WIP: Start refactor of nodes/Flow.js

packages/node_modules/@node-red/runtime/lib/nodes/flows/index.js

@@ -141,8 +141,11 @@ function setFlows(_config,type,muteLog,forceStart) {
             return _config.rev;
         });
     } else {
+        // Clone the provided config so it can be manipulated
         config = clone(_config);
+        // Parse the configuration
         newFlowConfig = flowUtil.parseConfig(clone(config));
+        // Generate a diff to identify what has changed
         diff = flowUtil.diffConfigs(activeFlowConfig,newFlowConfig);
 
         // Now the flows have been compared, remove any credentials from newFlowConfig
@@ -153,8 +156,14 @@ function setFlows(_config,type,muteLog,forceStart) {
             }
         }
 
+        // Allow the credential store to remove anything no longer needed
         credentials.clean(config);
+
+        // Remember whether credentials need saving or not
         var credsDirty = credentials.dirty();
+
+        // Get the latest credentials and ask storage to save them (if needed)
+        // as well as the new flow configuration.
         configSavePromise = credentials.export().then(function(creds) {
             var saveConfig = {
                 flows: config,
@@ -176,15 +185,20 @@ function setFlows(_config,type,muteLog,forceStart) {
             };
             activeFlowConfig = newFlowConfig;
             if (forceStart || started) {
-                return stop(type,diff,muteLog).then(function() {
-                    return context.clean(activeFlowConfig).then(function() {
-                        start(type,diff,muteLog).then(function() {
-                            events.emit("runtime-event",{id:"runtime-deploy",payload:{revision:flowRevision},retain: true});
-                        });
-                        return flowRevision;
+                // Flows are running (or should be)
+
+                // Stop the active flows (according to deploy type and the diff)
+                return stop(type,diff,muteLog).then(() => {
+                    // Once stopped, allow context to remove anything no longer needed
+                    return context.clean(activeFlowConfig)
+                }).then(() => {
+                    // Start the active flows
+                    start(type,diff,muteLog).then(() => {
+                        events.emit("runtime-event",{id:"runtime-deploy",payload:{revision:flowRevision},retain: true});
                     });
-                }).catch(function(err) {
-                })
+                    // Return the new revision asynchronously to the actual start
+                    return flowRevision;
+                }).catch(function(err) { })
             } else {
                 events.emit("runtime-event",{id:"runtime-deploy",payload:{revision:flowRevision},retain: true});
             }
@@ -273,10 +287,10 @@ function handleStatus(node,statusMessage) {
 
 
 function start(type,diff,muteLog) {
-    //dumpActiveNodes();
     type = type||"full";
     started = true;
     var i;
+    // If there are missing types, report them, emit the necessary runtime event and return
     if (activeFlowConfig.missingTypes.length > 0) {
         log.info(log._("nodes.flows.missing-types"));
         var knownUnknowns = 0;
@@ -297,8 +311,10 @@ function start(type,diff,muteLog) {
             log.info("  "+settings.userDir);
         }
         events.emit("runtime-event",{id:"runtime-state",payload:{error:"missing-types", type:"warning",text:"notification.warnings.missing-types",types:activeFlowConfig.missingTypes},retain:true});
-        return when.resolve();
+        return Promise.resolve();
     }
+
+    // In safe mode, don't actually start anything, emit the necessary runtime event and return
     if (settings.safeMode) {
         log.info("*****************************************************************")
         log.info(log._("nodes.flows.safe-mode"));
@@ -306,6 +322,7 @@ function start(type,diff,muteLog) {
         events.emit("runtime-event",{id:"runtime-state",payload:{error:"safe-mode", type:"warning",text:"notification.warnings.safe-mode"},retain:true});
         return Promise.resolve();
     }
+
     if (!muteLog) {
         if (type !== "full") {
             log.info(log._("nodes.flows.starting-modified-"+type));
@@ -313,15 +330,22 @@ function start(type,diff,muteLog) {
             log.info(log._("nodes.flows.starting-flows"));
         }
     }
+
     var id;
     if (type === "full") {
+        // A full start means everything should
+
+        // Check the 'global' flow is running
         if (!activeFlows['global']) {
             log.debug("red/nodes/flows.start : starting flow : global");
             activeFlows['global'] = Flow.create(activeFlowConfig);
         }
+
+        // Check each flow in the active configuration
         for (id in activeFlowConfig.flows) {
             if (activeFlowConfig.flows.hasOwnProperty(id)) {
                 if (!activeFlowConfig.flows[id].disabled && !activeFlows[id]) {
+                    // This flow is not disabled, nor is it currently active, so create it
                     activeFlows[id] = Flow.create(activeFlowConfig,activeFlowConfig.flows[id]);
                     log.debug("red/nodes/flows.start : starting flow : "+id);
                 } else {
@@ -330,13 +354,18 @@ function start(type,diff,muteLog) {
             }
         }
     } else {
+        // A modified-type deploy means restarting things that have changed
+
+        // Update the global flow
         activeFlows['global'].update(activeFlowConfig,activeFlowConfig);
         for (id in activeFlowConfig.flows) {
             if (activeFlowConfig.flows.hasOwnProperty(id)) {
                 if (!activeFlowConfig.flows[id].disabled) {
                     if (activeFlows[id]) {
+                        // This flow exists and is not disabled, so update it
                         activeFlows[id].update(activeFlowConfig,activeFlowConfig.flows[id]);
                     } else {
+                        // This flow didn't previously exist, so create it
                         activeFlows[id] = Flow.create(activeFlowConfig,activeFlowConfig.flows[id]);
                         log.debug("red/nodes/flows.start : starting flow : "+id);
                     }
@@ -347,9 +376,12 @@ function start(type,diff,muteLog) {
         }
     }
 
+    // Having created or updated all flows, now start them.
     for (id in activeFlows) {
         if (activeFlows.hasOwnProperty(id)) {
             activeFlows[id].start(diff);
+
+            // Create a map of node id to flow id and also a subflowInstance lookup map
             var activeNodes = activeFlows[id].getActiveNodes();
             Object.keys(activeNodes).forEach(function(nid) {
                 activeNodesToFlow[nid] = id;
@@ -376,7 +408,7 @@ function start(type,diff,muteLog) {
             log.info(log._("nodes.flows.started-flows"));
         }
     }
-    return when.resolve();
+    return Promise.resolve();
 }
 
 function stop(type,diff,muteLog) {