteIds.map { rustBackend.getReceivedMemoAsUtf8(it) }.filterNotNull()
+            }
+        }
+    }
+
     //
     // Storage APIs
     //
@@ -708,12 +727,14 @@ internal object DefaultSynchronizerFactory {
     fun new(
         repository: DerivedDataRepository,
         txManager: OutboundTransactionManager,
-        processor: CompactBlockProcessor
+        processor: CompactBlockProcessor,
+        rustBackend: RustBackend
     ): Synchronizer {
         return SdkSynchronizer(
             repository,
             txManager,
-            processor
+            processor,
+            rustBackend
         )
     }
 

sdk-lib/src/main/java/cash/z/ecc/android/sdk/Synchronizer.kt

@@ -359,6 +359,11 @@ interface Synchronizer {
 
     suspend fun quickRewind()
 
+    /**
+     * Returns a list of memos for a transaction.
+     */
+    fun getMemos(transactionOverview: TransactionOverview): Flow<String>
+
     //
     // Error Handling
     //
@@ -547,7 +552,8 @@ interface Synchronizer {
             return SdkSynchronizer(
                 repository,
                 txManager,
-                processor
+                processor,
+                rustBackend
             )
         }
 

sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/DbDerivedDataRepository.kt

@@ -63,6 +63,11 @@ internal class DbDerivedDataRepository(
     override val allTransactions: Flow<List<TransactionOverview>>
         get() = invalidatingFlow.map { derivedDataDb.allTransactionView.getAllTransactions().toList() }
 
+    override fun getSentNoteIds(transactionId: Long) = derivedDataDb.sentNotesTable.getSentNoteIds(transactionId)
+
+    override fun getReceivedNoteIds(transactionId: Long) =
+        derivedDataDb.receivedNotesTable.getReceivedNoteIds(transactionId)
+
     override suspend fun close() {
         derivedDataDb.close()
     }

sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/DerivedDataDb.kt

@@ -13,7 +13,7 @@ import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
 
 internal class DerivedDataDb private constructor(
-    private val zcashNetwork: ZcashNetwork,
+    zcashNetwork: ZcashNetwork,
     private val sqliteDatabase: SupportSQLiteDatabase
 ) {
     val accountTable = AccountTable(sqliteDatabase)
@@ -28,6 +28,10 @@ internal class DerivedDataDb private constructor(
 
     val receivedTransactionView = ReceivedTransactionView(zcashNetwork, sqliteDatabase)
 
+    val sentNotesTable = SentNoteTable(zcashNetwork, sqliteDatabase)
+
+    val receivedNotesTable = ReceivedNoteTable(zcashNetwork, sqliteDatabase)
+
     suspend fun close() {
         withContext(Dispatchers.IO) {
             sqliteDatabase.close()

sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/ReceivedNoteTable.kt

@@ -0,0 +1,68 @@
+package cash.z.ecc.android.sdk.internal.db.derived
+
+import androidx.sqlite.db.SupportSQLiteDatabase
+import cash.z.ecc.android.sdk.internal.db.queryAndMap
+import cash.z.ecc.android.sdk.model.ZcashNetwork
+import java.util.Locale
+
+internal class ReceivedNoteTable(
+    @Suppress("UnusedPrivateMember")
+    private val zcashNetwork: ZcashNetwork,
+    private val sqliteDatabase: SupportSQLiteDatabase
+) {
+    companion object {
+
+        private val ORDER_BY = String.format(
+            Locale.ROOT,
+            "%s ASC", // $NON-NLS
+            ReceivedNoteTableDefinition.COLUMN_INTEGER_ID
+        )
+
+        private val PROJECTION_ID = arrayOf(ReceivedNoteTableDefinition.COLUMN_INTEGER_ID)
+
+        private val SELECT_BY_TRANSACTION_ID = String.format(
+            Locale.ROOT,
+            "%s = ?", // $NON-NLS
+            ReceivedNoteTableDefinition.COLUMN_INTEGER_TRANSACTION_ID
+        )
+    }
+
+    fun getReceivedNoteIds(transactionId: Long) =
+        sqliteDatabase.queryAndMap(
+            table = ReceivedNoteTableDefinition.TABLE_NAME,
+            columns = PROJECTION_ID,
+            selection = SELECT_BY_TRANSACTION_ID,
+            selectionArgs = arrayOf(transactionId),
+            orderBy = ORDER_BY,
+            cursorParser = {
+                val idColumnIndex = it.getColumnIndex(ReceivedNoteTableDefinition.COLUMN_INTEGER_ID)
+
+                it.getLong(idColumnIndex)
+            }
+        )
+}
+
+// https://github.com/zcash/librustzcash/blob/277d07c79c7a08907b05a6b29730b74cdb238b97/zcash_client_sqlite/src/wallet/init.rs#L364
+internal object ReceivedNoteTableDefinition {
+    const val TABLE_NAME = "received_notes" // $NON-NLS
+
+    const val COLUMN_INTEGER_ID = "id_note" // $NON-NLS
+
+    const val COLUMN_INTEGER_TRANSACTION_ID = "tx" // $NON-NLS
+
+    const val COLUMN_INTEGER_OUTPUT_INDEX = "output_index" // $NON-NLS
+
+    const val COLUMN_INTEGER_ACCOUNT = "account" // $NON-NLS
+
+    const val COLUMN_BLOB_DIVERSIFIER = "diversifier" // $NON-NLS
+
+    const val COLUMN_INTEGER_VALUE = "value" // $NON-NLS
+
+    const val COLUMN_BLOB_RCM = "rcm" // $NON-NLS
+
+    const val COLUMN_BLOB_NF = "nf" // $NON-NLS
+
+    const val COLUMN_BLOB_MEMO = "memo" // $NON-NLS
+
+    const val COLUMN_INTEGER_SPENT = "spent" // $NON-NLS
+}

sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/ReceivedTransactionView.kt

