/
main.go
167 lines (141 loc) · 3.17 KB
/
main.go
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package main
import (
"flag"
"fmt"
"log"
"os"
"os/signal"
"syscall"
"github.com/FlushCapacitor/flush-capacitor/sensors"
)
const (
toiletNameLeft = "L"
toiletNameRight = "R"
toiletStateUnlocked = "unlocked"
toiletStateLocked = "locked"
)
func main() {
if err := run(); err != nil {
log.Fatalln("Error:", err)
}
}
func run() error {
// Parse the flags.
addr := flag.String("listen", "localhost:8080", "network address to listen on")
canonicalUrl := flag.String("canonical_url", "localhost:8080",
"URL to be used to access the server")
rand := flag.Bool("random", false, "trigger sensor changes randomly")
watch := flag.Bool("watch", false, "watch the toilet status in the command line")
flag.Parse()
if *watch {
return monitor()
}
// Instantiate the server.
srv, err := NewServer(setAddr(*addr), setCanonicalUrl(*canonicalUrl))
if err != nil {
return err
}
// Start handling signals to be able to exit cleanly.
ch := make(chan os.Signal, 1)
signal.Notify(ch, syscall.SIGINT, syscall.SIGTERM, syscall.SIGQUIT)
go func() {
<-ch
terminate(srv)
}()
// Get the sensors.
var ss []sensors.Sensor
if *rand {
ss = getRandomSensors()
} else {
var err error
ss, err = getSensors()
if err != nil {
return err
}
}
// Close the sensors on exit.
for _, sensor := range ss {
defer func(sensor sensors.Sensor) {
if err := sensor.Close(); err != nil {
log.Println("Warning:", err)
}
}(sensor)
}
// Register the sensors with the server.
for _, sensor := range ss {
if err := srv.RegisterSensor(sensor); err != nil {
terminate(srv)
return err
}
}
// Start processing requests and block until the server is terminated.
return srv.ListenAndServe()
}
func setAddr(addr string) func(*Server) {
return func(srv *Server) {
srv.SetAddr(addr)
}
}
func setCanonicalUrl(canonicalUrl string) func(*Server) {
return func(srv *Server) {
srv.SetCanonicalUrl(canonicalUrl)
}
}
func terminate(srv *Server) {
if err := srv.Terminate(); err != nil {
log.Println("Warning:", err)
}
}
func monitor() error {
// Start catching signals.
sigCh := make(chan os.Signal, 1)
signal.Notify(sigCh, syscall.SIGINT, syscall.SIGTERM, syscall.SIGQUIT)
// Get the sensors.
ss, err := getSensors()
if err != nil {
return err
}
// Close the sensors on exit.
for _, s := range ss {
defer func(s sensors.Sensor) {
if err := s.Close(); err != nil {
log.Println("Warning:", err)
}
}(s)
}
// Get the left and the right toilet sensor.
var (
left sensors.Sensor
right sensors.Sensor
)
if ss[0].Name() == toiletNameLeft {
left, right = ss[0], ss[1]
} else {
left, right = ss[1], ss[0]
}
// Print the initial status.
fmt.Println(" L | R")
fmt.Println("---|---")
fmt.Printf(" %v | %v\n", toFlag(left.State()), toFlag(right.State()))
// Start watching the sensors.
for _, s := range ss {
err := func(s sensors.Sensor) error {
return s.Watch(func() {
fmt.Printf(
" %v | %v\n", toFlag(left.State()), toFlag(right.State()))
})
}(s)
if err != nil {
return err
}
}
// Wait for a signal to arrive.
<-sigCh
return nil
}
func toFlag(state string) string {
if state == "locked" {
return "X"
}
return "O"
}