Channel

Channel Channel adalah cara utama goroutine berkomunikasi satu sama lain. Prinsip Go: "Do not communicate by sharing memory; instead, share memory by communicat

Channel adalah cara utama goroutine berkomunikasi satu sama lain. Prinsip Go: "Do not communicate by sharing memory; instead, share memory by communicating."

Membuat Channel

// Unbuffered channel
ch := make(chan string)

// Buffered channel (kapasitas 5)
ch2 := make(chan int, 5)

Mengirim dan Menerima

ch := make(chan string)

// Goroutine mengirim data
go func() {
    ch <- "Halo dari goroutine!"
}()

// Main menerima data
pesan := <-ch
fmt.Println(pesan)

Unbuffered channel sebagai alat sinkronisasi: pengirim & penerima bertemu (rendezvous) sebelum data berpindah.

Unbuffered vs Buffered

Unbuffered	Buffered
Send memblokir sampai ada receiver	Send memblokir hanya jika buffer penuh
Sinkron (rendezvous)	Asinkron (sampai buffer penuh)
`make(chan int)`	`make(chan int, 10)`

Channel Direction

// Hanya bisa mengirim
func producer(ch chan<- string) {
    ch <- "data"
}

// Hanya bisa menerima
func consumer(ch <-chan string) {
    data := <-ch
    fmt.Println(data)
}

Range dan Close

ch := make(chan int)

go func() {
    for i := 0; i < 5; i++ {
        ch <- i
    }
    close(ch) // Tutup channel setelah selesai
}()

// Range otomatis berhenti saat channel ditutup
for val := range ch {
    fmt.Println(val)
}

Pattern: Fan-Out / Fan-In

// Multiple goroutine menulis ke satu channel
results := make(chan int)
for i := 0; i < 3; i++ {
    go func(id int) {
        results <- id * 10
    }(i)
}

for i := 0; i < 3; i++ {
    fmt.Println(<-results)
}

Channel — Go