codesnips
ruby 
class Order < ApplicationRecord
  class InvalidTransition < StandardError; end

  enum status: { pending: 0, paid: 1, shipped: 2, cancelled: 3 }

  has_many :order_transitions, -> { order(:created_at) }, dependent: :destroy

Order State Machine With Guarded Transitions and an Audit Trail in Rails

rails state-machine activerecord
by codesnips 3 tabs
go 
package health

import (
	"context"
	"sync"
	"time"

Concurrent Readiness Health Check Endpoint in Go with Timeouts

go health-check readiness
by codesnips 3 tabs
ruby 
class Product < ApplicationRecord
  has_many :reviews, dependent: :destroy

  scope :published, -> { where(published: true) }

  def average_rating

Russian Doll Fragment Caching with Touch Propagation in Rails

rails caching fragment-caching
by codesnips 4 tabs
ruby 
class User < ApplicationRecord
  normalizes :phone, with: ->(value) { PhoneNormalizer.call(value) }, apply_to_nil: false

  validates :phone,
            presence: true,
            uniqueness: { case_sensitive: false },

Normalizing Phone Numbers on Assignment with Rails normalizes and a Custom Serializer

rails activerecord normalization
by codesnips 3 tabs
go 
package logctx

import (
	"context"
	"log/slog"
)

Request-Scoped Structured Logging with slog and Context in Go

go logging slog
by codesnips 3 tabs
rust 
use notify::{Event, RecommendedWatcher, RecursiveMode, Watcher};
use std::path::{Path, PathBuf};
use std::sync::mpsc;

pub fn spawn_watcher(root: &Path) -> notify::Result<(RecommendedWatcher, flume::Receiver<PathBuf>)> {
    let (raw_tx, raw_rx) = mpsc::channel::<notify::Result<Event>>();

Debouncing Rapid Filesystem Events in a Rust Directory Watcher

rust filesystem notify
by codesnips 3 tabs
javascript 
const express = require('express');
const multer = require('multer');
const os = require('os');
const fs = require('fs/promises');
const { parseCsvStream } = require('./csvStreamParser');

Stream and Validate Large CSV Uploads Row-by-Row with Node Streams and Backpressure

nodejs streams csv
by codesnips 3 tabs
go 
package authtransport

import (
	"errors"
	"net/http"
)

Injecting Auth Headers via a Custom http.RoundTripper Decorator in Go

go http middleware
by codesnips 3 tabs
ruby 
require 'set'
require 'json'

class Broadcaster
  def initialize
    @mutex = Mutex.new

Stream Server-Sent Events from a Sinatra Route With Keep-Alive Pings

sinatra sse streaming
by codesnips 3 tabs
python 
import asyncio
from typing import Awaitable, Callable, Dict, TypeVar

T = TypeVar("T")

Coalesce Duplicate In-Flight Requests with an Asyncio Single-Flight Cache

asyncio concurrency caching
by codesnips 3 tabs
typescript 
export interface CartItem {
  id: string;
  name: string;
  price: number;
  quantity: number;
}

Type-Safe Shopping Cart with useReducer, Context, and a useCart Hook

react context usereducer
by codesnips 4 tabs
javascript 
const fs = require('fs');
const readline = require('readline');

async function* streamCsvRows(filePath) {
  const stream = fs.createReadStream(filePath, { encoding: 'utf8' });
  const rl = readline.createInterface({ input: stream, crlfDelay: Infinity });

Stream and Import a Large CSV File Line-by-Line with Node.js readline

nodejs streams readline
by codesnips 3 tabs