Websockets Roadmap
42 sections • 572 topics
- 1. Understanding Protocol Basics
- 2. Understanding Handshake Process
- Example: Raw Handshake
- 3. Understanding Frame Structure
- 4. Understanding Connection States
- 5. Comparing WebSocket vs HTTP
- 6. Comparing WebSocket vs SSE
- 7. Comparing WebSocket vs Long Polling
- 8. Understanding Use Cases
- 9. Understanding Protocol Limitations
- 10. Understanding Browser Support
- 1. Building Basic URL
- Example: Basic ws URL
- 2. Building Secure URL
- Example: TLS WebSocket
- 3. Adding Query Parameters
- Example: URL builder
- 4. Encoding URL Components
- 5. Using Dynamic Hosts
- Example: Same-host WS
- 6. Handling Port Numbers
- 7. Using Path Parameters
- Example: REST-style path
- 8. Implementing URL Patterns
- 9. Validating URL Format
- Example: Validation
- 10. Handling Relative URLs
- 1. Creating Client Connection
- Example: Basic connect
- 2. Creating Secure Connection
- 3. Specifying Subprotocols
- Example: Subprotocol negotiation
- 4. Setting Connection URL
- 5. Checking Connection State
- Example: State check
- 6. Setting Binary Type
- Example: ArrayBuffer mode
- 7. Using WebSocket Properties
- 8. Feature Detection
- Example: Detect support
- 9. Handling Browser Compatibility
- 10. Using WebSocket in Workers
- Example: WS inside Web Worker
- 1. Setting Event Handlers
- Example: Assign handlers
- 2. Using addEventListener
- Example: Multiple listeners
- 3. Handling Connection Open
- Example: Initial sync on open
- 4. Handling Message Events
- 5. Handling Connection Close
- 6. Handling Connection Errors
- 7. Handling Page Unload
- Example: Clean shutdown
- 8. Understanding Event Order
- 9. Removing Event Listeners
- Example: AbortController
- 10. Debugging with DevTools
- 1. Handling Connection Open
- 2. Handling Connection Close
- Example: Close inspection
- 3. Understanding Close Codes
- 4. Sending Close Frame
- Example: Close with code/reason
- 5. Handling Abnormal Closure
- 6. Implementing Graceful Shutdown
- Graceful Shutdown Sequence
- 7. Cleaning Up Resources
- 8. Tracking Connection Duration
- Example: Uptime tracking
- 9. Implementing Connection Pooling
- 10. Handling Server Shutdown
- 1. Sending Text Messages
- Example: Text send
- 2. Sending JSON Data
- Example: Typed message envelope
- 3. Checking Buffer Amount
- Example: Backpressure-aware send
- 4. Queuing Messages
- Example: Pre-open queue
- 5. Validating Message Size
- 6. Handling Send Errors
- Example: Guarded send
- 7. Sending Binary Data
- Example: Send ArrayBuffer
- 8. Sending Typed Arrays
- 9. Implementing Message Batching
- Example: Time-window batcher
- 10. Compressing Messages
- 1. Handling Message Events
- Example: Router by type
- 2. Parsing Text Messages
- 3. Parsing JSON Messages
- Example: Safe parse
- 4. Validating Message Format
- Example: Zod schema
- 5. Handling Message Order
- 6. Handling Binary Messages
- Example: Branch on type
- 7. Reading Blob Data
- Example: Blob → ArrayBuffer
- 8. Processing Typed Arrays
- Example: Decode header + payload
- 9. Implementing Message Queue
- Example: Async iterator queue
- 10. Handling Large Messages
- 1. Designing Message Structure
- 2. Using JSON Format
- Example: JSON envelope
- 3. Using MessagePack
- Example: MessagePack
- 4. Using Protocol Buffers
- Example: protobuf.js
- 5. Using CBOR
- 6. Implementing Custom Binary Format
- Example: Fixed-layout header
- 7. Adding Message Versioning
- 8. Including Message Metadata
- 9. Implementing Message Acknowledgment
- Example: Ack flow
- 10. Validating Message Schema
