codesnips

backend

typescript 
export class AppError extends Error {
  public readonly statusCode: number;
  public readonly code: string;
  public readonly isOperational: boolean;

  constructor(message: string, statusCode = 500, code = 'INTERNAL_ERROR', isOperational = true) {

Backend: normalize errors with a single Express handler

express error-handling typescript
by codesnips 4 tabs
javascript 
const Busboy = require('busboy');
const { storeFile } = require('./storage');

function parseMultipart(req, { maxFileSize = 20 * 1024 * 1024 } = {}) {
  return new Promise((resolve, reject) => {
    const busboy = Busboy({

Streaming Multipart Form Upload Parser Using Busboy in Node.js

nodejs multipart streaming
by codesnips 3 tabs
javascript 
class DeadlineError extends Error {
  constructor(message = 'request deadline exceeded') {
    super(message);
    this.name = 'DeadlineError';
    this.code = 'DEADLINE_EXCEEDED';
  }

Enforce Per-Request Timeouts by Aborting Downstream Fetches with AbortSignal

node fetch abortcontroller
by codesnips 3 tabs
typescript 
import sharp from 'sharp';

export interface Variant {
  name: string;
  width: number;
  quality: number;

Generate WebP Image Thumbnails on Upload with Sharp and Express

express sharp image-processing
by codesnips 3 tabs
javascript 
const express = require('express');
const controller = require('../controllers/userController');

const router = express.Router();

router.use((req, res, next) => {

Versioning an Express API with Router-per-Version Mounts and a Shared Controller Module

express api-versioning rest
by codesnips 4 tabs
python 
CACHES = {
    "default": {
        "BACKEND": "django_redis.cache.RedisCache",
        "LOCATION": "redis://127.0.0.1:6379/1",
        "OPTIONS": {
            "CLIENT_CLASS": "django_redis.client.DefaultClient",

Custom DRF Throttle Class for a Public API With Sliding-Window Rate Limits

django drf rate-limiting
by codesnips 3 tabs
typescript 
import { Injectable, Scope } from '@nestjs/common';
import { DataSource, EntityManager, QueryRunner } from 'typeorm';

@Injectable({ scope: Scope.REQUEST })
export class TransactionContext {
  private queryRunner?: QueryRunner;

Request-Scoped TypeORM QueryRunner Provider for Transactional Writes in NestJS

nestjs typeorm transactions
by codesnips 3 tabs
typescript 
import { Request, Response } from 'express';
import { authenticate } from './auth.service';

export async function login(req: Request, res: Response): Promise<void> {
  const { email, password } = req.body ?? {};

Password hashing with Argon2

security node argon2
by codesnips 3 tabs
javascript 
class TokenBucket {
  constructor(capacity, refillRatePerSec) {
    this.capacity = capacity;
    this.refillRate = refillRatePerSec;
    this.tokens = capacity;
    this.lastRefill = Date.now();

Token Bucket Rate Limiter as Express Middleware

express rate-limiting token-bucket
by codesnips 3 tabs
typescript 
export const PERMISSIONS = {
  READ_POSTS: 'posts:read',
  WRITE_POSTS: 'posts:write',
  DELETE_POSTS: 'posts:delete',
  MANAGE_USERS: 'users:manage',
} as const;

Typed Role-Based Route Guards with Permission Middleware in Express

express authorization rbac
by codesnips 3 tabs
typescript 
import { SetMetadata } from '@nestjs/common';

export const CACHEABLE_KEY = 'cacheable:options';

export type VaryDimension = 'user' | 'tenant' | 'query';

Per-Route Response Caching in NestJS with a Custom CacheInterceptor and Cache Key Builder

nestjs caching interceptors
by codesnips 4 tabs
javascript 
const express = require('express');
const AppError = require('./AppError');
const asyncHandler = require('./asyncHandler');
const errorMiddleware = require('./errorMiddleware');
const UserRepo = require('./UserRepo');

Centralized Express Error Handling with Typed AppError and Async Wrapper

express error-handling middleware
by codesnips 4 tabs