make LevelDb node aware of db ready/not ready to reduce errors.

storage/leveldb/67-leveldb.js

@@ -1,5 +1,5 @@
 /**
- * Copyright 2013 IBM Corp.
+ * Copyright 2013,2015 IBM Corp.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,13 +21,19 @@ module.exports = function(RED) {
     function LevelNode(n) {
         RED.nodes.createNode(this,n);
         this.dbname = n.db;
+        this.ready = false;
         var node = this;
         lvldb(this.dbname, function(err, db) {
             if (err) { node.error(err); }
             node.db = db;
+            node.db.on('ready', function() { node.ready = true; });
+            node.db.on('closing', function() { node.ready = false; });
         });
-        this.on('close', function() {
-            if (node.db) { node.db.close(); }
+        node.on('close', function() {
+            if (node.db) {
+                node.ready = false;
+                node.db.close();
+            }
         });
     }
     RED.nodes.registerType("leveldbase",LevelNode);
@@ -38,9 +44,9 @@ module.exports = function(RED) {
         this.level = n.level;
         this.levelConfig = RED.nodes.getNode(this.level);
 
-        if (this.levelConfig) {
-            var node = this;
-            node.on("input", function(msg) {
+        var node = this;
+        node.on("input", function(msg) {
+            if (node.levelConfig && node.levelConfig.ready) {
                 var key = msg.topic.toString();
                 if (key && (key.length > 0)) {
                     node.levelConfig.db.get(msg.topic, function(err, value) {
@@ -53,14 +59,10 @@ module.exports = function(RED) {
                         node.send(msg);
                     });
                 }
-                else {
-                    node.error("Cannot make key string from msg.topic");
-                }
-            });
-        }
-        else {
-            this.error("LevelDB database name not configured");
-        }
+                else { node.error("Cannot make key string from msg.topic"); }
+            }
+            else { node.warn("Database not ready"); }
+        });
     }
     RED.nodes.registerType("leveldb in",LevelDBNodeIn);
 
@@ -71,9 +73,9 @@ module.exports = function(RED) {
         this.operation = n.operation;
         this.levelConfig = RED.nodes.getNode(this.level);
 
-        if (this.levelConfig) {
-            var node = this;
-            node.on("input", function(msg) {
+        var node = this;
+        node.on("input", function(msg) {
+            if (node.levelConfig && node.levelConfig.ready) {
                 var key = msg.topic.toString();
                 if (key && (key.length > 0)) {
                     if (node.operation === "delete") {
@@ -85,14 +87,10 @@ module.exports = function(RED) {
                         });
                     }
                 }
-                else {
-                    node.error("Cannot make key string from msg.topic");
-                }
-            });
-        }
-        else {
-            this.error("LevelDB database name not configured");
-        }
+                else { node.error("Cannot make key string from msg.topic"); }
+            }
+            else { node.warn("Database not ready"); }
+        });
     }
     RED.nodes.registerType("leveldb out",LevelDBNodeOut);
 }

storage/leveldb/package.json

@@ -1,9 +1,9 @@
 {
     "name"          : "node-red-node-leveldb",
-    "version"       : "0.0.2",
+    "version"       : "0.0.3",
     "description"   : "A Node-RED node to read and write to a LevelDB database",
     "dependencies"  : {
-        "level"   : "0.18.0"
+        "level"   : "1.0.0"
     },
     "repository" : {
         "type":"git",