Merged in temporary-fix-inmemory-wallet-thread-clash (pull request #184)

Temporary fix inmemory wallet thread clash

core/src/main/kotlin/com/r3corda/core/node/services/Services.kt

@@ -23,7 +23,11 @@ val TOPIC_DEFAULT_POSTFIX = ".0"
  * change out from underneath you, even though the canonical currently-best-known wallet may change as we learn
  * about new transactions from our peers and generate new transactions that consume states ourselves.
  *
- * This absract class has no references to Cash contracts.
+ * This abstract class has no references to Cash contracts.
+ *
+ * [states] Holds the list of states that are *active* and *relevant*.
+ *   Active means they haven't been consumed yet (or we don't know about it).
+ *   Relevant means they contain at least one of our pubkeys
  */
 class Wallet(val states: List<StateAndRef<ContractState>>) {
     @Suppress("UNCHECKED_CAST")

core/src/main/kotlin/com/r3corda/core/testing/AlwaysSucceedContract.kt

@@ -0,0 +1,10 @@
+package com.r3corda.core.testing
+
+import com.r3corda.core.contracts.Contract
+import com.r3corda.core.contracts.TransactionForContract
+import com.r3corda.core.crypto.SecureHash
+
+class AlwaysSucceedContract(override val legalContractReference: SecureHash = SecureHash.sha256("Always succeed contract")) : Contract {
+    override fun verify(tx: TransactionForContract) {
+    }
+}

core/src/main/kotlin/com/r3corda/core/testing/DummyLinearState.kt

@@ -0,0 +1,18 @@
+package com.r3corda.core.testing
+
+import com.r3corda.core.contracts.Contract
+import com.r3corda.core.contracts.LinearState
+import com.r3corda.core.crypto.SecureHash
+import java.security.PublicKey
+import java.util.*
+
+class DummyLinearState(
+        override val thread: SecureHash = SecureHash.randomSHA256(),
+        override val contract: Contract = AlwaysSucceedContract(),
+        override val participants: List<PublicKey> = listOf(),
+        val nonce: SecureHash = SecureHash.randomSHA256()) : LinearState {
+
+    override fun isRelevant(ourKeys: Set<PublicKey>): Boolean {
+        return participants.any { ourKeys.contains(it) }
+    }
+}

core/src/main/kotlin/com/r3corda/core/testing/InMemoryWalletService.kt

@@ -22,6 +22,8 @@ import javax.annotation.concurrent.ThreadSafe
  */
 @ThreadSafe
 open class InMemoryWalletService(private val services: ServiceHub) : SingletonSerializeAsToken(), WalletService {
+    class ClashingThreads(threads: Set<SecureHash>, transactions: Iterable<WireTransaction>) :
+            Exception("There are multiple linear head states after processing transactions $transactions. The clashing thread(s): $threads")
     private val log = loggerFor<InMemoryWalletService>()
 
     // Variables inside InnerState are protected with a lock by the ThreadBox and aren't in scope unless you're
@@ -44,7 +46,7 @@ open class InMemoryWalletService(private val services: ServiceHub) : SingletonSe
      * Returns a snapshot of the heads of LinearStates
      */
     override val linearHeads: Map<SecureHash, StateAndRef<LinearState>>
-        get() = mutex.locked { wallet }.let { wallet ->
+        get() = currentWallet.let { wallet ->
             wallet.states.filterStatesOfType<LinearState>().associateBy { it.state.data.thread }.mapValues { it.value }
         }
 
@@ -74,10 +76,17 @@ open class InMemoryWalletService(private val services: ServiceHub) : SingletonSe
                 val combinedDelta = delta + walletAndDelta.second
                 Pair(wallet, combinedDelta)
             }
+
+            val clashingThreads = walletAndNetDelta.first.clashingThreads
+            if (!clashingThreads.isEmpty()) {
+                throw ClashingThreads(clashingThreads, txns)
+            }
+
             wallet = walletAndNetDelta.first
             netDelta = walletAndNetDelta.second
             return@locked wallet
         }
+
         if (netDelta != Wallet.NoUpdate) {
             _updatesPublisher.onNext(netDelta)
         }
@@ -120,4 +129,23 @@ open class InMemoryWalletService(private val services: ServiceHub) : SingletonSe
 
