go-gemini/examples/stream.go
2021-02-17 20:35:27 -05:00

81 lines
1.5 KiB
Go

// +build ignore
// This example illustrates a streaming Gemini server.
package main
import (
"context"
"crypto/tls"
"crypto/x509/pkix"
"fmt"
"log"
"time"
"git.sr.ht/~adnano/go-gemini"
"git.sr.ht/~adnano/go-gemini/certificate"
)
func main() {
var server gemini.Server
if err := server.Certificates.Load("/var/lib/gemini/certs"); err != nil {
log.Fatal(err)
}
server.GetCertificate = func(hostname string) (tls.Certificate, error) {
return certificate.Create(certificate.CreateOptions{
Subject: pkix.Name{
CommonName: hostname,
},
DNSNames: []string{hostname},
Duration: 365 * 24 * time.Hour,
})
}
var mux gemini.ServeMux
mux.HandleFunc("/", stream)
server.Handler = &mux
if err := server.ListenAndServe(); err != nil {
log.Fatal(err)
}
}
// stream writes an infinite stream to w.
func stream(w gemini.ResponseWriter, r *gemini.Request) {
flusher, ok := w.(gemini.Flusher)
if !ok {
w.WriteHeader(gemini.StatusTemporaryFailure, "Internal error")
return
}
ch := make(chan string)
ctx, cancel := context.WithCancel(context.Background())
go func(ctx context.Context) {
for {
select {
case <-ctx.Done():
return
default:
ch <- fmt.Sprint(time.Now().UTC())
}
time.Sleep(time.Second)
}
// Close channel when finished.
// In this example this will never be reached.
close(ch)
}(ctx)
for {
s, ok := <-ch
if !ok {
break
}
fmt.Fprintln(w, s)
if err := flusher.Flush(); err != nil {
cancel()
return
}
}
}