- 1. Understanding Binary Data Types
- 2. Setting Binary Type
- 3. Creating ArrayBuffer
- Example: Create + fill
- 4. Using Typed Arrays
- 5. Using DataView
- Example: Endian control
- 6. Sending Binary Data
- 7. Receiving Binary Data
- Example: Decode incoming
- 8. Converting Blob to ArrayBuffer
- 9. Implementing Binary Protocol
- Example: TLV (type-length-value)
- 10. Handling Large Binary Files
- 1. Handling Connection Errors
- 2. Handling Network Errors
- Example: Online/offline awareness
- 3. Handling Protocol Errors
- 4. Handling Handshake Failures
- 5. Handling Message Parse Errors
- Example: Parse-error boundary
- 6. Creating Custom Error Types
- Example: Typed errors
- 7. Implementing Error Logging
- 8. Implementing Error Recovery
- Recovery Flow
- 9. Handling Buffer Overflow
- 10. Displaying User-Friendly Errors
- 1. Implementing Automatic Reconnection
- Example: Auto-reconnect skeleton
- 2. Using Exponential Backoff
- Example: Backoff function
- 3. Setting Maximum Retry Attempts
- 4. Implementing Jitter
- Example: Full jitter
- 5. Handling Network Status
- 6. Preserving Connection State
- 7. Implementing Circuit Breaker Pattern
- Example: Trip on threshold
- 8. Detecting Connection Health
- 9. Handling Manual Reconnection
- Example: User-triggered reconnect
- 10. Testing Reconnection Logic
- 1. Understanding Ping/Pong Mechanism
- 2. Sending Ping Frames
- Example: Node ws server ping
- 3. Handling Pong Responses
- Example: Mark alive on pong
- 4. Implementing Heartbeat
- Example: App-level heartbeat (browser)
- 5. Detecting Stale Connections
- 6. Closing Dead Connections
- Example: Forced terminate
- 7. Customizing Ping Interval
- 8. Handling Client Ping
- 9. Monitoring Connection Health
- 10. Implementing Custom Heartbeat Protocol
- Example: Ping with RTT
- 1. Validating Message Format
- 2. Using Validation Libraries
- 3. Sanitizing Input Data
- 4. Validating Message Types
- Example: Discriminated union
- 5. Checking Required Fields
- 6. Validating Data Types
- 7. Enforcing Length Limits
- 8. Validating Ranges
- Example: Numeric range
- 9. Using Custom Validators
- Example: Refine
- 10. Handling Validation Errors
- 1. Understanding Backpressure
- 2. Monitoring bufferedAmount Property
- Example: Drain detection
- 3. Implementing Flow Control
- 4. Using High Water Mark
- Example: HWM gating
- 5. Dropping Messages
- 6. Implementing Message Prioritization
- Example: Priority lanes
- 7. Handling Slow Clients
- 8. Implementing Client-Side Buffering
- 9. Detecting Backpressure Conditions
- 10. Testing Backpressure Scenarios
- 1. Installing ws Library
- Example: Install
- 2. Creating WebSocket Server
- Example: Minimal server
- 3. Handling Server Events
- 4. Accessing Client Connections
- Example: Iterate clients
- 5. Handling Client Events
- 6. Accessing Request Info
- Example: Read headers
- 7. Implementing HTTP Server Integration
- Example: Share port with Express
- 8. Handling Multiple Servers
- Example: Path-based routing
- 9. Gracefully Shutting Down Server
- 10. Broadcasting Messages
- Example: Broadcast helper
- 1. Setting Server Options
- 2. Configuring Connection Limits
- Example: Reject over limit
- 3. Setting Timeout Options
- 4. Enabling Compression
- Example: permessage-deflate
- 5. Configuring Compression Options
- 6. Setting Client Tracking
- 7. Configuring Verify Client
- Example: Async accept
- 8. Handling Upgrade Request
- Example: Manual upgrade
- 9. Setting No Server Mode
- 10. Configuring Environment Variables
- 1. Understanding Subprotocols
- 2. Negotiating Subprotocol
