Add LevelDB node to the mix - a file based key value store... persistent across reboots etc.

nodes/storage/67-leveldb.html

@@ -0,0 +1,114 @@
+<!--
+  Copyright 2013 IBM Corp.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+-->
+
+<script type="text/x-red" data-template-name="leveldbase">
+	<div class="form-row">
+		<label for="node-config-input-db"><i class="icon-briefcase"></i> Database</label>
+		<input type="text" id="node-config-input-db" placeholder="database path/name">
+	</div>
+</script>
+
+<script type="text/javascript">
+	RED.nodes.registerType('leveldbase',{
+		category: 'config',
+		defaults: {
+			db: {value:"",required:true}
+		},
+		label: function() {
+			return this.db;
+		}
+	});
+</script>
+
+<script type="text/x-red" data-template-name="leveldb in">
+	<div class="form-row node-input-level">
+		<label for="node-input-level"><i class="icon-briefcase"></i> Database</label>
+		<input type="text" id="node-input-level">
+	</div>
+	<div class="form-row">
+		<label for="node-input-name"><i class="icon-tag"></i> Name</label>
+		<input type="text" id="node-input-name" placeholder="Name">
+	</div>
+</script>
+
+<script type="text/x-red" data-help-name="leveldb in">
+	<p>Uses <a href="https://code.google.com/p/leveldb/" target="_new"><i>LevelDB</i></a> for a simple key value pair database.</p>
+	<p>Use this node to <b>get</b>, or retrieve the data already saved in the database.</p>
+	<p><b>msg.topic</b> must hold the <i>key</i> for the database, and the result is returned in <b>msg.payload</b>.</p>
+</script>
+
+<script type="text/javascript">
+	RED.nodes.registerType('leveldb in',{
+		category: 'storage-input',
+		color:"#dbb84d",
+		defaults: {
+			level: {type:"leveldbase",required:true},
+			name: {value:""}
+		},
+		inputs:1,
+		outputs:1,
+		icon: "leveldb.png",
+		label: function() {
+			var levelNode = RED.nodes.node(this.level);
+			return this.name||(levelNode?levelNode.label():"leveldb");
+		},
+			labelStyle: function() {
+			return this.name?"node_label_italic":"";
+		}
+	});
+</script>
+
+
+<script type="text/x-red" data-template-name="leveldb out">
+	<div class="form-row node-input-level">
+		<label for="node-input-level"><i class="icon-briefcase"></i> Database</label>
+		<input type="text" id="node-input-level">
+	</div>
+	<div class="form-row">
+		<label for="node-input-name"><i class="icon-tag"></i> Name</label>
+		<input type="text" id="node-input-name" placeholder="Name">
+	</div>
+</script>
+
+
+<script type="text/x-red" data-help-name="leveldb out">
+	<p>Uses <a href="https://code.google.com/p/leveldb/" target="_new"><i>LevelDB</i></a> for a simple key value pair database.</p>
+	<p>Use this node to <b>put</b> (save) the <b>msg.payload</b> to the named database file, using <b>msg.topic</b> as the key.</p>
+	<p>To <b>delete</b> information do a <b>put</b> to the required <b>msg.topic</b> (key) with a <b>msg.payload</b> of <b><i>null</i></b>.</p>
+</script>
+
+<script type="text/javascript">
+	RED.nodes.registerType('leveldb out',{
+		category: 'storage-output',
+		color:"#dbb84d",
+		defaults: {
+			level: {type:"leveldbase",required:true},
+			op: {value:"put",required:true},
+			name: {value:""}
+		},
+		inputs:1,
+		outputs:0,
+		icon: "leveldb.png",
+		align: "right",
+		label: function() {
+			var levelNode = RED.nodes.node(this.level);
+			return this.name||(levelNode?levelNode.label():"leveldb");
+		},
+			labelStyle: function() {
+			return this.name?"node_label_italic":"";
+		}
+	});
+</script>

nodes/storage/67-leveldb.js

@@ -0,0 +1,90 @@
+/**
+ * Copyright 2013 IBM Corp.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ **/
+
+var RED = require("../../red/red");
+var lvldb = require('leveldb');
+
+function LevelNode(n) {
+	RED.nodes.createNode(this,n);
+	this.dbname = n.db;
+	lvldb.open(this.dbname, { create_if_missing: true }, onOpen);
+	var node = this;
+	function onOpen(err, db) {
+		if (err) node.error(err);
+		node.db = db;
+	}
+}
+RED.nodes.registerType("leveldbase",LevelNode);
+
+
+function LevelDBNodeIn(n) {
+	RED.nodes.createNode(this,n);
+	this.level = n.level;
+	this.op = n.op;
+	this.levelConfig = RED.nodes.getNode(this.level);
+
+	if (this.levelConfig) {
+		var node = this;
+		node.on("input", function(msg) {
+			if (typeof msg.topic === 'string') {
+				node.levelConfig.db.get(msg.topic, function(err, value) {
+					if (err) node.error(err);
+					msg.payload = JSON.parse(value);
+					delete msg.cmd;
+					node.send(msg);
+				});
+			}
+			else {
+				if (typeof msg.topic !== 'string') node.error("msg.topic (the key is not defined");
+			}
+		});
+	}
+	else {
+		this.error("LevelDB database name not configured");
+	}
+}
+RED.nodes.registerType("leveldb in",LevelDBNodeIn);
+
+
+function LevelDBNodeOut(n) {
+	RED.nodes.createNode(this,n);
+	this.level = n.level;
+	this.levelConfig = RED.nodes.getNode(this.level);
+
+	if (this.levelConfig) {
+		var node = this;
+		node.on("input", function(msg) {
+			if (typeof msg.topic === 'string') {
+				console.log(msg);
+				if (msg.payload === null) {
+					node.levelConfig.db.del(msg.topic);
+				}
+				else {
+					node.levelConfig.db.put(msg.topic, JSON.stringify(msg.payload), function(err) {
+						if (err) node.error(err);
+					});
+				}
+			}
+			else {
+				if (typeof msg.topic !== 'string') node.error("msg.topic (the key is not defined");
+			}
+		});
+	}
+	else {
+		this.error("LevelDB database name not configured");
+	}
+}
+RED.nodes.registerType("leveldb out",LevelDBNodeOut);