Timeout

The timeout pattern is used to limit the amount of time an operation can take. If the operation doesn’t complete within the specified time, it is aborted or handled appropriately.

This pattern is particularly useful for network requests, database queries, or any long-running processes that must not block indefinitely.

Example 1: Using context.WithTimeout

package main

import (
	"context"
	"fmt"
	"time"
)

func longRunningOperation(ctx context.Context) error {
	select {
	case <-time.After(5 * time.Second): // Simulates long work
		return nil
	case <-ctx.Done(): // Context timeout/cancellation
		return ctx.Err()
	}
}

func main() {
	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
	defer cancel()

	err := longRunningOperation(ctx)
	if err != nil {
		fmt.Println("Operation failed:", err)
	} else {
		fmt.Println("Operation completed successfully")
	}
}

Example 2: Using select with time.After

package main

import (
	"fmt"
	"time"
)

func main() {
	resultChan := make(chan string)

	go func() {
		time.Sleep(3 * time.Second) // Simulate work
		resultChan <- "Success"
	}()

	select {
	case result := <-resultChan:
		fmt.Println("Received:", result)
	case <-time.After(2 * time.Second):
		fmt.Println("Timeout! Operation took too long.")
	}
}