- Example: Server selector
- 3. Specifying Client Subprotocols
- Example: Multiple candidates
- 4. Selecting Server Subprotocol
- 5. Accessing Active Subprotocol
- Example: Branch on protocol
- 6. Implementing Custom Protocol
- 7. Using Standard Subprotocols
- 8. Handling Protocol Mismatch
- Example: Reject on mismatch
- 9. Versioning Subprotocols
- 10. Documenting Protocol Specification
- 1. Understanding WebSocket Extensions
- 2. Negotiating Extensions
- 3. Enabling Compression
- Example: Browser-default
- 4. Configuring Compression Parameters
- 5. Checking Active Extensions
- Example: Inspect
- 6. Disabling Extensions
- Example: Disable on server
- 7. Understanding Extension Overhead
- 8. Testing Extension Support
- 9. Implementing Per-Message Compression
- Example: Disable for one send
- 10. Handling Extension Negotiation
- 1. Understanding Request-Response over WebSocket
- 2. Generating Unique Message IDs
- 3. Tracking Pending Requests
- Example: Promise-based RPC
- 4. Implementing Timeout Handling
- 5. Matching Responses to Requests
- 6. Handling Request Errors
- 7. Implementing Callbacks
- Example: Callback variant
- 8. Using Promises for Requests
- 9. Canceling Pending Requests
- Example: AbortSignal integration
- 10. Implementing RPC Pattern
- Example: JSON-RPC 2.0 envelope
- 1. Understanding Publish-Subscribe Pattern
- 2. Implementing Topic Subscription
- Example: Subscribe / unsubscribe
- 3. Managing Subscriber Lists
- 4. Publishing Messages to Topics
- Example: Publish helper
- 5. Implementing Topic Wildcards
- 6. Handling Private Channels
- 7. Implementing Message Filtering
- Example: Predicate filter
- 8. Managing Subscription State
- 9. Implementing Presence
- Example: Presence events
- 10. Handling Subscription Limits
- 1. Tracking Connection State
- 2. Storing Client Data
- Example: Attach context
- 3. Synchronizing State
- 4. Handling State Recovery
- Example: Resume protocol
- 5. Implementing State Snapshots
- 6. Implementing Delta Updates
- Example: JSON Patch (RFC 6902)
- 7. Using Operational Transformation
- 8. Implementing CRDT
- 9. Validating State Consistency
- 10. Persisting State
- 1. Creating Session ID
- 2. Storing Session Data
- 3. Associating Session with Connection
- Example: Bind on upgrade
- 4. Handling Session Expiration
- 5. Implementing Session Persistence
- 6. Managing Multiple Sessions
- 7. Invalidating Sessions
- Example: Force logout
- 8. Sharing Sessions Across Servers
- 9. Implementing Session Heartbeat
- 10. Auditing Session Activity
- 1. Passing Tokens in URL
- Example: Query token
- 2. Using Custom Headers
- Example: Subprotocol token (browser workaround)
- 3. Sending Authentication Message
- Example: Auth-first protocol
- 4. Validating JWT Tokens
- 5. Using Cookie Authentication
- Example: Same-origin cookie
- 6. Implementing OAuth Flow
- OAuth + WebSocket
- 7. Handling Session Management
- 8. Implementing Token Refresh
- Example: Refresh before expiry
- 9. Closing Unauthorized Connections
- 10. Implementing Multi-Factor Authentication
- 1. Defining User Permissions
- 2. Checking Message Permissions
- Example: Per-message check
- 3. Implementing Role-Based Access Control
- 4. Implementing Attribute-Based Access Control
- Example: ABAC predicate
- 5. Validating Topic Access
- 6. Implementing Resource Ownership
- 7. Handling Permission Denied
- 8. Implementing Dynamic Permissions
- 9. Auditing Authorization Events
- 10. Testing Authorization Logic
- 1. Using Secure WebSockets
- 2. Validating Origin Header
- Example: Origin allowlist
- 3. Using TLS Certificates
