Code Explainers

Go code explainers

go 
package feed
 
import (
	"encoding/json"

Streaming a JSON array in Go

streaming json decoder
Intermediate 6 steps
go 
package validate
 
import (
	"fmt"

Struct validation with reflection in Go

reflection struct-tags validation
Intermediate 7 steps
go 
package middleware
 
import (
	"bytes"

Verifying webhook HMAC signatures in Gin

hmac middleware webhooks
Intermediate 7 steps
go 
package handlers
 
import (
	"fmt"

Handling secure file uploads in Gin

file-upload validation security
Intermediate 7 steps
go 
package server
 
import (
	"net/http"

Serving a single-page app with Gin

static-files spa routing
Intermediate 7 steps
go 
package handlers
 
import (
	"fmt"

Handling multipart profile uploads in Gin

form binding file upload validation
Intermediate 7 steps
go 
package metrics
 
import (
	"sync/atomic"

A lock-free request counter in Go

concurrency atomics lock-free
Intermediate 6 steps
go 
package middleware
 
import (
	"time"

Building a request logger middleware in Gin

middleware structured-logging closures
Intermediate 6 steps
go 
package fetch
 
import (
	"context"

Concurrent API fetches with errgroup in Go

concurrency goroutines error-handling
Intermediate 8 steps
go 
func UploadFiles(c *gin.Context) {
	form, err := c.MultipartForm()
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid multipart form"})

Handling multi-file uploads in Gin

file-upload multipart validation
Intermediate 8 steps
go 
package pipeline
 
import (
	"context"

A cancelable worker pool in Go

concurrency channels worker-pool
Advanced 8 steps
go 
package auth
 
import (
	"net/http"

Building a JWT auth middleware in Gin

middleware jwt authentication
Intermediate 7 steps
go 
func RecoveryHandler(logger *zap.Logger) gin.HandlerFunc {
	return gin.CustomRecovery(func(c *gin.Context, recovered any) {
		var brokenPipe bool
		if ne, ok := recovered.(*net.OpError); ok {

A panic-recovery middleware in Gin

middleware panic-recovery structured-logging
Intermediate 6 steps
go 
package server
 
import (
	"context"

Composing HTTP middleware in Go

middleware http-handlers closures
Intermediate 8 steps
go 
package config
 
import (
	"encoding/json"

Parsing untyped JSON config in Go

json parsing type assertions error handling
Intermediate 7 steps
go 
package main
 
import (
	"net/http"

How route groups nest in Gin

routing middleware api versioning
Intermediate 6 steps
go 
package main
 
import (
	"errors"

Parsing and validating CLI flags in Go

cli-parsing validation error-handling
Intermediate 8 steps
go 
package cache
 
import (
	"container/list"

Building a generic LRU cache in Go

lru-cache generics linked-list
Intermediate 8 steps