API Reference

Farrow provides a complete set of APIs for building type-safe web applications. This documentation provides detailed API reference for all core modules.

Core Modules

farrow-http

TypeScript-first Web Framework - Provides type-safe routing and automatic validation

• HTTP/HTTPS server creation and configuration
• Type-safe routing patterns and automatic validation
• Powerful Response builder system
• Modular router and middleware system
• Context management and error handling
• Static file serving and CORS integration
• Express integration support

farrow-schema

Powerful Type Validation and Serialization Library - Handle data easily through type-driven design

• Complete basic type system (String, Number, Boolean, Date, ID)
• Flexible composite types (List, Optional, Nullable, Record, Tuple)
• Structured type definitions (ObjectType, Struct)
• Union and intersection types (Union, Intersect, Literal)
• Schema manipulation tools (pickObject, omitObject, partial, required)
• Built-in and custom validator system
• Complete TypeScript type inference support

farrow-pipeline

Type-safe Middleware Pipeline Library - Provides functional programming style request processing

• Synchronous and asynchronous Pipeline creation
• Type-safe context management system
• Container concept and dependency injection
• Pipeline composition and middleware execution
• Utilities and error handling
• Async tracing support

Quick Navigation

HTTP Service

Core API

• HTTP Server - Http(), Https(), configuration options
• Router System - Router(), HTTP method routing
• Request & Validation - RequestInfo, automatic validation
• Response Building - Response object and methods
• Middleware System - Onion model, execution order

Advanced Features

• Context Management - Context system, request hooks
• Error Handling - HttpError, global error handling
• Utilities - ParseUrl, type tools
• Best Practices - Dependency injection, testing strategies

Schema Validation

Type System

• Basic Type Schemas - String, Number, Boolean, Date, ID, Int, Float
• Composite Type Schemas - List, Optional, Nullable, Record, Tuple
• Structured Type Schemas - ObjectType, StructType, Union, Intersect, Literal
• Special Type Schemas - Any, Unknown, Never, Json

Validation & Formatting

• Validator System - Runtime data validation
• Formatter System - Type metadata extraction
• Result Type - Functional error handling

Helper Tools

• field - Field metadata definition
• pick series - Select fields
• omit series - Exclude fields
• partial series - Convert to optional
• required series - Convert to required

Pipeline System

Core Features

• Pipeline Type System - createPipeline, createAsyncPipeline
• Middleware Types - Middleware, Next, MiddlewareInput
• usePipeline - Run sub-Pipeline with inherited container

Context System

• Context System - createContext, context methods
• Container System - createContainer, container methods
• AsyncTracer - Async context propagation

API Conventions

Naming Conventions

• Types: PascalCase (e.g., ObjectType, HttpError)
• Functions: camelCase (e.g., createContext, pickStruct)
• Constants: UPPER_CASE (e.g., DEFAULT_PORT)
• Files: kebab-case (e.g., farrow-http)

Type Annotations

All APIs include complete TypeScript type definitions:

// Function signature
function createContext<T>(defaultValue: T): Context<T>

// Type definition
type RequestInfo = {
  readonly pathname: string
  readonly method?: string
  readonly query?: RequestQuery
  readonly body?: any
  readonly headers?: RequestHeaders
  readonly cookies?: RequestCookies
}