TxDb.transactionAsync to (await for transactions) (#360)

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']);
 

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;
 }

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();