Code Explainers

Code explainers tagged #caching

rust 
use axum::{extract::{Path, State}, http::StatusCode, Json};
use dashmap::DashMap;
use serde::Serialize;
use std::sync::Arc;

Request coalescing in an Axum handler

caching concurrency request-coalescing
Advanced 8 steps
go 
package cache
 
import (
	"sync"

A thread-safe TTL cache in Go

concurrency mutex caching
Intermediate 9 steps
go 
package middleware
 
import (
	"bytes"

Idempotent requests in Gin with Redis

idempotency caching middleware
Advanced 10 steps
java 
public class RequestCoalescer<K, V> {
 
    private final ConcurrentHashMap<K, CompletableFuture<V>> inFlight = new ConcurrentHashMap<>();
    private final Function<K, V> loader;

Coalescing duplicate requests in Java

concurrency caching completablefuture
Advanced 6 steps
php 
<?php
 
namespace App\Services;
 

Caching per-tenant settings in Laravel

caching multi-tenancy dependency-injection
Intermediate 7 steps
php 
<?php
 
namespace App\Http\Middleware;
 

Idempotency keys in Laravel middleware

idempotency middleware caching
Advanced 8 steps
typescript 
type CurrencyFormatOptions = {
  locale?: string;
  currency: string;
  showDecimals?: boolean;

Caching Intl.NumberFormat for currency

memoization internationalization caching
Intermediate 9 steps
php 
<?php
 
namespace App\Models;
 

Debouncing Eloquent jobs in Laravel

debounce model-events queued-jobs
Advanced 7 steps
php 
<?php
 
namespace App\Services;
 

Tagged cache invalidation in Laravel

caching cache-tags invalidation
Intermediate 5 steps
javascript 
const crypto = require('crypto');
 
function inMemoryCache({ maxAge = 60_000, maxEntries = 500 } = {}) {
  const store = new Map();

Building an in-memory cache middleware in Express

caching middleware etag
Advanced 10 steps
ruby 
class DashboardMetrics
  CACHE_TTL = 15.minutes
 
  def initialize(account)

Caching dashboard metrics in Rails

caching service-object query-optimization
Intermediate 5 steps
ruby 
class LRUCache
  def initialize(capacity)
    raise ArgumentError, "capacity must be positive" unless capacity.positive?
 

How an LRU cache works in Ruby

caching eviction hash-ordering
Intermediate 7 steps
python 
import json
import hashlib
from datetime import timedelta
 

Idempotent payment endpoints in FastAPI

idempotency redis distributed-locking
Advanced 9 steps
php 
<?php
 
namespace App\Http\Middleware;
 

Idempotent requests with Laravel middleware

idempotency middleware caching
Advanced 8 steps
python 
from django.contrib.postgres.search import SearchQuery, SearchRank, SearchVector
from django.core.cache import cache
from django.db.models import F
from django.http import JsonResponse

Ranked full-text search in Django

full-text-search debouncing caching
Advanced 9 steps
go 
func ServeVideo(c *gin.Context) {
	id := c.Param("id")
	video, err := videoRepo.FindByID(c.Request.Context(), id)
	if err != nil {

Streaming video files with Gin

http streaming range requests file serving
Intermediate 6 steps
php 
<?php
 
namespace App\Cache;
 

A content-hashed fragment cache in PHP

caching content-hashing atomic-writes
Intermediate 10 steps
typescript 
import { Injectable, OnModuleInit, Logger } from '@nestjs/common';
import { ConfigService } from '@nestjs/config';
import { Cron, CronExpression } from '@nestjs/schedule';
 

A self-refreshing feature flags provider in NestJS

caching scheduled-tasks dependency-injection
Intermediate 8 steps