What are some usage examples of the context package in Go?

What are some usage examples of the context package in Go?

The context package in Go is used for managing deadlines, cancellation signals, and request-scoped values. Here are a few examples:

1. HTTP Requests: You can use context to set a timeout for an HTTP request.
2. Goroutines: Pass a context to goroutines to allow them to be cancelled when the parent context is done.
3. Database Queries: Use context to control the lifetime of database queries.

Can you show me a code example for using context with HTTP requests?

Sure! Here's a simple example:

package main

import (
    "context"
    "fmt"
    "net/http"
    "time"
)

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

    req, err := http.NewRequestWithContext(ctx, "GET", "https://example.com", nil)
    if err != nil {
        fmt.Println(err)
        return
    }

    resp, err := http.DefaultClient.Do(req)
    if err != nil {
        fmt.Println(err)
        return
    }
    defer resp.Body.Close()

    fmt.Println("Response status:", resp.Status)
}

What happens if the context times out?

If the context times out, the HTTP request will be cancelled, and you'll receive an error indicating that the context deadline has been exceeded. This helps prevent hanging requests and allows your application to handle timeouts gracefully.