How do I handle errors in goroutines?

How do I handle errors in goroutines?

In Go, you can handle errors in goroutines by using channels to communicate errors back to the main goroutine.

Can you show me an example of that?

Sure! You can create a channel for errors and send any errors from the goroutine to that channel. Here's a simple example:

package main

import (
    "fmt"
    "time"
)

func doWork(errChan chan error) {
    // Simulate work
    time.Sleep(1 * time.Second)
    // Simulate an error
    errChan <- fmt.Errorf("an error occurred")
}

func main() {
    errChan := make(chan error)
    go doWork(errChan)

    // Wait for the error
    if err := <-errChan; err != nil {
        fmt.Println("Error received:", err)
    }
}

This will print the error received from the goroutine.

What if I have multiple goroutines?

You can use a sync.WaitGroup to wait for all goroutines to finish and a slice of errors to collect them. Here's an example:

package main

import (
    "fmt"
    "sync"
)

func doWork(wg *sync.WaitGroup, errChan chan error) {
    defer wg.Done()
    // Simulate work and error
    errChan <- fmt.Errorf("an error occurred")
}

func main() {
    var wg sync.WaitGroup
    errChan := make(chan error, 3) // Buffered channel

    for i := 0; i < 3; i++ {
        wg.Add(1)
        go doWork(&wg, errChan)
    }

    wg.Wait()
    close(errChan)

    for err := range errChan {
        fmt.Println("Error received:", err)
    }
}

This will handle errors from multiple goroutines.