Code Explainers

Go code explainers

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
go 
package model
 
import (
	"encoding/json"

Custom JSON marshaling in Go

json serialization interfaces
Intermediate 5 steps
go 
func (h *TransactionHandler) ExportCSV(c *gin.Context) {
	ctx := c.Request.Context()
	filters := parseTransactionFilters(c)
 

Streaming a CSV export in Gin

streaming csv-export database-cursor
Intermediate 8 steps
go 
package store
 
import (
	"database/sql"

Wrapping and inspecting errors in Go

error-handling error-wrapping sentinel-errors
Intermediate 8 steps
go 
package main
 
import (
	"context"

Graceful HTTP shutdown in Go

graceful-shutdown signals goroutines
Intermediate 8 steps
go 
package handlers
 
type SignupRequest struct {
	Email           string `json:"email" binding:"required,email"`

Validated signup handler in Gin

request validation error handling http status codes
Intermediate 7 steps
go 
package handlers
 
import (
	"net/http"

Cookie-based sessions in Gin

authentication cookies middleware
Intermediate 7 steps
go 
package validators
 
import (
	"regexp"

Custom validators in Gin

validation sync.once regexp
Intermediate 5 steps
go 
package logfmt
 
import (
	"bytes"

Pooling buffers for logfmt encoding in Go

object-pooling memory-reuse serialization
Intermediate 8 steps
go 
package storage
 
import (
	"bufio"

Streaming file downloads safely in Go

http streaming path-traversal
Intermediate 7 steps
go 
package webhooks
 
import (
	"crypto/hmac"

Verifying GitHub webhooks in Gin

hmac webhooks middleware
Intermediate 6 steps
go 
package middleware
 
import (
	"errors"

Centralized error handling in Gin

middleware error-handling custom-errors
Intermediate 8 steps
go 
package debounce
 
import (
	"sync"

Building a debouncer in Go

concurrency debounce timers
Intermediate 6 steps
go 
package retry
 
import (
	"context"

Retry with exponential backoff in Go

retry exponential-backoff jitter
Intermediate 8 steps
go 
package main
 
import (
	"bufio"

Counting matching lines in Go with bufio

file-io buffered-scanning error-handling
Intermediate 4 steps
go 
package collection
 
func Deduplicate[T comparable](items []T) []T {
	seen := make(map[T]struct{}, len(items))

Generic deduplication in Go

generics deduplication maps
Intermediate 5 steps
go 
func StreamMetrics(c *gin.Context) {
	clientGone := c.Request.Context().Done()
	ticker := time.NewTicker(time.Second)
	defer ticker.Stop()

Streaming server-sent events in Gin

server-sent-events streaming channels
Intermediate 7 steps