Code Explainers

Go code explainers

go 
package handlers
 
import (
	"net/http"

Struct-level validation for partial updates in Gin

validation struct-tags partial-update
Intermediate 7 steps
go 
package fetcher
 
import (
	"context"

Bounded-concurrency HTTP fetching in Go

concurrency semaphore context-cancellation
Advanced 9 steps
go 
package inventory
 
import (
	"encoding/csv"

Parsing CSV into typed structs in Go

csv-parsing error-wrapping type-conversion
Intermediate 8 steps
go 
package search
 
import (
	"net/url"

Building a query URL from a Filter struct in Go

url-encoding struct-methods input-validation
Intermediate 8 steps
go 
package handlers
 
import (
	"net/http"

Content negotiation in Gin handlers

content-negotiation struct-tags rest-api
Intermediate 4 steps
go 
package ratelimit
 
import (
	"context"

A token bucket rate limiter in Go

rate-limiting concurrency goroutines
Intermediate 7 steps
go 
package handlers
 
type BookURI struct {
	Collection string `uri:"collection" binding:"required,alphanum"`

Validating URI params in a Gin handler

input validation struct binding error handling
Intermediate 7 steps
go 
package cache
 
import (
	"context"

Cache-aside reads with singleflight in Go

caching singleflight concurrency
Advanced 8 steps
go 
package httpx
 
import (
	"net/http"

A retrying HTTP transport in Go

http middleware retry
Intermediate 8 steps
go 
package config
 
import (
	"fmt"

Loading typed config from environment variables in Go

configuration environment-variables type-parsing
Beginner 8 steps
go 
package middleware
 
import (
	"crypto/subtle"

Building an API-key middleware in Gin

middleware authentication dependency-injection
Intermediate 5 steps
go 
package api
 
func RegisterRoutes(r *gin.Engine, deps *Dependencies) {
	r.GET("/health", func(c *gin.Context) {

Layering route groups and middleware in Gin

routing middleware authentication
Intermediate 8 steps
go 
package payments
 
import (
	"context"

Fetching a charge over HTTP in Go

context-timeout http-client json-decoding
Intermediate 6 steps
go 
package scheduler
 
import (
	"context"

A context-aware heartbeat ticker in Go

concurrency channels context
Intermediate 5 steps
go 
package middleware
 
import (
	"compress/gzip"

How gzip response compression works in Gin

middleware compression http
Intermediate 8 steps
go 
package middleware
 
import (
	"context"

Correlation ID tracing middleware in Gin

middleware request tracing structured logging
Intermediate 7 steps
go 
package web
 
import (
	"embed"

Serving embedded static assets in Go

embed static-assets http-handler
Intermediate 8 steps
go 
package pipeline
 
import "sync"
 

The fan-in pattern in Go channels

concurrency channels fan-in
Advanced 8 steps