Code Explainers

Code explainers tagged #query-building

go 
func ListProducts(c *gin.Context) {
	allowed := map[string]string{
		"category": "category",
		"brand":    "brand",

Safe query filtering in a Gin handler

input-validation whitelisting query-building
Intermediate 7 steps
python 
from flask import Blueprint, jsonify
from marshmallow import Schema, fields, validate, EXCLUDE
from webargs.flaskparser import use_args
 

Validating query params in Flask with webargs

validation schema query-building
Intermediate 10 steps
ruby 
class SearchController < ApplicationController
  def index
    @query = params[:q].to_s.strip
  end

Live search suggestions in a Rails controller

controllers sql-injection query-building
Intermediate 6 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 dataclasses import dataclass
from typing import Optional
 
from sqlalchemy import select, func

Building a pagination helper with SQLAlchemy

pagination dataclass computed-properties
Intermediate 8 steps
ruby 
class ArticlesController < ApplicationController
  DEFAULT_LIMIT = 25
  MAX_LIMIT = 100
 

Cursor-based pagination in a Rails controller

pagination cursor query-building
Intermediate 7 steps
python 
from flask import Blueprint, render_template, request, abort
from sqlalchemy import select
 
from .models import Article

Paginating articles in a Flask Blueprint

pagination blueprints input-validation
Intermediate 6 steps