Thin web service library.
Given a listen address, certificate directory, user name and data directory:
- If certificate directory is not blank, reads
fullchain.pemandprivkey.pemfrom it. - If the listen address does not specify a port, default port depends on initial user privileges and if we have a certificate.
- Starts listening on the address and port.
- If user name is given, switch to that user.
- If data directory is given, create it if needed.
- When serving, listen for SIGINT and SIGTERM and do a controlled shutdown.
go get github.com/linkdata/webserv
package main
import (
"context"
"flag"
"log/slog"
"net/http"
"os"
"github.com/linkdata/webserv"
)
var (
flagAddress = flag.String("address", os.Getenv("WEBSERV_ADDRESS"), "serve HTTP requests on given [address][:port]")
flagCertDir = flag.String("certdir", os.Getenv("WEBSERV_CERTDIR"), "where to find fullchain.pem and privkey.pem")
flagUser = flag.String("user", envOrDefault("WEBSERV_USER", "www-data"), "switch to this user after startup (*nix only)")
flagDataDir = flag.String("datadir", envOrDefault("WEBSERV_DATADIR", "$HOME"), "where to store data files after startup")
flagListenURL = flag.String("listenurl", os.Getenv("WEBSERV_LISTENURL"), "specify the external URL clients can reach us at")
)
func envOrDefault(envvar, defval string) (s string) {
if s = os.Getenv(envvar); s == "" {
s = defval
}
return
}
func main() {
flag.Parse()
cfg := webserv.Config{
Address: *flagAddress,
CertDir: *flagCertDir,
User: *flagUser,
DataDir: *flagDataDir,
ListenURL: *flagListenURL,
Logger: slog.Default(),
}
http.DefaultServeMux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
_, _ = w.Write([]byte("<html><body>Hello world!</body></html>"))
})
l, err := cfg.Listen()
if err == nil {
if err = cfg.Serve(context.Background(), l, nil); err == nil {
return
}
}
slog.Error(err.Error())
}