When it comes to custom Hook patterns in React Hooks, many developers only operate at the API-call level. This article tries to look at the problems you'll actually run into and their solutions from a production perspective.
Basic Principles
Building on this, we can optimize further:
import { useReducer, useCallback } from 'react'
const initialState = { items: [], filter: '', sort: 'date' }
function reducer(state, action) {
switch (action.type) {
case 'SET_ITEMS': return { ...state, items: action.payload }
case 'SET_FILTER': return { ...state, filter: action.payload }
case 'ADD_ITEM': return { ...state, items: [...state.items, action.payload] }
case 'REMOVE_ITEM': return { ...state, items: state.items.filter(i => i.id !== action.payload) }
default: throw new Error(`Unknown: ${action.type}`)
}
}
This pattern is very useful in large projects and noticeably lowers maintenance cost.
Advanced Features
In real projects, usage gets a bit more complex:
import { useReducer, useCallback } from 'react'
const initialState = { items: [], filter: '', sort: 'date' }
function reducer(state, action) {
switch (action.type) {
case 'SET_ITEMS': return { ...state, items: action.payload }
case 'SET_FILTER': return { ...state, filter: action.payload }
case 'ADD_ITEM': return { ...state, items: [...state.items, action.payload] }
case 'REMOVE_ITEM': return { ...state, items: state.items.filter(i => i.id !== action.payload) }
default: throw new Error(`Unknown: ${action.type}`)
}
}
This way, both the testability and extensibility of the code improve.
Project Practice
Here is a complete example:
import { useReducer, useCallback } from 'react'
const initialState = { items: [], filter: '', sort: 'date' }
function reducer(state, action) {
switch (action.type) {
case 'SET_ITEMS': return { ...state, items: action.payload }
case 'SET_FILTER': return { ...state, filter: action.payload }
case 'ADD_ITEM': return { ...state, items: [...state.items, action.payload] }
case 'REMOVE_ITEM': return { ...state, items: state.items.filter(i => i.id !== action.payload) }
default: throw new Error(`Unknown: ${action.type}`)
}
}
Pay attention to edge-case handling — it's critical in production.
Best Practices
The key is understanding the core logic:
import { useReducer, useCallback } from 'react'
const initialState = { items: [], filter: '', sort: 'date' }
function reducer(state, action) {
switch (action.type) {
case 'SET_ITEMS': return { ...state, items: action.payload }
case 'SET_FILTER': return { ...state, filter: action.payload }
case 'ADD_ITEM': return { ...state, items: [...state.items, action.payload] }
case 'REMOVE_ITEM': return { ...state, items: state.items.filter(i => i.id !== action.payload) }
default: throw new Error(`Unknown: ${action.type}`)
}
}
Performance optimization has to be tied to the specific scenario — not every case calls for over-optimizing.
Common Pitfalls
Here's one way we can improve on this:
import { useReducer, useCallback } from 'react'
const initialState = { items: [], filter: '', sort: 'date' }
function reducer(state, action) {
switch (action.type) {
case 'SET_ITEMS': return { ...state, items: action.payload }
case 'SET_FILTER': return { ...state, filter: action.payload }
case 'ADD_ITEM': return { ...state, items: [...state.items, action.payload] }
case 'REMOVE_ITEM': return { ...state, items: state.items.filter(i => i.id !== action.payload) }
default: throw new Error(`Unknown: ${action.type}`)
}
}
This approach has been running stably in production for over half a year and has proven itself in practice.
Summary
- Don't adopt new tech just for the sake of using it
- The code examples are for reference only and should be adapted to your actual use case
- Custom Hook patterns aren't a silver bullet — choose based on your project's scale and tech stack
- Understanding the underlying principles matters more than memorizing APIs
