From d820f55358b29f408dc062da377baaf2bd63a9ee Mon Sep 17 00:00:00 2001
From: Dave Conway-Jones <conway@uk.ibm.com>
Date: Thu, 15 Jul 2021 22:15:46 +0100
Subject: [PATCH] Add push to front of rate limit queue.

(moved random delay to top to group with other delay types.
Tests and docs to follow
---
 .../@node-red/nodes/core/function/89-delay.js | 49 +++++++++++--------
 1 file changed, 28 insertions(+), 21 deletions(-)

diff --git a/packages/node_modules/@node-red/nodes/core/function/89-delay.js b/packages/node_modules/@node-red/nodes/core/function/89-delay.js
index 10f30796b..850497e22 100644
--- a/packages/node_modules/@node-red/nodes/core/function/89-delay.js
+++ b/packages/node_modules/@node-red/nodes/core/function/89-delay.js
@@ -154,6 +154,7 @@ module.exports = function(RED) {
         }, 15 * 1000);
         node.on("close", function() { clearInterval(loggerId); });
 
+        // The delay type modes
         if (node.pauseType === "delay") {
             node.on("input", function(msg, send, done) {
                 var id = ourTimeout(function() {
@@ -199,6 +200,29 @@ module.exports = function(RED) {
             });
             node.on("close", function() { clearDelayList(); });
         }
+        else if (node.pauseType === "random") {
+            node.on("input", function(msg, send, done) {
+                var wait = node.randomFirst + (node.diff * Math.random());
+                var id = ourTimeout(function() {
+                    node.idList.splice(node.idList.indexOf(id),1);
+                    send(msg);
+                    if (node.timeout >= 1000) {
+                        node.status({fill:"blue",shape:"dot",text:node.idList.length});
+                    }
+                    done();
+                }, wait, () => done());
+                if (Object.keys(msg).length === 2 && msg.hasOwnProperty("flush")) { id.clear(); }
+                else { node.idList.push(id); }
+                if (msg.hasOwnProperty("reset")) { clearDelayList(true); }
+                if (msg.hasOwnProperty("flush")) { flushDelayList(msg.flush); done(); }
+                if (node.timeout >= 1000) {
+                    node.status({fill:"blue",shape:"dot",text:node.idList.length});
+                }
+            });
+            node.on("close", function() { clearDelayList(); });
+        }
+
+        // The rate limit/queue type modes
         else if (node.pauseType === "rate") {
             node.on("input", function(msg, send, done) {
                 if (msg.hasOwnProperty("reset")) {
@@ -217,6 +241,7 @@ module.exports = function(RED) {
                 if (!node.drop) {
                     var m = RED.util.cloneMessage(msg);
                     delete m.flush;
+                    delete m.lifo;
                     if (Object.keys(m).length > 1) {
                         if (node.intervalID !== -1) {
                             if (node.allowrate && msg.hasOwnProperty("rate") && !isNaN(parseFloat(msg.rate)) && node.rate !== msg.rate) {
@@ -228,6 +253,9 @@ module.exports = function(RED) {
                             if ((max_msgs > 0) && (node.buffer.length >= max_msgs)) {
                                 node.buffer = [];
                                 node.error(RED._("delay.errors.too-many"), msg);
+                            } else if (msg.lifo) {
+                                node.buffer.unshift({msg: m, send: send, done: done});
+                                node.reportDepth();
                             } else {
                                 node.buffer.push({msg: m, send: send, done: done});
                                 node.reportDepth();
@@ -385,27 +413,6 @@ module.exports = function(RED) {
                 node.status({});
             });
         }
-        else if (node.pauseType === "random") {
-            node.on("input", function(msg, send, done) {
-                var wait = node.randomFirst + (node.diff * Math.random());
-                var id = ourTimeout(function() {
-                    node.idList.splice(node.idList.indexOf(id),1);
-                    send(msg);
-                    if (node.timeout >= 1000) {
-                        node.status({fill:"blue",shape:"dot",text:node.idList.length});
-                    }
-                    done();
-                }, wait, () => done());
-                if (Object.keys(msg).length === 2 && msg.hasOwnProperty("flush")) { id.clear(); }
-                else { node.idList.push(id); }
-                if (msg.hasOwnProperty("reset")) { clearDelayList(true); }
-                if (msg.hasOwnProperty("flush")) { flushDelayList(msg.flush); done(); }
-                if (node.timeout >= 1000) {
-                    node.status({fill:"blue",shape:"dot",text:node.idList.length});
-                }
-            });
-            node.on("close", function() { clearDelayList(); });
-        }
     }
     RED.nodes.registerType("delay",DelayNode);
 }