blockchain height endpoint

lib/blockchainexplorers/insight.js

@@ -168,6 +168,20 @@ Insight.prototype.estimateFee = function(nbBlocks, cb) {
   });
 };
 
+Insight.prototype.getBlockchainHeight = function(cb) {
+  var path = this.apiPrefix + '/sync';
+
+  var args = {
+    method: 'GET',
+    path: path,
+    json: true,
+  };
+  this._doRequest(args, function(err, res, body) {
+    if (err || res.statusCode !== 200) return cb(_parseErr(err, res));
+    return cb(null, body.blockChainHeight);
+  });
+};
+
 Insight.prototype.initSocket = function() {
 
   // sockets always use the first server on the pull