Implement idempotent command tracking with cleanup and caching for improved request handling

web/server/server.js

@@ -51,6 +51,29 @@ if (lastUpdate > 0) {
 let pendingCommands = [];
 let nextCommandId = 1;  // Monotonic ID for deduplication
 
+// ========== Idempotent Command Tracking ==========
+
+const processedCommands = new Map(); // commandId -> { result, timestamp }
+const COMMAND_TTL = 5 * 60 * 1000;   // 5 minutes
+
+// Periodic cleanup of expired entries
+setInterval(() => {
+  const cutoff = Date.now() - COMMAND_TTL;
+  for (const [id, entry] of processedCommands) {
+    if (entry.timestamp < cutoff) processedCommands.delete(id);
+  }
+}, 60_000);
+
+function checkIdempotent(commandId) {
+  if (!commandId) return null;
+  return processedCommands.get(commandId)?.result || null;
+}
+
+function recordCommand(commandId, result) {
+  if (!commandId) return;
+  processedCommands.set(commandId, { result, timestamp: Date.now() });
+}
+
 // ========== Helpers ==========
 
 function broadcastToClients(data) {
@@ -264,7 +287,11 @@ app.get('/api/recipes', (req, res) => {
 // Order an item from storage
 app.post('/api/order', (req, res) => {
   try {
-    const { itemName, amount, dropperName } = req.body;
+    const { itemName, amount, dropperName, commandId } = req.body;
+
+    const cached = checkIdempotent(commandId);
+    if (cached) return res.json(cached);
+
     if (!itemName || !amount) {
       return res.status(400).json({ error: 'Missing itemName or amount' });
     }
@@ -272,14 +299,17 @@ app.post('/api/order', (req, res) => {
     const command = {
       type: 'command',
       action: 'order',
+      commandId,
       itemName,
       amount: parseInt(amount),
       dropperName: dropperName || null,
     };
     
     pushCommandToBridge(command);
+    const result = { success: true, commandId, message: `Order sent: ${itemName} x${amount}` };
+    recordCommand(commandId, result);
     console.log(`📦 Order: ${itemName} x${amount}`);
-    res.json({ success: true, message: `Order sent: ${itemName} x${amount}` });
+    res.json(result);
   } catch (error) {
     res.status(500).json({ error: error.message });
   }
@@ -315,9 +345,16 @@ app.post('/api/dropper-nicknames', (req, res) => {
 // Request inventory scan
 app.post('/api/scan', (req, res) => {
   try {
-    pushCommandToBridge({ type: 'command', action: 'scan' });
+    const { commandId } = req.body || {};
+
+    const cached = checkIdempotent(commandId);
+    if (cached) return res.json(cached);
+
+    pushCommandToBridge({ type: 'command', action: 'scan', commandId });
+    const result = { success: true, commandId, message: 'Scan requested' };
+    recordCommand(commandId, result);
     console.log('🔍 Scan requested');
-    res.json({ success: true, message: 'Scan requested' });
+    res.json(result);
   } catch (error) {
     res.status(500).json({ error: error.message });
   }
@@ -326,9 +363,16 @@ app.post('/api/scan', (req, res) => {
 // Toggle smelting pause
 app.post('/api/smelting/toggle', (req, res) => {
   try {
-    pushCommandToBridge({ type: 'command', action: 'toggle_pause' });
+    const { commandId } = req.body || {};
+
+    const cached = checkIdempotent(commandId);
+    if (cached) return res.json(cached);
+
+    pushCommandToBridge({ type: 'command', action: 'toggle_pause', commandId });
+    const result = { success: true, commandId };
+    recordCommand(commandId, result);
     console.log('🔥 Smelting toggle requested');
-    res.json({ success: true });
+    res.json(result);
   } catch (error) {
     res.status(500).json({ error: error.message });
   }
@@ -337,12 +381,18 @@ app.post('/api/smelting/toggle', (req, res) => {
 // Toggle a specific recipe
 app.post('/api/recipes/toggle', (req, res) => {
   try {
-    const { recipe } = req.body;
+    const { recipe, commandId } = req.body;
+
+    const cached = checkIdempotent(commandId);
+    if (cached) return res.json(cached);
+
     if (!recipe) return res.status(400).json({ error: 'Missing recipe name' });
     
-    pushCommandToBridge({ type: 'command', action: 'toggle_recipe', recipe });
+    pushCommandToBridge({ type: 'command', action: 'toggle_recipe', commandId, recipe });
+    const result = { success: true, commandId };
+    recordCommand(commandId, result);
     console.log(`🔄 Recipe toggle: ${recipe}`);
-    res.json({ success: true });
+    res.json(result);
   } catch (error) {
     res.status(500).json({ error: error.message });
   }
@@ -350,24 +400,42 @@ app.post('/api/recipes/toggle', (req, res) => {
 