- 4. Validating Input Data
- 5. Preventing XSS Attacks
- Example: DOMPurify on render
- 6. Implementing CSRF Protection
- 7. Implementing IP Whitelisting
- Example: CIDR check
- 8. Encrypting Messages
- 9. Validating Message Size
- Example: Server limit
- 10. Implementing Security Headers
- 1. Understanding Rate Limiting Need
- 2. Implementing Connection Rate Limiting
- Example: Per-IP connect counter
- 3. Implementing Message Rate Limiting
- 4. Using Token Bucket Algorithm
- Example: Token bucket
- 5. Using Leaky Bucket Algorithm
- 6. Implementing Sliding Window
- Example: Sliding count
- 7. Storing Rate Limit State
- 8. Handling Rate Limit Exceeded
- Example: Reject with hint
- 9. Implementing Per-User Limits
- 10. Monitoring Rate Limit Metrics
- 1. Understanding Connection Pooling Benefits
- 2. Creating Connection Pool
- Example: Simple Node pool
- 3. Acquiring Connections
- 4. Releasing Connections
- 5. Setting Pool Size Limits
- 6. Implementing Connection Validation
- 7. Handling Pool Exhaustion
- 8. Implementing Connection Lifecycle
- Pooled Connection Lifecycle
- 9. Monitoring Pool Metrics
- 10. Testing Pool Behavior
- 1. Understanding Memory Challenges
- 2. Preventing Memory Leaks
- 3. Using Weak References
- Example: WeakMap context
- 4. Implementing Connection Cleanup
- Example: Centralized teardown
- 5. Monitoring Memory Usage
- 6. Limiting Buffer Sizes
- 7. Implementing Message Expiration
- Example: TTL on queued message
- 8. Garbage Collection Considerations
- 9. Profiling Memory
- 10. Handling Out of Memory
- 1. Minimizing Message Size
- 2. Batching Messages
- 3. Using Binary Format
- 4. Implementing Message Throttling
- Example: requestAnimationFrame throttle
- 5. Optimizing JSON Parsing
- 6. Reusing Buffers
- Example: Buffer pool
- 7. Reducing Event Listener Overhead
- 8. Implementing Lazy Parsing
- 9. Profiling WebSocket Performance
- 10. Load Testing Connections
- 1. Understanding Scaling Challenges
- 2. Using Redis Pub/Sub
- Example: Redis fan-out
- 3. Implementing Message Broadcasting
- 4. Sharing Session State
- 5. Implementing Sticky Sessions
- 6. Using Message Queue
- 7. Implementing Service Discovery
- 8. Handling Server Addition/Removal
- Rolling Deploy Drain
- 9. Monitoring Cluster Health
- 10. Testing Scaling Scenarios
- 1. Understanding WebSocket Load Balancing Challenges
- 2. Using Sticky Sessions
- 3. Configuring Layer 4 Load Balancers
- 4. Configuring Layer 7 Load Balancers
- Example: Nginx upstream
- 5. Implementing Client-Side Load Balancing
- 6. Using Connection Draining
- 7. Handling Load Balancer Health Checks
- 8. Implementing Geographic Routing
- 9. Monitoring Connection Distribution
- 10. Testing Failover Scenarios
- 1. Understanding Proxy Challenges
- 2. Configuring Nginx Proxy
- Example: Nginx WS proxy
- 3. Configuring Apache Proxy
- Example: mod_proxy_wstunnel
- 4. Configuring HAProxy
- Example: HAProxy frontend/backend
- 5. Handling Proxy Timeouts
- 6. Implementing Proxy Authentication
- 7. Using CONNECT Method
- 8. Handling Corporate Proxies
- 9. Debugging Proxy Issues
- 10. Testing Proxy Configuration
- 1. Deploying to Cloud Platforms
- 2. Deploying to Heroku
- 3. Deploying to Vercel
- 4. Deploying to DigitalOcean
- 5. Configuring Docker Containers
- Example: Dockerfile
- 6. Setting Environment Variables
- 7. Configuring SSL/TLS Certificates
- 8. Setting Up Process Managers
- 9. Implementing Health Checks
- Example: Liveness vs readiness
- 10. Configuring Auto-Restart
- 1. Implementing Structured Logging
- Example: pino structured
