From 4276420a533954ecbc8da33b330008e45dbd24e8 Mon Sep 17 00:00:00 2001
From: Jaco Greeff <jacogr@gmail.com>
Date: Wed, 13 Mar 2019 18:04:00 +0100
Subject: [PATCH] TxDb.transactionAsync to  (await for transactions) (#360)

---
 packages/db/src/engines/TransactionDb.ts | 22 ++++++++++++++++++++++
 packages/db/src/types.ts                 |  1 +
 packages/trie-db/src/index.ts            | 20 ++++++++++++++++++++
 3 files changed, 43 insertions(+)

diff --git a/packages/db/src/engines/TransactionDb.ts b/packages/db/src/engines/TransactionDb.ts
index 79f843717..f4572c8bc 100644
--- a/packages/db/src/engines/TransactionDb.ts
+++ b/packages/db/src/engines/TransactionDb.ts
@@ -26,6 +26,28 @@ export default class TransactionDb implements TxDb {
     this.txStarted = false;
   }
 
+  async transactionAsync<T> (fn: () => Promise<T>): Promise<T> {
+    l.debug(() => ['transactionAsync']);
+
+    try {
+      this.createTx();
+
+      const result = await fn();
+
+      if (result) {
+        this.commitTx();
+      } else {
+        this.revertTx();
+      }
+
+      return result;
+    } catch (error) {
+      this.revertTx();
+
+      throw error;
+    }
+  }
+
   transaction<T> (fn: () => T): T {
     l.debug(() => ['transaction']);
 
diff --git a/packages/db/src/types.ts b/packages/db/src/types.ts
index ca92c5711..12f7dcc0c 100644
--- a/packages/db/src/types.ts
+++ b/packages/db/src/types.ts
@@ -34,5 +34,6 @@ export interface BaseDb {
 }
 
 export interface TxDb extends BaseDb {
+  transactionAsync <T> (fn: () => Promise<T>): Promise<T>;
   transaction <T> (fn: () => T): T;
 }
diff --git a/packages/trie-db/src/index.ts b/packages/trie-db/src/index.ts
index f6fcef9c6..54b26b37e 100644
--- a/packages/trie-db/src/index.ts
+++ b/packages/trie-db/src/index.ts
@@ -31,6 +31,26 @@ export default class Trie extends Impl implements TrieDb {
     l.log(`Created with ${this.codec.type} codec, root ${u8aToHex(this.rootHash, 64)}`);
   }
 
+  async transactionAsync<T> (fn: () => Promise<T>): Promise<T> {
+    try {
+      this.createCheckpoint();
+
+      const result = await this.db.transactionAsync(fn);
+
+      if (result) {
+        this.commitCheckpoint();
+      } else {
+        this.revertCheckpoint();
+      }
+
+      return result;
+    } catch (error) {
+      this.revertCheckpoint();
+
+      throw error;
+    }
+  }
+
   transaction<T> (fn: () => T): T {
     try {
       this.createCheckpoint();