 // Enable/disable all recipes
 app.post('/api/recipes/enable-all', (req, res) => {
-  pushCommandToBridge({ type: 'command', action: 'enable_all' });
+  const { commandId } = req.body || {};
-  res.json({ success: true });
+  const cached = checkIdempotent(commandId);
+  if (cached) return res.json(cached);
+
+  pushCommandToBridge({ type: 'command', action: 'enable_all', commandId });
+  const result = { success: true, commandId };
+  recordCommand(commandId, result);
+  res.json(result);
 });
 
 app.post('/api/recipes/disable-all', (req, res) => {
-  pushCommandToBridge({ type: 'command', action: 'disable_all' });
+  const { commandId } = req.body || {};
-  res.json({ success: true });
+  const cached = checkIdempotent(commandId);
+  if (cached) return res.json(cached);
+
+  pushCommandToBridge({ type: 'command', action: 'disable_all', commandId });
+  const result = { success: true, commandId };
+  recordCommand(commandId, result);
+  res.json(result);
 });
 
 // Sort barrel
 app.post('/api/sort-barrel', (req, res) => {
   try {
-    const { barrelName } = req.body;
+    const { barrelName, commandId } = req.body;
+
+    const cached = checkIdempotent(commandId);
+    if (cached) return res.json(cached);
+
     if (!barrelName) return res.status(400).json({ error: 'Missing barrelName' });
     
-    pushCommandToBridge({ type: 'command', action: 'sort_barrel', barrelName });
+    pushCommandToBridge({ type: 'command', action: 'sort_barrel', commandId, barrelName });
+    const result = { success: true, commandId };
+    recordCommand(commandId, result);
     console.log(`📦 Sort barrel: ${barrelName}`);
-    res.json({ success: true });
+    res.json(result);
   } catch (error) {
     res.status(500).json({ error: error.message });
   }
@@ -376,12 +444,18 @@ app.post('/api/sort-barrel', (req, res) => {
 // Craft item
 app.post('/api/craft', (req, res) => {
   try {
-    const { recipeIdx } = req.body;
+    const { recipeIdx, commandId } = req.body;
+
+    const cached = checkIdempotent(commandId);
+    if (cached) return res.json(cached);
+
     if (recipeIdx === undefined) return res.status(400).json({ error: 'Missing recipeIdx' });
     
-    pushCommandToBridge({ type: 'command', action: 'craft', recipeIdx: parseInt(recipeIdx) });
+    pushCommandToBridge({ type: 'command', action: 'craft', commandId, recipeIdx: parseInt(recipeIdx) });
+    const result = { success: true, commandId };
+    recordCommand(commandId, result);
     console.log(`🔨 Craft request: recipe #${recipeIdx}`);
-    res.json({ success: true });
+    res.json(result);
   } catch (error) {
     res.status(500).json({ error: error.message });
   }
@@ -441,10 +515,11 @@ app.post('/api/bridge/commands/ack', (req, res) => {
 // Bridge sends command result
 app.post('/api/bridge/result', (req, res) => {
   try {
-    const { action, success, message, error: err } = req.body;
+    const { action, commandId, success, message, error: err } = req.body;
     
     broadcastToClients({
       type: 'command_result',
+      commandId,
       action,
       success,
       message,
@@ -617,9 +692,10 @@ wss.on('connection', (ws, req) => {
           // Full state update from bridge
           updateStateFromBridge(data);
         } else if (data.type === 'command_result') {
-          // Command result from bridge
+          // Command result from bridge — include commandId
           broadcastToClients({
             type: 'command_result',
+            commandId: data.commandId,
             action: data.action,
             success: data.success,
             message: data.message,
@@ -683,8 +759,17 @@ wss.on('connection', (ws, req) => {
       const data = JSON.parse(message);
       
       if (data.type === 'command') {
+        // Idempotency check for WS commands
+        const cached = checkIdempotent(data.commandId);
+        if (cached) {
+          ws.send(JSON.stringify({ type: 'command_result', commandId: data.commandId, ...cached }));
+          return;
+        }
         // Forward command to bridge
         pushCommandToBridge(data);
+        if (data.commandId) {
+          recordCommand(data.commandId, { success: true, commandId: data.commandId });
+        }
       }
     } catch (error) {
       console.error('❌ Error processing web client message:', error);