Learn NodeJS Hard Way

Description

To master a new concept, it’s often best to begin from the ground up. This isn’t just another Node.js guide; it’s a comprehensive, code-along experience aimed at building a real world product that may be used by thousands of developers. The product that we’re going to build will be a backend framework, that too from scratch.

You won’t just learn how Node.js works, but also why it operates in a particular way. The guide also includes discussions on relevant data structures and design patterns.

The book also includes a wide range of exercises specifically created to challenge you, that may require commitment and consistent effort on your part. The first exercises starts from chapter 7

This guide goes beyond the basics. We’re focused on delivering a modular, optimized backend framework that is close to being production-ready. Topics like performance optimization, security measures, and various testing approaches will be covered to ensure the framework is both reliable and extendable.

I highly recommend actively coding alongside this guide, rather than just reading through it, for a full understanding of Node.js and its more intricate aspects.

Table of Contents

• (optional) Node.js is way faster than you think
  • Contenders for the test
    • Elysia - Bun
    • Axum - Rust
    • Express - Node.js
    • Velocy - Node.js
  • The benchmark
• What the hell is a web server any way?
  • Parts of a Web Server
  • Navigating the World of Protocols: A Quick Overview
  • The Relationship Between HTTP and TCP
    • Data Integrity and Order
    • Acknowledgment Mechanism
    • Complex Interactions
    • Transmission Overhead
  • How Web Servers Respond to Your Requests
    • The Request
      • Your Request
      • Finding the Address
      • Resolving the Address
    • The Response
      • Return Address
      • Sending the Request
      • Preparing the Content
      • Sending the Response
      • Enjoying the Content
• Your first web server with node.js
  • What exactly is node or nodejs?
  • Your first node.js program
  • How does console.log() work in Node.js?
  • The process Object
  • The stdout property of the process object
• Working with files
  • What will the logging library do
  • How do you work with files anyway?
  • Let’s get back to files
  • A little more about file descriptors
  • Creating our first file
    • path argument
    • flag argument
    • mode argument
  • Reading from a file
  • A small primer to for..of and for await..of in javascript
    • for..of
    • for await..of
  • Reading the json file
  • Buffers
  • Parsing the json file
• logtar - Our Own logging library
  • Initializing a new project
  • A little about SemVer
  • Creating a LogLevel class
  • The Logger class
  • Encapsulation with private fields
  • The LogConfig class
  • Design Patterns
    • The Builder pattern
    • Using the Builder pattern with the LogConfig class
  • jsdoc comments
  • The RollingConfig class
    • The RollingSizeOptions class
    • The RollingTimeOptions class
  • Finishing up the RollingConfig class
  • Let’s recap
  • Adding more useful methods in the LogConfig class
  • Why readFileSync?
• Refactoring the code
  • The need for refactoring
  • Creating Separate Files
    • Explanation
    • index.js file
    • lib/logtar.js file
    • lib/logger.js file
    • lib/config/log-config.js file
    • lib/config/rolling-config.js file
    • lib/utils/log-level.js file
    • lib/utils/rolling-options.js class
• Writing Logs
  • Re-using the file handle
  • Log rotation
  • Asynchronous logging
  • Getting caller information
  • Testing our current API
  • Implementing logging methods
    • DRY (Don’t Repeat Yourself)
    • The log method
    • Considering the log_level member variable
  • Writing to a file
    • A small primer on Regular Expressions
    • Testing the log file creation
    • Another gotcha
    • Logs directory configuration
    • Our first script
  • The require object
  • Adding a new helper to create log directory
  • Updating the init method
  • Completing the log method
• Capturing metadata
  • What is a stack
  • Examples of stacks
  • The call stack
  • Getting the stack info
  • Getting the callee name and the line number
  • A more ergonomic way
  • Using the get_caller_info function
• A small intro to async vs sync
  • The Balance between Opposites
  • Mixing Asynchronous and Synchronous Code
  • Faster I/O out of the box
  • Blocking Code
  • Concurrency
• Adding Rolling File Support
  • Rolling features
    • #time_threshold
    • #size_threshold
  • The rolling_check() method
  • file_handle.stat()
  • Calling the rolling_check method
  • A big gotcha!
  • Stack traces across await points
    • The culprit
  • Testing the new Log file creation
• HTTP Deep Dive
  • A small web server
    • Starting our web server
    • Testing our web server
    • Testing with cURL
• HTTP Verbs, Versioning and the benefits of HTTP/1.1
  • GET - Retrieve data
  • POST - Create something
  • PUT - Replace or create
  • HEAD - Retrieve metadata
  • DELETE - Remove from existence
  • PATCH - Partial updates
  • A small recap
  • The / path
  • HTTP/0.9
  • HTTP/1.0
    • Introduction to the HTTP Header
    • Versioning
    • Status Codes
    • Content-Type Header
    • New Methods
  • HTTP/1.1
    • Persistent Connections
    • Pipelining
    • Chunked Transfer Encoding
    • The Host header
    • Caching improvements
    • Range Requests
    • New Methods: PUT, DELETE, CONNECT, OPTIONS, TRACE
• User Agents
  • User-Agent can be weird
• MIME Type and Content-Type
  • Understanding the Accept Header
    • Breaking Down the Line
    • Why the Wildcard?
    • Server Response
  • Mime Type
  • Anatomy of a MIME type
  • But why the wildcard /?
  • The Content-Type header
    • Content-Type on request header
    • Content-Type on response header
  • The charset=UTF-8: character encoding
    • Universal Character Encoding
• Headers
  • Header Name
  • Colon (:)
  • Header Value
  • Whitespace
  • Custom X- based headers
• Request headers
  • Accept
  • Referer
  • Authorization
  • Cookie
  • Host
  • Content-Type
• Response Headers
  • Content-Type (response)
  • Cache-Control
    • How Caches Work
    • Cache-Control Directives
      • Always Cache (infrequent updates)
      • Always Cache (private only)
      • Never Cache (realtime data)
  • Set-Cookie
• Response and Status Codes
  • Connection: close in action
  • Status Codes
• velocy our backend framework
  • Why velocy?
  • What is a backend framework/library anyway?
  • Core features of our backend framework
    • Routing and URL Handling
    • Middlewares
    • Building our own database
      • Data Storage and Retrieval
      • Indexing
      • Querying
    • Caching
    • Rate limiting
    • Other features
      • Shared state
      • File uploads
      • Static file serving
      • Multi-part data
      • Websockets
      • Logging
      • Monitoring
• A basic Router implementation
  • A Toy Router
  • Chunks, oh no!
  • Specifying Content-Length
  • Code reusability
  • Separation of Concerns
• The Router class
  • Using Router with an HTTP server
  • this is not good
    • Using .bind()
    • Using Arrow function
  • Lexical context
  • Arrow functions are not free
  • Why should we care about memory?
  • Testing the updated code
• Improving the Router API
• The need for a trie
  • What is a Trie anyway?
• Exercise 1 - Implementing a Trie
  • Root Node
  • End of the word
  • Challenge 1: Basic Trie with insert Method
    • Requirements
    • More details
    • Solution
  • Challenge 2: Implement search method
    • Requirements
    • More details
    • Hints
    • Solution
• Exercise 2 - Implementing our Trie based Router
  • Challenge 1: Implementing the addRoute method
    • Requirements
    • More details
    • Hints
    • Solution
    • Explanation
  • Challenge 2: Implementing the findRoute method
    • Requirements
    • More details
    • Starting Boilerplate
    • Hints
    • Solution
    • Explanation