Where in the code is log writing usually performed?

Logging in a Go application is usually done at points where an important event or error occurs — for example, in error handlers, entry points of functions, when interacting with external services, or when changing the application's state. Logging is often centralized using a separate package or middleware to ensure consistency and ease of log management.

Example of logging in Go:

package main

import (
    "log"
)

func main() {
    log.Println("Application started")
    err := doSomething()
    if err != nil {
        log.Printf("Error: %v", err)
    }
}

func doSomething() error {
    // some logic
    return nil
}

Thus, log entries are typically placed in key locations where it is important to track the application's state or errors.