@@ -28,7 +28,7 @@ internal class ReceivedTransactionView(
     }
 
     suspend fun count() = sqliteDatabase.queryAndMap(
-        AccountTableDefinition.TABLE_NAME,
+        ReceivedTransactionViewDefinition.VIEW_NAME,
         columns = PROJECTION_COUNT,
         cursorParser = { it.getLong(0) }
     ).first()

sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/SentNoteTable.kt

@@ -0,0 +1,66 @@
+package cash.z.ecc.android.sdk.internal.db.derived
+
+import androidx.sqlite.db.SupportSQLiteDatabase
+import cash.z.ecc.android.sdk.internal.db.queryAndMap
+import cash.z.ecc.android.sdk.model.ZcashNetwork
+import java.util.Locale
+
+internal class SentNoteTable(
+    @Suppress("UnusedPrivateMember")
+    private val zcashNetwork: ZcashNetwork,
+    private val sqliteDatabase: SupportSQLiteDatabase
+) {
+    companion object {
+
+        private val ORDER_BY = String.format(
+            Locale.ROOT,
+            "%s ASC", // $NON-NLS
+            SentNoteTableDefinition.COLUMN_INTEGER_ID
+        )
+
+        private val PROJECTION_ID = arrayOf(SentNoteTableDefinition.COLUMN_INTEGER_ID)
+
+        private val SELECT_BY_TRANSACTION_ID = String.format(
+            Locale.ROOT,
+            "%s = ?", // $NON-NLS
+            SentNoteTableDefinition.COLUMN_INTEGER_TRANSACTION_ID
+        )
+    }
+
+    fun getSentNoteIds(transactionId: Long) =
+        sqliteDatabase.queryAndMap(
+            table = SentNoteTableDefinition.TABLE_NAME,
+            columns = PROJECTION_ID,
+            selection = SELECT_BY_TRANSACTION_ID,
+            selectionArgs = arrayOf(transactionId),
+            orderBy = ORDER_BY,
+            cursorParser = {
+                val idColumnIndex = it.getColumnIndex(SentNoteTableDefinition.COLUMN_INTEGER_ID)
+
+                it.getLong(idColumnIndex)
+            }
+        )
+}
+
+// https://github.com/zcash/librustzcash/blob/277d07c79c7a08907b05a6b29730b74cdb238b97/zcash_client_sqlite/src/wallet/init.rs#L393
+internal object SentNoteTableDefinition {
+    const val TABLE_NAME = "sent_notes" // $NON-NLS
+
+    const val COLUMN_INTEGER_ID = "id_note" // $NON-NLS
+
+    const val COLUMN_INTEGER_TRANSACTION_ID = "tx" // $NON-NLS
+
+    const val COLUMN_INTEGER_OUTPUT_POOL = "output_pool" // $NON-NLS
+
+    const val COLUMN_INTEGER_OUTPUT_INDEX = "output_index" // $NON-NLS
+
+    const val COLUMN_INTEGER_FROM_ACCOUNT = "from_account" // $NON-NLS
+
+    const val COLUMN_STRING_TO_ADDRESS = "to_address" // $NON-NLS
+
+    const val COLUMN_INTEGER_TO_ACCOUNT = "to_account" // $NON-NLS
+
+    const val COLUMN_INTEGER_VALUE = "value" // $NON-NLS
+
+    const val COLUMN_BLOB_MEMO = "memo" // $NON-NLS
+}

sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/repository/DerivedDataRepository.kt

@@ -104,5 +104,9 @@ internal interface DerivedDataRepository {
     /** A flow of all the inbound and outbound confirmed transactions */
     val allTransactions: Flow<List<TransactionOverview>>
 
+    fun getSentNoteIds(transactionId: Long): Flow<Long>
+
+    fun getReceivedNoteIds(transactionId: Long): Flow<Long>
+
     suspend fun close()
 }

sdk-lib/src/main/java/cash/z/ecc/android/sdk/jni/RustBackend.kt

@@ -441,14 +441,14 @@ internal class RustBackend private constructor(
             dbDataPath: String,
             idNote: Long,
             networkId: Int
-        ): String
+        ): String?
 
         @JvmStatic
         private external fun getSentMemoAsUtf8(
             dbDataPath: String,
             dNote: Long,
             networkId: Int
-        ): String
+        ): String?
 
         @JvmStatic
         private external fun validateCombinedChain(

sdk-lib/src/main/java/cash/z/ecc/android/sdk/jni/RustBackendWelding.kt

@@ -64,9 +64,9 @@ internal interface RustBackendWelding {
 
     fun getBranchIdForHeight(height: BlockHeight): Long
 
-    suspend fun getReceivedMemoAsUtf8(idNote: Long): String
+    suspend fun getReceivedMemoAsUtf8(idNote: Long): String?
 
-    suspend fun getSentMemoAsUtf8(idNote: Long): String
+    suspend fun getSentMemoAsUtf8(idNote: Long): String?
 
     suspend fun getVerifiedBalance(account: Int = 0): Zatoshi
 

sdk-lib/src/main/java/cash/z/ecc/android/sdk/model/TransactionOverview.kt

@@ -5,8 +5,8 @@ package cash.z.ecc.android.sdk.model
  *
  * Note that both sent and received transactions will have a positive net value.  Consumers of this class must
  */
-data class TransactionOverview(
+data class TransactionOverview internal constructor(
-    val id: Long,
+    internal val id: Long,
     val rawId: FirstClassByteArray,
     val minedHeight: BlockHeight,
     val expiryHeight: BlockHeight,