# Telebot >"I never knew creating Telegram bots could be so _sexy_!" [![GoDoc](https://godoc.org/gopkg.in/tucnak/telebot.v2?status.svg)](https://godoc.org/gopkg.in/tucnak/telebot.v2) [![Travis](https://travis-ci.org/tucnak/telebot.svg?branch=v2)](https://travis-ci.org/tucnak/telebot) ```bash go get -u gopkg.in/tucnak/telebot.v2 ``` * [Overview](#overview) * [Getting Started](#getting-started) - [Poller](#poller) - [Commands](#commands) - [Files](#files) - [Sendable](#sendable) - [Editable](#editable) - [Keyboards](#keyboards) - [Inline mode](#inline-mode) * [Contributing](#contributing) * [Donate](#donate) * [License](#license) # Overview Telebot is a bot framework for [Telegram](https://telegram.org) [Bot API](https://core.telegram.org/bots/api). This package provides the best of its kind API for command routing, inline query requests and keyboards, as well as callbacks. Actually, I went a couple steps further, so instead of making a 1:1 API wrapper I chose to focus on the beauty of API and performance. Some of the strong sides of telebot are: * Real concise API * Command routing * Middleware * Transparent File API * Effortless bot callbacks All the methods of telebot API are _extremely_ easy to memorize and get used to. Also, consider Telebot a highload-ready solution. I'll test and benchmark the most popular actions and if necessary, optimize against them without sacrificing API quality. # Getting Started Let's take a look at the minimal telebot setup: ```go package main import ( "time" tb "gopkg.in/tucnak/telebot.v2" ) func main() { b, err := tb.NewBot(tb.Settings{ Token: "TOKEN_HERE", Poller: &tb.LongPoller{Timeout: 10 * time.Second}, }) if err != nil { log.Fatal(err) return } b.Handle("/hello", func(m *tb.Message) { b.Send(m.Sender, "hello world") }) b.Start() } ``` Simple, innit? Telebot's routing system takes care of deliviering updates to their endpoints, so in order to get to handle any meaningful event, all you got to do is just plug your function to one of the Telebot-provided endpoints. You can find the full list [here](https://godoc.org/gopkg.in/tucnak/telebot.v2#pkg-constants). ```go b, _ := tb.NewBot(settings) b.Handle(tb.OnText, func(m *tb.Message) { // all the text messages that weren't // captured by existing handlers } b.Handle(tb.OnPhoto, func(m *tb.Message) { // photos only } b.Handle(tb.OnChannelPost, func (m *tb.Message) { // channel posts only }) b.Handle(tb.Query, func (q *tb.Query) { // incoming inline queries }) ``` Now there's a dozen of supported endpoints (see package consts). Let me know if you'd like to see some endpoint or endpoint idea implemented. This system is completely extensible, so I can introduce them without braking backwards-compatibity. ## Poller Telebot doesn't really care how you provide it with incoming updates, as long as you set it up with a Poller: ```go // Poller is a provider of Updates. // // All pollers must implement Poll(), which accepts bot // pointer and subscription channel and start polling // synchronously straight away. type Poller interface { // Poll is supposed to take the bot object // subscription channel and start polling // for Updates immediately. // // Poller must listen for stop constantly and close // it as soon as it's done polling. Poll(b *Bot, updates chan Update, stop chan struct{}) } ``` Telegram Bot API supports long polling and webhook integration. I don't really care about webhooks, so the only concrete Poller you'll find in the library is the `LongPoller`. Poller means you can plug telebot into whatever existing bot infrastructure (load balancers?) you need, if you need to. Another great thing about pollers is that you can chain them, making some sort of middleware: ```go poller := &tb.LongPoller{Timeout: 15 * time.Second} spamProtected := tb.NewMiddlewarePoller(poller, func(upd *tb.Update) bool { if upd.Message == nil { return true } if strings.Contains(upd.Message.Text, "spam") { return false } return true }) bot, _ := tb.NewBot(tb.Settings{ // ... Poller: spamProtected, }) // graceful shutdown go func() { <-time.After(N * time.Second) bot.Stop() })() bot.Start() // blocks