Code Explainers

Code explainers tagged #validation

python 
import os
import uuid
 
from flask import Blueprint, current_app, jsonify, request

Handling secure file uploads in Flask

file-upload validation blueprints
Intermediate 8 steps
php 
<?php
 
namespace App\Http\Requests;
 

Normalizing input in a Laravel FormRequest

validation authorization input-normalization
Intermediate 6 steps
javascript 
import { parsePhoneNumberFromString } from 'libphonenumber-js';
 
export class PhoneValidationError extends Error {
  constructor(message, code) {

Normalizing phone numbers with typed errors

validation error-handling custom-errors
Intermediate 6 steps
python 
import os
from datetime import datetime, timezone
 
import jwt

JWT bearer auth as a FastAPI dependency

authentication jwt dependency-injection
Intermediate 7 steps
php 
public function importCustomers(UploadedFile $file): array
{
    $errors = [];
    $imported = 0;

Validating a CSV import in Laravel

csv-parsing validation error-accumulation
Intermediate 8 steps
javascript 
const express = require('express');
const { z } = require('zod');
const router = express.Router();
 

Validating query params with Zod in Express

validation schema-parsing query-building
Intermediate 9 steps
python 
from datetime import datetime
from fastapi import APIRouter, Depends, HTTPException, status
from pydantic import BaseModel, ConfigDict, EmailStr
from sqlalchemy.orm import Session

Building a users router in FastAPI

routing serialization dependency-injection
Intermediate 7 steps
python 
import re
 
from django.core.exceptions import ValidationError
from django.core.validators import RegexValidator

Building a deconstructible validator in Django

validation regex deconstructible
Intermediate 7 steps
rust 
use std::path::PathBuf;
 
use clap::{Parser, Subcommand, ValueEnum};
 

Building a CLI with clap's derive macros

cli derive-macros argument-parsing
Intermediate 10 steps
php 
<?php
 
declare(strict_types=1);
 

A single-action JSON user controller in PHP

invokable-class json-api validation
Intermediate 7 steps
java 
public final class ShippingAddress {
    private final String recipient;
    private final String line1;
    private final String line2;

Building immutable objects with the Builder pattern

builder-pattern immutability validation
Intermediate 7 steps
javascript 
export function buildPaginationUrl(baseUrl, { page, perPage, filters = {}, sort } = {}) {
  const url = new URL(baseUrl);
  const params = url.searchParams;
 

Building and parsing pagination URLs

url-parsing query-string pagination
Intermediate 8 steps
python 
import re
from email_validator import validate_email, EmailNotValidError
 
_DISPOSABLE_DOMAINS = {

Normalizing signup emails in Python

validation normalization data-cleaning
Intermediate 8 steps
go 
package validate
 
import (
	"fmt"

Struct validation with reflection in Go

reflection struct-tags validation
Intermediate 7 steps
python 
from datetime import datetime
from zoneinfo import ZoneInfo
 
 

Timezone-safe datetime handling in Python

timezones datetime normalization
Intermediate 4 steps
python 
import shutil
import uuid
from pathlib import Path
 

Safe avatar uploads in FastAPI

file-upload validation streaming
Intermediate 8 steps
go 
package handlers
 
import (
	"fmt"

Handling secure file uploads in Gin

file-upload validation security
Intermediate 7 steps
go 
package handlers
 
import (
	"fmt"

Handling multipart profile uploads in Gin

form binding file upload validation
Intermediate 7 steps