How to implement custom I/O timeouts and deadlines in Go?

To implement custom I/O timeouts and deadlines in Go, you can use the context package along with the net and time packages. Here's a step-by-step guide:

Import the required packages:

import (
	"context"
	"net"
	"time"
)

Create a new context.Context using the context.WithTimeout function:

ctx, cancel := context.WithTimeout(context.Background(), time.Second*5) // Timeout after 5 seconds
defer cancel()

Create a net.Dialer with the desired timeout value:

dialer := &net.Dialer{
	Timeout:   time.Second * 5, // Timeout after 5 seconds
	Deadline:  time.Now().Add(time.Second * 10), // Deadline after 10 seconds
}

Use the context and net.Dialer to establish a connection:

conn, err := dialer.DialContext(ctx, "tcp", "example.com:80")
if err != nil {
    // handle error
}
defer conn.Close()

You can also set read and write deadlines on the connection if needed:

conn.SetReadDeadline(time.Now().Add(time.Second * 5)) // Read deadline after 5 seconds
conn.SetWriteDeadline(time.Now().Add(time.Second * 5)) // Write deadline after 5 seconds

Now you can perform read and write operations on the connection using the configured timeouts and deadlines:

// Read operation
buffer := make([]byte, 1024)
n, err := conn.Read(buffer)
if err != nil {
    // handle error
}
fmt.Printf("Received %d bytes: %s\n", n, string(buffer[:n]))

// Write operation
_, err := conn.Write([]byte("Hello, server"))
if err != nil {
    // handle error
}

By using the context package and configuring the Timeout and Deadline properties in the net.Dialer, you can easily implement custom I/O timeouts and deadlines in Go. The context.WithTimeout function allows you to create a timeout context, ensuring that operations are canceled if they exceed the specified timeout duration.