implements transaction subscription

.gitignore

@@ -4,3 +4,4 @@ debug.log
 error.log
 .DS_Store
 hosts.cache
+*.mdb

examples/subscribe.js

@@ -39,8 +39,26 @@ async function main() {
         return true;
     });
 
-    while (running_) {
+    node.chain.subscribeTransaction((e, tx) => {
+        if (e !== kth.errors.success) {
+            console.log(`Error: ${e}`);
+            return false;
+        }
+
+        if ( ! running_) {
+            return false;
+        }
 
+
+        if (tx !== null) {
+            console.log("Received Transaction: ", tx);
+        }
+
+        return true;
+    });
+
+
+    while (running_) {
         await sleep(1000);
     }
 

examples/subscribe_multiple.js

@@ -45,6 +45,38 @@ const onBlockArrivedGenerator = (n) => {
     }
 }
 
+const onTransactionArrivedGenerator = (n) => {
+    return (e, tx) => {
+        console.log(`onTransactionArrivedGenerator - `, n, e, tx);
+
+        if (e !== kth.errors.success) {
+            console.log(`Error: ${e}`);
+            return false;
+        }
+
+        if ( ! running_) {
+            return false;
+        }
+
+        if (tx !== null) {
+            console.log("Transaction received: ", tx);
+        }
+
+        if (n >= max.length) {
+            console.log("n >= max.length");
+            return false;
+        }
+
+        count[n] += 1;
+        if (count[n] >= max[n]) {
+            console.log("count[n] >= max[n]");
+            return false;
+        }
+
+        return true;
+    }
+}
+
 async function main() {
     process.on('SIGINT', shutdown);
     const config = kth.settings.getDefault(kth.network.chipnet);
@@ -64,6 +96,17 @@ async function main() {
     node.chain.subscribeBlockchain(onBlockArrivedGenerator(8));
     node.chain.subscribeBlockchain(onBlockArrivedGenerator(9));
 
+    node.chain.subscribeTransaction(onTransactionArrivedGenerator(0));
+    node.chain.subscribeTransaction(onTransactionArrivedGenerator(1));
+    node.chain.subscribeTransaction(onTransactionArrivedGenerator(2));
+    node.chain.subscribeTransaction(onTransactionArrivedGenerator(3));
+    node.chain.subscribeTransaction(onTransactionArrivedGenerator(4));
+    node.chain.subscribeTransaction(onTransactionArrivedGenerator(5));
+    node.chain.subscribeTransaction(onTransactionArrivedGenerator(6));
+    node.chain.subscribeTransaction(onTransactionArrivedGenerator(7));
+    node.chain.subscribeTransaction(onTransactionArrivedGenerator(8));
+    node.chain.subscribeTransaction(onTransactionArrivedGenerator(9));
+
     while (running_) {
         await sleep(1000);
     }

package.json

@@ -39,7 +39,7 @@
   "homepage": "https://github.com/k-nuth/js-api#readme",
   "dependencies": {
     "bluebird": "^3.7.2",
-    "@knuth/bch-native": "^0.56.0",
+    "@knuth/bch-native": "^0.57.0",
     "memoizee": "^0.4.14"
   },
   "devDependencies": {

src/chain/chain.js

@@ -103,6 +103,10 @@ const async_chain = {
     subscribe_blockchain: (...args) => {
         kth.chain_subscribe_blockchain(...args);
     },
+    subscribe_transaction: (...args) => {
+        kth.chain_subscribe_transaction(...args);
+    },
+
 };
 
 function objOrNull(ec, native, fromNative) {
@@ -116,6 +120,8 @@ class Chain {
         this.nodeNative = nodeNative;
         this.blockchainSubscribers = [];
         this.blockAlreadySubscribed = false;
+        this.transactionSubscribers = [];
+        this.transactionAlreadySubscribed = false;
     }
 
     async getLastHeight() {
@@ -202,6 +208,27 @@ class Chain {
         });
     }
 
+    subscribeTransaction(callback) {
+        this.transactionSubscribers.push(callback);
+        if (this.transactionAlreadySubscribed) {
+            return;
+        }
+        this.transactionAlreadySubscribed = true;
+
+        async_chain.subscribe_transaction(this.nodeNative, this.native, (error, tx) => {
+            if (tx !== null) {
+                tx = tx.fromNative(tx);
+            }
+
+            for (const subscriber of [...this.transactionSubscribers]) {
+                if ( ! subscriber(error, tx)) {
+                    this.transactionSubscribers = this.transactionSubscribers.filter(s => s !== subscriber);
+                }
+            }
+            return true;
+        });
+    }
+
     //TODO(fernando): Merkle Block
     //TODO(fernando): Compact Block
     //TODO(fernando): Spend Block