From 885c6ad98edec7fe999a05fdc70cd1892ebc8a93 Mon Sep 17 00:00:00 2001
From: KieranDolan <dolankie@uk.ibm.com>
Date: Wed, 8 Feb 2017 18:45:13 +0000
Subject: [PATCH] Added output message flow after insert or update

Configurable output flow for success, failure or all scenarios.
When successful output message has updated rev and new id (for insert)
On failure, original message is forwarded with dbError field
---
 77-cloudant-cf.html | 26 ++++++++++++++++++++++++--
 77-cloudant-cf.js   | 34 +++++++++++++++++++++++++++++++++-
 README.md           |  5 +++++
 3 files changed, 62 insertions(+), 3 deletions(-)

diff --git a/77-cloudant-cf.html b/77-cloudant-cf.html
index ae0c58d..5ac85f7 100644
--- a/77-cloudant-cf.html
+++ b/77-cloudant-cf.html
@@ -85,6 +85,14 @@
         <label for="node-input-name"><i class="fa fa-tag"></i> Name</label>
         <input type="text" id="node-input-name" placeholder="Name" style="width:65%;">
     </div>
+    <div class="form-row">
+        <label for="node-input-outputmsg"><i class="fa fa-wrench"></i>output msg</label>
+        <select type="text" id="node-input-outputmsg" style="width:68%;">
+            <option value="none">none</option>
+            <option value="error">error</option>
+            <option value="success">success</option>
+            <option value="all">all</option>
+        </select>
     <script>
         $("#node-input-operation").change(function() {
             var id = $("#node-input-operation option:selected").val();
@@ -140,7 +148,8 @@
             database: { value:"", required:true, validate:validateDatabase },
             service: { value:"", required:true },
             payonly: { value:false },
-            operation: { value:"insert" }
+            operation: { value:"insert" },
+            outputmsg: { value:"none" }
         },
         inputs: 1,
         outputs: 0,
@@ -150,7 +159,12 @@
         labelStyle: function() {
             return this.name?"node_label_italic":"";
         },
-        oneditprepare: oneditprepare
+        oneditprepare: oneditprepare,
+        oneditsave: function() {
+            var oval = $("#node-input-outputmsg").val();
+            if (oval == "none") this.outputs = 0;
+            else this.outputs = 1;
+        }
     });
 
     RED.nodes.registerType("cloudant in", {
@@ -272,6 +286,14 @@
             <li>The first character can't be <code>_</code></li>
         </ul>
     </p>
+    <p>
+        You can specify that an output message is generated - either always (all) or for success or error. 
+        In the event of an error the message output will be the original 
+        message with a dbError field showing the error. For successful inserts or updates, 
+        the message output will be the original message with the _id and _rev fields 
+        updated in either the message body or in the payload.
+        The default setting is that no output message is generated.
+    </p>
     <p>
         Your document should avoid having top-level fields that start with
         <code>_</code>, with exceptions for <code>_id</code>, <code>_rev</code>
diff --git a/77-cloudant-cf.js b/77-cloudant-cf.js
index da9e816..58a3af4 100644
--- a/77-cloudant-cf.js
+++ b/77-cloudant-cf.js
@@ -80,6 +80,7 @@ module.exports = function(RED) {
 
         this.operation      = n.operation;
         this.payonly        = n.payonly || false;
+        this.outputMsg      = n.outputmsg || "none";
         this.database       = _cleanDatabaseName(n.database, this);
         this.cloudantConfig = _getCloudantConfig(n);
 
@@ -103,7 +104,6 @@ module.exports = function(RED) {
                     return node.error(err.description, err); 
                 }
 
-                delete msg._msgid;
                 handleMessage(cloudant, node, msg);
             });
         });
@@ -134,7 +134,10 @@ module.exports = function(RED) {
         }
 
         function handleMessage(cloudant, node, msg) {
+            var origMsgId = msg._msgid ;
+            delete msg._msgid;
             if (node.operation === "insert") {
+                var origMsg = msg ;
                 var msg  = node.payonly ? msg.payload : msg;
                 var root = node.payonly ? "payload" : "msg";
                 var doc  = parseMessage(msg, root);
@@ -144,6 +147,35 @@ module.exports = function(RED) {
                         console.trace();
                         console.log(node.error.toString());
                         node.error("Failed to insert document: " + err.description, msg);
+                        if (node.outputMsg && (node.outputMsg == "error" 
+                        || node.outputMsg == "all")) {
+                            //send original message on error 
+                            origMsg._msgid = origMsgId ;
+                            origMsg.dbError = {} ;
+
+                            origMsg.dbError.statusCode = err.statusCode;
+                            origMsg.dbError.description = err.description;
+                            origMsg.dbError.message = err.message;
+                            origMsg.dbError.reason = err.reason;
+                            origMsg.dbError.scope = err.scope;
+                            node.send([origMsg]);
+                        }
+                    }
+                    else if (node.outputMsg && (node.outputMsg == "success"
+                    || node.outputMsg == "all")) {
+                        // send message with updated id and rev on success
+                        origMsg._msgid = origMsgId ;
+                        delete origMsg.dbError;  // just in case original message came from error path                      
+                        if (node.payonly) {
+                            origMsg.payload._id = body.id;
+                            origMsg.payload._rev = body.rev;
+                        }
+                        else {
+                            origMsg._id = body.id;
+                            origMsg._rev = body.rev;
+                        }
+
+                        node.send([origMsg]);
                     }
                 });
             }
diff --git a/README.md b/README.md
index 790b9fb..5a5edb9 100644
--- a/README.md
+++ b/README.md
@@ -23,6 +23,11 @@ in JSON format, it will be transformed before being stored.
 For **update** and **delete**, you must pass the `_id` and the `_rev`as part
 of the input `msg` object.
 
+For **insert** and **update**, you can specify that an output message is generated - either
+always (all) or for success or error. In the event of an error the message output will be the original
+message with a dbError field showing the error. For successful inserts or updates, the message output
+will be the original message with the _id and _rev fields updated in either the message body or in the payload.
+
 To **search** for a document you have two options: get a document directly by
 its `_id` or use an existing [search index](https://cloudant.com/for-developers/search/)
 from the database. For both cases, the query should be passed in the