         return Pair(Wallet(newStates), change)
     }
-}
+
+    companion object {
+
+        // Returns the set of LinearState threads that clash in the wallet
+        val Wallet.clashingThreads: Set<SecureHash> get() {
+            val clashingThreads = HashSet<SecureHash>()
+            val threadsSeen = HashSet<SecureHash>()
+            for (linearState in states.filterStatesOfType<LinearState>()) {
+                val thread = linearState.state.data.thread
+                if (threadsSeen.contains(thread)) {
+                    clashingThreads.add(thread)
+                } else {
+                    threadsSeen.add(thread)
+                }
+            }
+            return clashingThreads
+        }
+
+    }
+}

node/src/test/kotlin/com/r3corda/node/services/WalletWithCashTest.kt

@@ -4,6 +4,7 @@ import com.r3corda.contracts.cash.Cash
 import com.r3corda.contracts.cash.cashBalances
 import com.r3corda.contracts.testing.fillWithSomeTestCash
 import com.r3corda.core.contracts.*
+import com.r3corda.core.crypto.SecureHash
 import com.r3corda.core.node.ServiceHub
 import com.r3corda.core.node.services.testing.MockKeyManagementService
 import com.r3corda.core.node.services.testing.MockStorageService
@@ -14,6 +15,7 @@ import com.r3corda.node.services.wallet.NodeWalletService
 import org.junit.After
 import org.junit.Before
 import org.junit.Test
+import org.assertj.core.api.Assertions.assertThatThrownBy;
 import java.util.*
 import kotlin.test.assertEquals
 import kotlin.test.assertNull
@@ -96,4 +98,62 @@ class WalletWithCashTest {
 
         // TODO: Flesh out these tests as needed.
     }
+
+
+    @Test
+    fun branchingLinearStatesFails() {
+        val (wallet, services) = make()
+
+        val freshKey = services.keyManagementService.freshKey()
+
+        val thread = SecureHash.sha256("thread")
+
+        // Issue a linear state
+        val dummyIssue = TransactionType.General.Builder(notary = DUMMY_NOTARY).apply {
+            addOutputState(DummyLinearState(thread = thread, participants = listOf(freshKey.public)))
+            signWith(freshKey)
+        }.toSignedTransaction()
+
+        wallet.notify(dummyIssue.tx)
+        assertEquals(1, wallet.currentWallet.states.size)
+
+        // Issue another linear state of the same thread (nonce different)
+        val dummyIssue2 = TransactionType.General.Builder(notary = DUMMY_NOTARY).apply {
+            addOutputState(DummyLinearState(thread = thread, participants = listOf(freshKey.public)))
+            signWith(freshKey)
+        }.toSignedTransaction()
+
+        assertThatThrownBy {
+            wallet.notify(dummyIssue2.tx)
+        }
+        assertEquals(1, wallet.currentWallet.states.size)
+    }
+
+    @Test
+    fun sequencingLinearStatesWorks() {
+        val (wallet, services) = make()
+
+        val freshKey = services.keyManagementService.freshKey()
+
+        val thread = SecureHash.sha256("thread")
+
+        // Issue a linear state
+        val dummyIssue = TransactionType.General.Builder(notary = DUMMY_NOTARY).apply {
+            addOutputState(DummyLinearState(thread = thread, participants = listOf(freshKey.public)))
+            signWith(freshKey)
+        }.toSignedTransaction()
+
+        wallet.notify(dummyIssue.tx)
+        assertEquals(1, wallet.currentWallet.states.size)
+
+        // Move the same state
+        val dummyMove = TransactionType.General.Builder(notary = DUMMY_NOTARY).apply {
+            addOutputState(DummyLinearState(thread = thread, participants = listOf(freshKey.public)))
+            addInputState(dummyIssue.tx.outRef<LinearState>(0))
+            signWith(DUMMY_NOTARY_KEY)
+        }.toSignedTransaction()
+
+        wallet.notify(dummyMove.tx)
+        assertEquals(1, wallet.currentWallet.states.size)
+    }
 }