Files
go-telegram/examples/welcome/main.go
T
lukaszraczylo ac7cae8fa7 Initial release of go-telegram
A fully-generated, strongly-typed Go client for the Telegram Bot API.

* 176 methods + 301 types generated from Bot API v10.0
* 1408 auto-generated tests (8 scenarios per method)
* Typed unions throughout — no 'any' in the public surface
* Pluggable HTTP transport and JSON codec (default goccy/go-json)
* Built-in retry middleware honouring Telegram's retry_after
* Generic dispatcher with filters and conversation handlers
* Self-verifying codegen pipeline (regen → audit → emit → run tests)
* 14 example bots covering common patterns
2026-05-09 13:09:27 +01:00

83 lines
2.3 KiB
Go

// Package main demonstrates greeting new chat members and detecting leaves.
//
// The bot must be an admin in the group with "can read messages" (or at least
// be able to receive service messages) to get new-member and left-member events.
//
// TELEGRAM_BOT_TOKEN=xxx go run ./examples/welcome
package main
import (
"context"
"fmt"
"log"
"os"
"os/signal"
"syscall"
"github.com/lukaszraczylo/go-telegram/api"
"github.com/lukaszraczylo/go-telegram/client"
"github.com/lukaszraczylo/go-telegram/dispatch"
"github.com/lukaszraczylo/go-telegram/transport"
)
func main() {
token := os.Getenv("TELEGRAM_BOT_TOKEN")
if token == "" {
log.Fatal("TELEGRAM_BOT_TOKEN required")
}
ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
defer stop()
bot := client.New(token,
client.WithHTTPClient(client.NewRetryDoer(client.NewDefaultHTTPDoer())),
)
router := dispatch.New(bot)
// Greet every new member that joins the group.
router.OnMessageFilter(
func(m *api.Message) bool { return len(m.NewChatMembers) > 0 },
func(c *dispatch.Context, m *api.Message) error {
for _, u := range m.NewChatMembers {
name := u.FirstName
if u.LastName != "" {
name += " " + u.LastName
}
_, err := api.SendMessage(c.Ctx, c.Bot, &api.SendMessageParams{
ChatID: api.ChatIDFromInt(m.Chat.ID),
Text: fmt.Sprintf("Welcome, %s! Please read the pinned rules before posting.", name),
})
if err != nil {
log.Printf("send welcome: %v", err)
}
}
return nil
},
)
// Log when a member leaves (or is removed from) the group.
router.OnMessageFilter(
func(m *api.Message) bool { return m.LeftChatMember != nil },
func(c *dispatch.Context, m *api.Message) error {
log.Printf("user %d (%s) left chat %d",
m.LeftChatMember.ID,
m.LeftChatMember.FirstName,
m.Chat.ID,
)
return nil
},
)
// Detect when the bot itself is added to a group.
router.OnMyChatMember(func(c *dispatch.Context, u *api.ChatMemberUpdated) error {
log.Printf("bot chat membership changed in %d: new status = %T", u.Chat.ID, u.NewChatMember)
return nil
})
poller := transport.NewLongPoller(bot)
if err := router.Run(ctx, poller); err != nil && err != context.Canceled {
log.Printf("router exited: %v", err)
}
}