gotelegram

README

Build Telegram bots in Go that just work.
Type-safe. Batteries included. Always up to date with the latest Bot API.

Bot API v10.0 · 176 methods · 301 types · 1428 auto-generated tests

Website · API Reference · Examples · pkg.go.dev

---

Hello, Telegram 👋

bot := client.New(os.Getenv("TELEGRAM_BOT_TOKEN"))
router := dispatch.New(bot)

router.OnCommand("/start", func(c *dispatch.Context, m *api.Message) error {
    _, err := api.SendMessage(c.Ctx, c.Bot, &api.SendMessageParams{
        ChatID: api.ChatIDFromInt(m.Chat.ID),
        Text:   "Hi " + m.From.FirstName + "! 👋",
    })
    return err
})

router.Run(ctx, transport.NewLongPoller(bot))

That's a working bot. No magic strings, no any, no guessing what fields exist — your editor autocompletes everything.

Why you'll like it

• 🎯 No any, anywhere. Telegram's "Integer or String" and "one of N types" unions are real Go types you can switch on.
• 🔋 Batteries included. Long-poll, webhooks, retries on rate limits, conversation state machines, filters, handler groups — out of the box.
• 🔄 Always current. The whole API is generated from Telegram's live docs. New Bot API release? make regen and you're done.
• 🪶 Pluggable everything. Swap the HTTP client, JSON codec, or storage backend with a one-method interface. No forks.
• 🧪 Already tested. 1428 generated tests cover every method × every failure mode (success, API errors, network failures, parse errors, timeouts, missing fields, forbidden, server errors).

Install

go get github.com/lukaszraczylo/go-telegram

A complete echo bot

Long-poll, graceful shutdown, retries on Telegram's 429 retry_after:

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)
    router.OnCommand("/start", func(c *dispatch.Context, m *api.Message) error {
        _, err := api.SendMessage(c.Ctx, c.Bot, &api.SendMessageParams{
            ChatID: api.ChatIDFromInt(m.Chat.ID),
            Text:   fmt.Sprintf("Hello %s! Send me anything.", m.From.FirstName),
        })
        return err
    })
    router.OnText(`.+`, func(c *dispatch.Context, m *api.Message) error {
        _, err := api.SendMessage(c.Ctx, c.Bot, &api.SendMessageParams{
            ChatID:          api.ChatIDFromInt(m.Chat.ID),
            Text:            m.Text,
            ReplyParameters: &api.ReplyParameters{MessageID: m.MessageID},
        })
        return err
    })

    if err := router.Run(ctx, transport.NewLongPoller(bot)); err != nil && err != context.Canceled {
        log.Printf("router exited: %v", err)
    }
}

Examples

Run any example: TELEGRAM_BOT_TOKEN=xxx go run ./examples/<name>

Category	Example	What it shows
Basics	echo	Long-poll echo bot
	webhook	Webhook server with secret-token verification
	files	Upload and download cycle
	inline	Inline-mode results
Conversations & state	conversation	Multi-step state machine with /cancel exit
	stateful	Per-user state via closures
	callback	Inline keyboards and callback query handling
	pagination	Multi-page inline keyboard
Group management	welcome	Greet new chat members
	moderation	Kick/ban/mute/warn with permission checks
	admin	Auth middleware allowlist
Advanced	middleware	Use chains
	polls	sendPoll and answer tally
	payments	Invoice → pre-checkout → success

Optional fields

Telegram marks many fields as optional. For optional scalars (int, bool, float) we use pointers so you can explicitly send false or 0 when the wire format needs to override a chat default. The api.Ptr helper keeps that ergonomic:

api.SendMessage(ctx, bot, &api.SendMessageParams{
    ChatID:              api.ChatIDFromInt(chatID),
    Text:                "hi",
    DisableNotification: api.Ptr(true),     // type inferred
})

api.GetUserProfilePhotos(ctx, bot, &api.GetUserProfilePhotosParams{
    UserID: userID,
    Limit:  api.Ptr[int64](5),              // explicit type for untyped literals
})

Optional structs and slices are already nullable in Go — no helper needed.

Reference docs

Full API reference is auto-generated from source comments and lives in docs/reference/ — browse package by package on GitHub, or read it rendered at go-telegram.raczylo.com and pkg.go.dev.

How it works

Bot client and pluggable transport

client.New accepts functional options:

bot := client.New(token,
    client.WithHTTPClient(doer),       // any HTTPDoer (one-method interface)
    client.WithCodec(myCodec),         // any Codec (Marshal + Unmarshal)
    client.WithLogger(myLogger),
    client.WithBaseURL("https://..."), // proxy or local Bot API server
)

HTTPDoer is Do(*http.Request) (*http.Response, error) — a plain *http.Client satisfies it. Codec is Marshal(any) ([]byte, error) + Unmarshal([]byte, any) error — the default wraps goccy/go-json.

Every API call goes through client.Call[Req, Resp]; per-method generated functions are thin wrappers.

Typed unions — no any

Telegram's docs describe many fields as "Integer or String" or "one of N types". go-telegram turns every one of these into a concrete Go type.