until shutdown fmt.Println(poller.LastUpdateID) // 134237 ``` ## Commands When handling commands, Telebot supports both direct (`/command`) and group-like syntax (`/command@botname`) and will never deliver messages addressed to some other bot, even if [privacy mode](https://core.telegram.org/bots#privacy-mode) is off. For simplified deep-linking, telebot also extracts payload: ```go // Command: /start b.Handle("/start", func(m *tb.Message) { if !m.Private() { return } fmt.Println(m.Payload) // }) ``` ## Files >Telegram allows files up to 20 MB in size. Telebot allows to both upload (from disk / by URL) and download (from Telegram) and files in bot's scope. Also, sending any kind of media with a File created from disk will upload the file to Telegram automatically: ```go a := &tb.Audio{File: tb.FromDisk("file.ogg")} fmt.Println(a.OnDisk()) // true fmt.Println(a.InCloud()) // false // Will upload the file from disk and send it to recipient bot.Send(recipient, a) // Next time you'll be sending this very *Audio, Telebot won't // re-upload the same file but rather utilize its Telegram FileID bot.Send(otherRecipient, a) fmt.Println(a.OnDisk()) // true fmt.Println(a.InCloud()) // true fmt.Println(a.FileID) // ``` You might want to save certain `File`s in order to avoid re-uploading. Feel free to marshal them into whatever format, `File` only contain public fields, so no data will ever be lost. ## Sendable Send is undoubteldy the most important method in Telebot. `Send()` accepts a `Recipient` (could be user, group or a channel) and a `Sendable`. FYI, not only all telebot-provided media types (`Photo`, `Audio`, `Video`, etc.) are `Sendable`, but you can create composite types of your own. As long as they satisfy `Sendable`, Telebot will be able to send them out. ```go // Sendable is any object that can send itself. // // This is pretty cool, since it lets bots implement // custom Sendables for complex kind of media or // chat objects spanning across multiple messages. type Sendable interface { Send(*Bot, Recipient, *SendOptions) (*Message, error) } ``` The only type at the time that doesn't fit `Send()` is `Album` and there is a reason for that. Albums were added not so long ago, so they are slightly quirky for backwards compatibilities sake. In fact, an `Album` can be sent, but never received. Instead, Telegram returns a `[]Message`, one for each media object in the album: ```go p := &tb.Photo{File: tb.FromDisk("chicken.jpg")} v := &tb.Video{File: tb.FromURL("http://video.mp4")} msgs, err := b.SendAlbum(user, tb.Album{p, v}) ``` ### Send options Send options are objects and flags you can pass to `Send()`, `Edit()` and friends as optional arguments (following the recipient and the text/media). The most important one is called `SendOptions`, it lets you control _all_ the properties of the message supported by Telegram. The only drawback is that it's rather inconvenient to use at times, so `Send()` supports multiple shorthands: ```go // regular send options b.Send(user, "text", &tb.SendOptions{ // ... }) // ReplyMarkup is a part of SendOptions, // but often it's the only option you need b.Send(user, "text", &tb.ReplyMarkup{ // ... }) // flags: no notification && no web link preview b.Send(user, "text", tb.Silent, tb.NoPreview) ``` Full list of supported option-flags you can find [here](https://github.com/tucnak/telebot/blob/v2/options.go#L9). ## Editable If you want to edit some existing message, you don't really need to store the original `*Message` object. In fact, upon edit, Telegram only requires two IDs: ChatID and MessageID. And it doesn't really require the whole Message. Also you might want to store references to certain messages in the database, so for me it made sense for *any* Go struct to be editable as Telegram message, to implement Editable interface: ```go // Editable is an interface for all objects that // provide "message signature", a pair of 32-bit // message ID and 64-bit chat ID, both required // for edit operations. // // Use case: DB model struct for messages to-be // edited with, say two collums: msg_id,chat_id // could easily implement MessageSig() making // instances of stored messages editable. type Editable interface { // MessageSig is a "message signature". // // For inline messages, return chatID = 0. MessageSig() (messageID int, chatID int64) } ``` For example, `Message` type is Editable. Here is an implementation of `StoredMessage` type, provided by telebot: ```go // StoredMessage is an example struct suitable for being // stored in the database as-is or being embedded into // a larger struct, which is often the case (you might // want to store some metadata alongside, or might not.) type StoredMessage struct { MessageID int `sql:"message_id" json:"message_id"` ChatID int64 `sql:"chat_id" json:"chat_id"` } func (x StoredMessage) MessageSig() (int, int64) { return x.MessageID, x.ChatID } ``` Why bother at all? Well, it allows you to do things like this: ```go // just two integer columns in the database var msgs []tb.StoredMessage db.Find(&msgs) // gorm syntax for _, msg := range msgs { bot.Edit(&msg, "Updated text.") // or bot.Delete(&msg) } ``` I find it incredibly neat. Worth noting, at this point of time there exists another method in the Edit family, `EditCaption()` which is of a pretty rare use, so I didn't bother including it to `Edit()`, just like I did with `SendAlbum()` as it would inevitably lead to unnecessary complications. ```go var m *Message // change caption of a photo, audio, etc. bot.EditCaption(m, "new caption") ``` ## Keyboards Telebot supports both kinds of keyboards Telegram provides: reply and inline keyboards. All buttons can act as endpoints for `Handle()`: `Handle()`: ```go func main() { b, _ := tb.NewBot(tb.Settings{...}) // This button will be displayed in user's // reply keyboard. replyBtn := tb.ReplyButton{Text: "🌕 Button #1"} replyKeys := [][]tb.ReplyButton{ []tb.ReplyButton{replyBtn}, // ... } // And this one — just under the message itself. // Pressing it will cause the client to send // the bot a callback. // // Make sure Unique stays unique as it has to be // for callback routing to work. inlineBtn := tb.InlineButton{ Unique: "sad_moon", Text: "🌚 Button #2", } inlineKeys := [][]tb.InlineButton{ []tb.InlineButton{inlineBtn}, // ... } b.Handle(&replyBtn, func(m *tb.Message) { // on reply button pressed }) b.Handle(&inlineBtn, func(c *tb.Callback) { // on inline button pressed (callback!) // always respond! c.Respond(&tb.CallbackResponse{...}) }) // Command: /start b.Handle("/start", func(m *tb.Message) { if !m.Private() { return } b.Send(m.Sender, "Hello!", &tb.ReplyMarkup{ ReplyKeyboard: replyKeys, InlineKeyboard: inlineKeys, }) }) b.Start() } ``` ## Inline mode So if you want to handle incoming inline queries you better plug the `tb.OnQuery` endpoint and then use the `Answer()` method to send a list of inline queries back. I think at the time of writing, telebot supports all of the provided result types (but not the cached ones). This is how it looks like: ```go b.Handle(tb.OnQuery, func(q *tb.Query) { urls := []string{ "http://photo.jpg", "http://photo2.jpg", } results := make(tb.Results, len(urls)) // []tb.Result for i, url := range urls { result := &tb.PhotoResult{ URL: url, // required for photos ThumbURL: url, } results[i] = result } err := b.Answer(q, &tb.QueryResponse{ Results: results, CacheTime: 60, // a minute }) if err != nil { fmt.Println(err) } }) ``` There's not much to talk about really. It also support some form of authentication through deep-linking. For that, use fields `SwitchPMText` and `SwitchPMParameter` of `QueryResponse`. # Contributing 1. Fork it 2. Clone it: `git clone https://github.com/tucnak/telebot` 3. Create your feature branch: `git checkout -b my-new-feature` 4. Make changes and add them: `git add .` 5. Commit: `git commit -m 'Add some feature'` 6. Push: `git push origin my-new-feature` 7. Pull request # Donate I do coding for fun but I also try to search for interesting solutions and optimize them as much as possible. If you feel like it's a good piece of software, I wouldn't mind a tip! Bitcoin: `1DkfrFvSRqgBnBuxv9BzAz83dqur5zrdTH` # License Telebot is distributed under MIT.