- 2. Logging Connection Events
- 3. Logging Message Events
- 4. Tracking Connection Metrics
- 5. Monitoring Message Throughput
- 6. Tracking Error Rates
- 7. Using Application Performance Monitoring
- 8. Implementing Custom Metrics
- Example: prom-client
- 9. Setting Up Alerts
- 10. Analyzing Logs
- 1. Using Browser DevTools
- 2. Inspecting WebSocket Frames
- 3. Monitoring Connection State
- Example: Console probe
- 4. Logging Messages
- Example: Conditional verbose log
- 5. Using wscat Tool
- Example: wscat session
- 6. Using Postman WebSocket
- 7. Implementing Debug Mode
- 8. Capturing Network Traffic
- 9. Debugging Server Code
- 10. Analyzing Performance Issues
- 1. Writing Unit Tests
- 2. Mocking WebSocket API
- Example: mock-socket
- 3. Testing Message Handlers
- 4. Testing Reconnection Logic
- Example: Simulate disconnect
- 5. Writing Integration Tests
- 6. Using WebSocket Test Server
- 7. Testing Error Scenarios
- 8. Load Testing
- Example: k6 script
- 9. Testing Security
- 10. Implementing E2E Tests
- 1. Handling Simultaneous Connections
- 2. Handling Connection Migration
- 3. Handling Server Restart
- Server Restart Sequence
- 4. Handling Clock Skew
- 5. Handling Message Reordering
- 6. Handling Partial Messages
- 7. Handling Unicode Characters
- 8. Handling Empty Messages
- 9. Handling Connection Limits
- 10. Handling Memory Leaks
- 1. Implementing Custom Extension
- 2. Modifying Frame Headers
- 3. Transforming Payload Data
- 4. Negotiating Extension Parameters
- Example: Extension offer with params
- 5. Handling Extension Conflicts
- 6. Implementing Custom Framing
- 7. Testing Extension Compatibility
- 8. Documenting Extension Behavior
- 9. Versioning Extensions
- 10. Understanding Extension Security
- 1. Implementing Chat Application
- Example: Chat envelope
- 2. Implementing Live Notifications
- 3. Implementing Real-Time Dashboard
- 4. Implementing Collaborative Editing
- Example: Yjs over WebSocket
- 5. Implementing Live Location Tracking
- 6. Implementing Live Comments
- 7. Implementing Game Multiplayer
- 8. Implementing Live Audio/Video Signaling
- 9. Implementing Live Cursor Sharing
- Example: Throttled cursor
- 10. Implementing Real-Time Analytics
- 1. Detecting WebSocket Support
- Example: Capability check
- 2. Implementing Long Polling Fallback
- 3. Implementing SSE Fallback
- Example: EventSource
- 4. Using Socket.IO Transports
- Example: Socket.IO client
- 5. Implementing Graceful Degradation
- 6. Handling Mixed Connections
- 7. Testing Fallback Mechanisms
- 8. Implementing Progressive Enhancement
- 9. Communicating Fallback Status
- 10. Monitoring Fallback Usage
- 1. Handling Mobile Network Issues
- 2. Implementing Background Connection
- 3. Reducing Battery Consumption
- 4. Handling App Suspension
- Example: visibilitychange
- 5. Optimizing for Slow Networks
- 6. Implementing Offline Support
- 7. Handling Network Type Changes
- 8. Using Page Visibility API
- 9. Testing on Mobile Devices
- 10. Monitoring Mobile Performance
- 1. Using WebSocket in React
- Example: useWebSocket hook (React 18+)
- 2. Using WebSocket in Vue.js
- Example: Vue 3 composable
- 3. Using WebSocket in Angular
- Example: Angular 17+ service
- 4. Using WebSocket in Node.js
- 5. Using WebSocket in Python
- Example: websockets (3.12+ asyncio)
- 6. Using WebSocket in Go
- Example: gorilla/websocket (Go 1.21+)
- 7. Using WebSocket in Java
- Example: Spring Boot (Java 21+)
- 8. Using WebSocket in Rust
- 9. Using WebSocket in Worker Threads
- Example: SharedWorker WS bridge
- 10. Using WebSocket in Service Workers