// ChatID: construct from int64 or @username
chatID := api.ChatIDFromInt(123456789)
chatID := api.ChatIDFromString("@mychannel")

// Discriminated unions — 13 interfaces with auto-decode via generated UnmarshalJSON
for _, u := range updates {
    if u.MyChatMember == nil {
        continue
    }
    switch v := u.MyChatMember.OldChatMember.(type) {
    case *api.ChatMemberOwner:
        log.Println("was owner")
    case *api.ChatMemberAdministrator:
        log.Printf("was admin: can_post=%v", v.CanPostMessages)
    }
}

Full union list: ChatMember, MessageOrigin, ReactionType, PaidMedia, BackgroundType, BackgroundFill, ChatBoostSource, RevenueWithdrawalState, TransactionPartner, MenuButton, OwnedGift, StoryAreaType, MaybeInaccessibleMessage, plus ChatID, MessageOrBool, and InputFile.

Dispatcher, filters, and conversations

The router dispatches each update in its own goroutine (semaphore-bounded, default 50):

r := dispatch.New(bot, dispatch.WithMaxConcurrency(50))

r.OnCommand("/start", handler)
r.OnText(`^hi (\w+)`, handler)
r.OnCallback(`^like:\d+`, handler)
r.OnInlineQuery(handler)
r.OnMyChatMember(handler)
// + 20 more typed On* methods

Composable filters — each update type has its own filter package:

import "github.com/lukaszraczylo/go-telegram/dispatch/filters/message"

r.OnMessageFilter(
    message.Command("/admin").And(message.IsReply()),
    handler,
)

Filter packages: message, callback, inline, chatmember, chatjoinrequest, precheckoutquery. Combinators: And, Or, Not, All, Any.

Conversation state machines — multi-step flows with pluggable storage:

conv := &conversation.Conversation{
    EntryPoints: []conversation.Step{{
        Filter: dispatch.FilterFunc(func(c *dispatch.Context, u *api.Update) bool {
            return u.Message != nil && u.Message.Text == "/start"
        }),
        Handler: func(c *dispatch.Context, u *api.Update) error {
            // send prompt, advance state
            return conversation.Next("await_name")
        },
    }},
    States: map[conversation.State][]conversation.Step{
        "await_name": {{
            Handler: func(c *dispatch.Context, u *api.Update) error {
                return conversation.End()
            },
        }},
    },
}
router.Use(conv.Dispatch)

Key strategies: KeyByUser, KeyByChat, KeyByUserAndChat (default). Default storage: MemoryStorage (in-process, concurrency-safe). Implement the Storage interface for Redis or any other backend.

Errors and retry middleware

Wrap the default HTTP doer with RetryDoer for production:

bot := client.New(token,
    client.WithHTTPClient(
        client.NewRetryDoer(
            client.NewDefaultHTTPDoer(),
            client.WithMaxAttempts(5),
            client.WithBaseBackoff(500*time.Millisecond),
        ),
    ),
)

RetryDoer retries on 429, 5xx, and transient network errors. On a 429 it reads retry_after from Telegram's response body and waits exactly that long — overriding any backoff calculation. Request bodies are buffered and replayed across attempts.

Sentinel errors for errors.Is checks: client.ErrForbidden, client.ErrNotFound, client.ErrUnauthorized.

Handler groups and named handlers

Priority-ordered groups with flow control signals:

// Group 0 runs first — return EndGroups to stop, ContinueGroups to continue
r.Group(0).OnText(`.*`, authMiddleware)
r.Group(1).OnText(`.*`, businessHandler)

Named handlers — register and replace at runtime:

named := dispatch.NewNamedHandlers[*api.Message]()
named.Set("main", myHandler)
r.OnCommand("/cmd", named.Handler())
// later: named.Set("main", updatedHandler)

Keeping up with Telegram

When Telegram ships a new Bot API version, regenerating the whole library is one command:

make snapshot   # grab the latest HTML from core.telegram.org
make regen      # scrape → audit → emit Go → run tests → regenerate docs

The audit tool checks for any-typed escapes, surprise bool returns, and signature drift. CI runs it on every PR, and a weekly workflow opens an auto-PR with regenerated code so a new Bot API version never sits longer than a week.

If something in Telegram's docs trips up the scraper, add an override to internal/spec/overrides.json. The audit will tell you what to put there.

Testing

Mock the one-method HTTPDoer interface to test handlers in isolation — no test server needed:

type fakeDoer struct{ body string }
func (f fakeDoer) Do(*http.Request) (*http.Response, error) {
    return &http.Response{
        StatusCode: 200,
        Body:       io.NopCloser(strings.NewReader(f.body)),
    }, nil
}

bot := client.New("token", client.WithHTTPClient(fakeDoer{
    body: `{"ok":true,"result":{"message_id":1,"date":0,"chat":{"id":1,"type":"private"}}}`,
}))

The library's own generated test suite (api/methods_gen_test.go) covers 176 methods × 8 scenarios each: Success, APIError, NetworkError, ParseError, ContextCanceled, MissingRequiredFields, Forbidden, ServerError.

Contributing

See CONTRIBUTING.md.

License

MIT

Documentation

Overview

Package gotelegram is the module root.

The public API lives in the api, client, transport, and dispatch packages. See https://github.com/lukaszraczylo/go-telegram for documentation.