Add demo mode for Railway deployment without Docker

- Remove Docker installation from Dockerfile to avoid memory issues
- Add graceful fallback when Docker daemon not available
- Server runs in 'demo mode' showing frontend but disabling scenarios
- Users can still explore the interface and see scenario descriptions
- This allows Railway deployment to succeed even without Docker support

Ready for Railway deployment - will work with or without Docker\!

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: alanops

Dockerfile

@@ -1,22 +1,11 @@
-# Simplified build for Railway - no Docker build during image creation
-FROM node:18-slim
-
-# Install only essential packages
-RUN apt-get update && apt-get install -y \
-    curl \
-    && rm -rf /var/lib/apt/lists/*
-
-# Install Docker CLI (smaller alternative)
-RUN curl -fsSL https://get.docker.com | sh
+# Ultra-minimal build for Railway
+FROM node:18-alpine
 
 WORKDIR /app
 
-# Copy package files and install dependencies
+# Copy package files and install dependencies (frontend)
 COPY package*.json ./
-RUN npm ci --only=production
-
-COPY backend/package*.json ./backend/
-RUN cd backend && npm ci --only=production
+RUN npm ci --omit=dev --no-audit --no-fund
 
 # Copy and build frontend
 COPY src/ ./src/
@@ -28,11 +17,15 @@ COPY tsconfig.json ./
 
 RUN npm run build
 
+# Copy backend package files and install
+COPY backend/package*.json ./backend/
+RUN cd backend && npm ci --omit=dev --no-audit --no-fund
+
 # Copy and build backend
 COPY backend/ ./backend/
 RUN cd backend && npm run build
 
-# Copy scenario definitions (build images at runtime, not build time)
+# Copy scenario definitions (no Docker installation - will use Railway's Docker)
 COPY scenarios/ ./scenarios/
 COPY docker/ ./docker/
 COPY Makefile ./
@@ -45,5 +38,5 @@ WORKDIR /app/backend
 # Expose port
 EXPOSE $PORT
 
-# Start backend server (builds scenario images on first use)
+# Start backend server (scenarios will build at runtime using Railway's Docker)
 CMD ["node", "dist/index.js"]

backend/index.ts

@@ -93,6 +93,16 @@ async function checkDockerImage(imageName: string): Promise<boolean> {
 }
 
 async function startScenarioContainer(socket: any, scenarioId: string) {
+  // Check if Docker is available
+  const dockerAvailable = await checkDockerDaemon()
+  if (!dockerAvailable) {
+    socket.emit('output', '\r\nDocker scenarios are not available in this deployment.\r\n')
+    socket.emit('output', 'This is a demo version - Docker scenarios require a Docker-enabled host.\r\n')
+    socket.emit('output', '\r\nYou can still explore the frontend interface!\r\n')
+    socket.emit('scenario-ready')
+    return
+  }
+
   // Map scenario IDs to Docker images
   const scenarioImages: Record<string, string> = {
     'k8s-crashloop': 'devopslearn/scenario-keycloak-crashloop',
@@ -261,28 +271,30 @@ async function buildScenarioImages() {
   }
 }
 
-// Initialize server with Docker checks
+// Initialize server with optional Docker checks
 async function initializeServer() {
-  console.log('Checking Docker daemon...')
+  console.log('Starting DevOps Dojo server...')
+  
   const dockerAvailable = await checkDockerDaemon()
 
-  if (!dockerAvailable) {
-    console.error('Error: Docker daemon is not accessible')
-    console.error('Please ensure Docker is installed and running')
-    process.exit(1)
+  if (dockerAvailable) {
+    console.log('Docker daemon is accessible - scenario support enabled')
+    await ensureDockerNetwork()
+    
+    // Build scenario images in background
+    buildScenarioImages().catch(error => {
+      console.log('Background scenario build failed:', error.message)
+    })
+  } else {
+    console.log('Docker daemon not available - running in demo mode (no scenarios)')
+    console.log('Frontend will work, but Docker scenarios will be unavailable')
   }
 
-  console.log('Docker daemon is accessible')
-  
-  await ensureDockerNetwork()
-  
-  // Build scenario images in background
-  buildScenarioImages().catch(error => {
-    console.log('Background scenario build failed:', error.message)
-  })
-  
   server.listen(PORT, () => {
     console.log(`DevOps Dojo server running on port ${PORT}`)
+    if (!dockerAvailable) {
+      console.log('Note: Running in demo mode - Docker scenarios disabled')
+    }
   })
 }
 

src/server/index.ts

@@ -93,6 +93,16 @@ async function checkDockerImage(imageName: string): Promise<boolean> {
 }
 
 async function startScenarioContainer(socket: any, scenarioId: string) {
+  // Check if Docker is available
+  const dockerAvailable = await checkDockerDaemon()
+  if (!dockerAvailable) {
+    socket.emit('output', '\r\nDocker scenarios are not available in this deployment.\r\n')
+    socket.emit('output', 'This is a demo version - Docker scenarios require a Docker-enabled host.\r\n')
+    socket.emit('output', '\r\nYou can still explore the frontend interface!\r\n')
+    socket.emit('scenario-ready')
+    return
+  }
+
   // Map scenario IDs to Docker images
   const scenarioImages: Record<string, string> = {
     'k8s-crashloop': 'devopslearn/scenario-keycloak-crashloop',
@@ -261,28 +271,30 @@ async function buildScenarioImages() {
   }
 }
 
-// Initialize server with Docker checks
+// Initialize server with optional Docker checks
 async function initializeServer() {
-  console.log('Checking Docker daemon...')
+  console.log('Starting DevOps Dojo server...')
+  
   const dockerAvailable = await checkDockerDaemon()
 
-  if (!dockerAvailable) {
-    console.error('Error: Docker daemon is not accessible')
-    console.error('Please ensure Docker is installed and running')
-    process.exit(1)
+  if (dockerAvailable) {
+    console.log('Docker daemon is accessible - scenario support enabled')
+    await ensureDockerNetwork()
+    
+    // Build scenario images in background
+    buildScenarioImages().catch(error => {
+      console.log('Background scenario build failed:', error.message)
+    })
+  } else {
+    console.log('Docker daemon not available - running in demo mode (no scenarios)')
+    console.log('Frontend will work, but Docker scenarios will be unavailable')
   }
 
-  console.log('Docker daemon is accessible')
-  
-  await ensureDockerNetwork()
-  
-  // Build scenario images in background
-  buildScenarioImages().catch(error => {
-    console.log('Background scenario build failed:', error.message)
-  })
-  
   server.listen(PORT, () => {
     console.log(`DevOps Dojo server running on port ${PORT}`)
+    if (!dockerAvailable) {
+      console.log('Note: Running in demo mode - Docker scenarios disabled')
+    }
   })
 }