Merge pull request #160 from steemit/stream-irreversible-block

Add `mode` param on streaming method to load head or irreversible block

src/api/index.js

@@ -265,7 +265,11 @@ class Steem extends EventEmitter {
     return this.currentP;
   }
 
-  streamBlockNumber(callback, ts = 200) {
+  streamBlockNumber(mode = 'head', callback, ts = 200) {
+    if (typeof mode === 'function') {
+      callback = mode;
+      mode = 'head';
+    }
     let current = '';
     let running = true;
 
@@ -274,10 +278,22 @@ class Steem extends EventEmitter {
 
       this.getDynamicGlobalPropertiesAsync()
         .then((result) => {
-          const blockId = result.head_block_number;
+          const blockId = mode === 'irreversible'
+            ? result.last_irreversible_block_num
+            : result.head_block_number;
+
           if (blockId !== current) {
-            current = blockId;
-            callback(null, current);
+            if (current) {
+              for (let i = current; i < blockId; i++) {
+                if (i !== current) {
+                  callback(null, i);
+                }
+                current = i;
+              }
+            } else {
+              current = blockId;
+              callback(null, blockId);
+            }
           }
 
           Promise.delay(ts).then(() => {
@@ -295,11 +311,16 @@ class Steem extends EventEmitter {
     };
   }
 
-  streamBlock(callback) {
+  streamBlock(mode = 'head', callback) {
+    if (typeof mode === 'function') {
+      callback = mode;
+      mode = 'head';
+    }
+
     let current = '';
     let last = '';
 
-    const release = this.streamBlockNumber((err, id) => {
+    const release = this.streamBlockNumber(mode, (err, id) => {
       if (err) {
         release();
         callback(err);
@@ -316,8 +337,13 @@ class Steem extends EventEmitter {
     return release;
   }
 
-  streamTransactions(callback) {
-    const release = this.streamBlock((err, result) => {
+  streamTransactions(mode = 'head', callback) {
+    if (typeof mode === 'function') {
+      callback = mode;
+      mode = 'head';
+    }
+
+    const release = this.streamBlock(mode, (err, result) => {
       if (err) {
         release();
         callback(err);
@@ -334,8 +360,13 @@ class Steem extends EventEmitter {
     return release;
   }
 
-  streamOperations(callback) {
-    const release = this.streamTransactions((err, transaction) => {
+  streamOperations(mode = 'head', callback) {
+    if (typeof mode === 'function') {
+      callback = mode;
+      mode = 'head';
+    }
+
+    const release = this.streamTransactions(mode, (err, transaction) => {
       if (err) {
         release();
         callback(err);