func main() {
defer mustbe.Catched(func(err error) { log.Fatalln("Fatal error:", err) })
var (
botToken string
apiHost string
dbFileName string
)
flag.StringVar(&botToken, "token", "", "telegram bot token")
flag.StringVar(&apiHost, "apihost", "freefeed.net", "backend API host")
flag.StringVar(&dbFileName, "dbfile", "", "database file name")
flag.Parse()
if botToken == "" || dbFileName == "" {
flag.Usage()
return
}
db := mustbe.OKVal(bolt.Open(dbFileName, 0600, &bolt.Options{Timeout: 1 * time.Second})).(*bolt.DB)
defer db.Close()
mustbe.OK(db.Update(func(tx *bolt.Tx) error {
mustbe.OKVal(tx.CreateBucketIfNotExists(StatesBucket))
return nil
}))
bot := mustbe.OKVal(tgbotapi.NewBotAPI(botToken)).(*tgbotapi.BotAPI)
u := tgbotapi.NewUpdate(0)
u.Timeout = 60
updates, err := bot.GetUpdatesChan(u)
if err != nil {
log.Fatalln("Can not get update chan:", err)
return
}
log.Println("Starting bot", bot.Self.UserName)
app := &App{
db: db,
apiHost: apiHost,
outbox: make(chan tgbotapi.Chattable, 0),
rts: make(map[int]*Realtime),
cache: gcache.New(1000).ARC().Build(),
}
app.LoadRT()
for {
select {
case update := <-updates:
go app.HandleMessage(&update.Message)
case msg := <-app.outbox:
bot.Send(msg)
}
}
}
func ExampleOKVal() {
defer mustbe.Catched(func(err error) {
fmt.Println("Catched", err)
})
divide := func(x, y int) (int, error) {
if y == 0 {
return 0, errors.New("division by zero")
}
return x / y, nil
}
fmt.Println("4 / 2 =", mustbe.OKVal(divide(4, 2)).(int))
fmt.Println("4 / 0 =", mustbe.OKVal(divide(4, 0)).(int)) // will not be printed
// Output: 4 / 2 = 2
// Catched division by zero
}
func (a *App) Handler(w http.ResponseWriter, r *http.Request) {
defer mustbe.Catched(func(err error) {
w.Header().Set("Content-Type", "application/json")
w.WriteHeader(http.StatusBadRequest)
json.NewEncoder(w).Encode(H{"err": err.Error(), "from": "aprx"})
})
// request path: /frf-domain/api-path
pp := strings.SplitN(r.URL.Path, "/", 3)[1:]
mustbeTrue(len(pp) == 2, "Invalid request path")
domain, path := pp[0], "/"+pp[1]
domainFound := false
for _, d := range a.FRFDomains {
if d == domain {
domainFound = true
break
}
}
mustbeTrue(domainFound, "Invalid frf domain")
var (
accessToken string
frfRequestBody []byte
)
switch r.Header.Get("Content-Type") {
case "application/x-www-form-urlencoded":
r.ParseForm()
accessToken = r.PostForm.Get("accessToken")
r.PostForm.Del("accessToken")
frfRequestBody = []byte(r.PostForm.Encode())
case "application/json", "application/json; charset=utf-8":
h := make(H)
mustbe.OK(json.NewDecoder(r.Body).Decode(h))
accessToken = h["accessToken"].(string)
delete(h, "accessToken")
frfRequestBody = mustbe.OKVal(json.Marshal(h)).([]byte)
}
req, err := http.NewRequest(
r.Method,
"https://"+domain+path,
bytes.NewReader(frfRequestBody),
)
mustbe.OK(err)
for _, h := range HeadersFromClient {
if hh, ok := r.Header[h]; ok {
req.Header[h] = hh
}
}
if accessToken != "" {
req.Header.Set("X-Authentication-Token", accessToken)
}
resp, err := http.DefaultClient.Do(req)
mustbe.OK(err)
defer resp.Body.Close()
for _, h := range HeadersFromBackend {
if hh, ok := resp.Header[h]; ok {
w.Header()[h] = hh
}
}
w.WriteHeader(resp.StatusCode)
io.Copy(w, resp.Body)
}