Add delete option to File node

to replace msg.delete option - now deprecated but not removed.
Addresses some of the confusion  for Issue #399

nodes/core/storage/50-file.html

@@ -20,14 +20,17 @@
          <input type="text" id="node-input-filename" placeholder="Filename">
     </div>
     <div class="form-row">
+        <label for="node-input-overwriteFile"><i class="fa fa-random"></i> Action</label>
+        <select type="text" id="node-input-overwriteFile" style="display: inline-block; width: 250px; vertical-align: top;">
+            <option value="false">append to file</option>
+            <option value="true">overwrite file</option>
+            <option value="delete">delete file</option>
+        </select>
+    </div>
+    <div class="form-row" id="node-appline">
         <label>&nbsp;</label>
         <input type="checkbox" id="node-input-appendNewline" placeholder="Name" style="display: inline-block; width: auto; vertical-align: top;">
-        <label for="node-input-appendNewline" style="width: 70%;">Append newline ?</label>
+        <label for="node-input-appendNewline" style="width: 70%;">Add newline (\n) to each payload ?</label>
-    </div>
-    <div class="form-row">
-        <label>&nbsp;</label>
-        <input type="checkbox" id="node-input-overwriteFile" placeholder="Name" style="display: inline-block; width: auto; vertical-align: top;">
-        <label for="node-input-overwriteFile" style="width: 70%;">Overwrite complete file ?</label>
     </div>
     <div class="form-row">
         <label for="node-input-name"><i class="fa fa-tag"></i> Name</label>
@@ -40,7 +43,7 @@
     <p>The filename can be configured in the node, if left blank it should be set in an incoming message on <b>msg.filename</b>.</p>
     <p>A newline is added to every message. But this can be turned off if required, for example, to allow binary files to be written.</p>
     <p>The default behaviour is to append to the file. This can be changed to overwrite the file each time, for example if you want to output a "static" web page or report.</p>
-    <p>If a <b>msg.delete</b> property exists then the file will be deleted instead.</p>
+    <p>This node can also be configured to delete a file if required. <i>Note:</i> Using msg.delete is now deprecated.</p>
 </script>
 
 <script type="text/x-red" data-template-name="file in">
@@ -73,7 +76,7 @@
             name: {value:""},
             filename: {value:""},
             appendNewline: {value:true},
-            overwriteFile: {value:false}
+            overwriteFile: {value:"false"}
         },
         color:"BurlyWood",
         inputs:1,
@@ -81,10 +84,17 @@
         icon: "file.png",
         align: "right",
         label: function() {
-            return this.name||this.filename;
+            if (this.overwriteFile === "delete") { return this.name||"delete "+this.filename; }
+            else { return this.name||this.filename; }
         },
         labelStyle: function() {
             return this.name?"node_label_italic":"";
+        },
+        oneditprepare: function() {
+          $("#node-input-overwriteFile").on("change",function() {
+            if (this.value === "delete") { $("#node-appline").hide(); }
+            else { $("#node-appline").show(); }
+          });
         }
     });
 

nodes/core/storage/50-file.js

@@ -22,7 +22,7 @@ module.exports = function(RED) {
         RED.nodes.createNode(this,n);
         this.filename = n.filename || "";
         this.appendNewline = n.appendNewline;
-        this.overwriteFile = n.overwriteFile;
+        this.overwriteFile = n.overwriteFile.toString();
         var node = this;
         this.on("input",function(msg) {
             var filename;
@@ -37,31 +37,37 @@ module.exports = function(RED) {
             if (filename === "") {
                 node.warn('No filename specified');
             } else if (msg.hasOwnProperty('delete')) {
+                node.warn("Deprecated: please use specific delete option in config dialog.");
                 fs.unlink(filename, function (err) {
                     if (err) { node.warn('Failed to delete file : '+err); }
-                    //console.log('Deleted file",filename);
                 });
             } else if (typeof msg.payload != "undefined") {
                 var data = msg.payload;
-                if (typeof data === "object") {
+                if ((typeof data === "object")&&(!Buffer.isBuffer(data))) {
-                    if (!Buffer.isBuffer(data)) {
                     data = JSON.stringify(data);
                 }
-                }
                 if (typeof data === "boolean") { data = data.toString(); }
                 if ((this.appendNewline)&&(!Buffer.isBuffer(data))) { data += "\n"; }
-                if (this.overwriteFile) {
+                if (this.overwriteFile === "true") {
                     // using "binary" not {encoding:"binary"} to be 0.8 compatible for a while
+                    //fs.writeFile(filename, data, {encoding:"binary"}, function (err) {
                     fs.writeFile(filename, data, "binary", function (err) {
                         if (err) { node.warn('Failed to write to file : '+err); }
-                        //console.log('Message written to file',filename);
+                        else if (RED.settings.verbose) { node.log('wrote to file: '+filename); }
+                    });
+                }
+                else if (this.overwriteFile === "delete") {
+                    fs.unlink(filename, function (err) {
+                        if (err) { node.warn('Failed to delete file : '+err); }
+                        else if (RED.settings.verbose) { node.log("deleted file: "+filename); }
                     });
                 }
                 else {
-                    // using "binary" not {encoding:"binary"} to be 0.8 compatible for a while
+                    // using "binary" not {encoding:"binary"} to be 0.8 compatible for a while longer
+                    //fs.appendFile(filename, data, {encoding:"binary"}, function (err) {
                     fs.appendFile(filename, data, "binary", function (err) {
                         if (err) { node.warn('Failed to append to file : '+err); }
-                        //console.log('Message appended to file',filename);
+                        else if (RED.settings.verbose) { node.log('appended to file: '+filename); }
                     });
                 }
             }
@@ -69,6 +75,7 @@ module.exports = function(RED) {
     }
     RED.nodes.registerType("file",FileNode);
 
+
     function FileInNode(n) {
         RED.nodes.createNode(this,n);
 
@@ -108,4 +115,4 @@ module.exports = function(RED) {
         });
     }
     RED.nodes.registerType("file in",FileInNode);
-};
+}