Let sqlite open RO as well as RW

Also better reuse of connection object

storage/sqlite/package.json

@@ -1,6 +1,6 @@
 {
     "name": "node-red-node-sqlite",
-    "version": "0.3.0",
+    "version": "0.3.2",
     "description": "A sqlite node for Node-RED",
     "dependencies": {
         "sqlite3": "^4.0.2"

storage/sqlite/sqlite.html

@@ -4,13 +4,24 @@
         <label for="node-config-input-db"><i class="fa fa-database"></i> Database</label>
         <input type="text" id="node-config-input-db" placeholder="/tmp/sqlite">
     </div>
+    <div class="form-row">
+        <label for="node-config-input-mode">Mode</label>
+        <select id="node-config-input-mode" style="width:70%">
+            <option value="RWC">Read-Write-Create</option>
+            <option value="RW">Read-Write</option>
+            <option value="RO">Read-Only</option>
+        </select>
+    </div>
+    <div class="form-tips"><b>Note</b>: Setting the database name to <code>:memory:</code>
+    will create a non-persistant in memory database.</div>
 </script>
 
 <script type="text/javascript">
     RED.nodes.registerType('sqlitedb',{
         category: 'config',
         defaults: {
-            db: {value:"",required:true}
+            db: {value:"", required:true},
+            mode: {value:"RWC"}
         },
         label: function() {
             return this.db;

storage/sqlite/sqlite.js

@@ -7,10 +7,14 @@ module.exports = function(RED) {
         RED.nodes.createNode(this,n);
 
         this.dbname = n.db;
+        this.mod = n.mode;
+        if (n.mode === "RWC") { this.mode = sqlite3.OPEN_READWRITE | sqlite3.OPEN_CREATE; }
+        if (n.mode === "RW") { this.mode = sqlite3.OPEN_READWRITE; }
+        if (n.mode === "RO") { this.mode = sqlite3.OPEN_READONLY; }
         var node = this;
 
         node.doConnect = function() {
-            node.db = new sqlite3.Database(node.dbname);
+            node.db = node.db || new sqlite3.Database(node.dbname,node.mode);
             node.db.on('open', function() {
                 if (node.tick) { clearTimeout(node.tick); }
                 node.log("opened "+node.dbname+" ok");
@@ -41,6 +45,7 @@ module.exports = function(RED) {
 
         if (this.mydbConfig) {
             this.mydbConfig.doConnect();
+            node.status({fill:"green",shape:"dot",text:this.mydbConfig.mod});
             var bind = [];
             node.on("input", function(msg) {
                 if (this.sqlquery == "msg.topic"){