# Telego Webhook Handler Configuration: Complete Guide for Go Bots

> Configure your Telego webhook handler in Go using WebhookFastHTTP, WebhookHTTPServer, or WebhookHTTPServeMux. Receive Telegram updates efficiently via Bot.UpdatesViaWebhook for your Go bots.

- Repository: [Artem Yadelskyi/telego](https://github.com/mymmrac/telego)
- Tags: how-to-guide
- Published: 2026-03-07

---

**Telego webhook handler configuration involves registering a POST handler on your HTTP server using `WebhookFastHTTP`, `WebhookHTTPServer`, or `WebhookHTTPServeMux`, then calling `Bot.UpdatesViaWebhook` to receive Telegram updates on a Go channel.**

The [mymmrac/telego](https://github.com/mymmrac/telego) library provides a modular architecture for handling Telegram bot webhooks in Go. Instead of forcing a specific HTTP framework, it exposes adapter functions that integrate with `fasthttp`, `net/http`, or `http.ServeMux`, while managing update decoding, channel buffering, and graceful shutdown internally.

## Understanding the Telego Webhook Architecture

The webhook system separates transport concerns from update processing. The core components reside in [`webhook_handler.go`](https://github.com/mymmrac/telego/blob/main/webhook_handler.go) (server adapters) and [`webhook.go`](https://github.com/mymmrac/telego/blob/main/webhook.go) (channel management and options).

### WebhookHandler Type

The underlying handler signature is defined in [`webhook.go`](https://github.com/mymmrac/telego/blob/main/webhook.go):

```go
type WebhookHandler func(ctx context.Context, data []byte) error

```

This function receives the request context and raw JSON body. It must return an error if JSON unmarshaling fails. The `UpdatesViaWebhook` method wraps this handler to push decoded `Update` structs onto a buffered channel.

### Server Integration Helpers

Three adapter functions in [`webhook_handler.go`](https://github.com/mymmrac/telego/blob/main/webhook_handler.go) bind the `WebhookHandler` to your server:

- `WebhookFastHTTP` – wraps `*fasthttp.Server`
- `WebhookHTTPServer` – wraps `*http.Server`
- `WebhookHTTPServeMux` – registers on `*http.ServeMux`

Each helper validates the request method (POST only), checks the optional secret token via the `X-Telegram-Bot-Api-Secret-Token` header, and returns appropriate HTTP status codes (404, 405, 401, or 200).

## Configuring Webhook Handlers for Different Servers

### FastHTTP Configuration

For high-performance applications using `valyala/fasthttp`, use `WebhookFastHTTP`. The function returns a closure that accepts your `WebhookHandler`.

```go
package main

import (
	"context"
	"fmt"
	"os"

	"github.com/valyala/fasthttp"
	"github.com/mymmrac/telego"
)

func main() {
	ctx := context.Background()
	botToken := os.Getenv("TOKEN")

	bot, err := telego.NewBot(botToken, telego.WithDefaultDebugLogger())
	if err != nil {
		panic(err)
	}

	// Optional: configure webhook on Telegram servers
	_ = bot.SetWebhook(ctx, &telego.SetWebhookParams{
		URL:         "https://my.domain/bot",
		SecretToken: bot.SecretToken(),
	})

	// Initialize FastHTTP server
	fsrv := &fasthttp.Server{}

	// Configure webhook handler with 256-slot buffer
	updates, err := bot.UpdatesViaWebhook(
		ctx,
		telego.WebhookFastHTTP(fsrv, "/bot", bot.SecretToken()),
		telego.WithWebhookBuffer(256),
	)
	if err != nil {
		panic(err)
	}

	// Start server in background
	go func() { _ = fsrv.ListenAndServe(":8443") }()

	// Process updates
	for upd := range updates {
		fmt.Printf("Update %d: %+v\n", upd.UpdateID, upd)
	}
}

```

This example mirrors the official implementation in [[`examples/updates_webhook/main.go`](https://github.com/mymmrac/telego/blob/main/examples/updates_webhook/main.go)](https://github.com/mymmrac/telego/blob/main/examples/updates_webhook/main.go).

### Standard Library http.Server

For applications using `net/http`, `WebhookHTTPServer` provides identical validation logic:

```go
srv := &http.Server{Addr: ":8080"}

updates, err := bot.UpdatesViaWebhook(
    ctx,
    telego.WebhookHTTPServer(srv, "/bot", bot.SecretToken()),
    telego.WithWebhookSet(ctx, &telego.SetWebhookParams{
        URL:         "https://my.domain/bot",
        SecretToken: bot.SecretToken(),
    }),
)
if err != nil { panic(err) }

go func() { _ = srv.ListenAndServe() }()

for upd := range updates {
    // Handle update
}

```

### Using http.ServeMux

When multiplexing multiple handlers, `WebhookHTTPServeMux` registers the POST route directly:

```go
mux := http.NewServeMux()

updates, err := bot.UpdatesViaWebhook(
    ctx,
    telego.WebhookHTTPServeMux(mux, "POST /bot", bot.SecretToken()),
    telego.WithWebhookBuffer(128),
)
if err != nil { panic(err) }

go func() { _ = http.ListenAndServe(":8080", mux) }()

for upd := range updates {
    // Process update
}

```

## Processing Updates with UpdatesViaWebhook

The `Bot.UpdatesViaWebhook` method in [`webhook.go`](https://github.com/mymmrac/telego/blob/main/webhook.go) orchestrates the entire flow:

1. **State validation** – ensures no conflicting long-polling or webhook process is running (`b.run(runningWebhook)`).
2. **Option application** – applies `WebhookOption` functions to configure the internal `webhook` struct.
3. **Channel creation** – initializes a buffered `chan Update` with size determined by `WithWebhookBuffer` (default: 128).
4. **Handler registration** – invokes the provided `registerHandler` closure, supplying a `WebhookHandler` that unmarshals JSON and sends updates to the channel.
5. **Lifecycle management** – spawns a goroutine that closes the channel and clears state when the context is cancelled.

### Channel Buffering Options

Control memory usage and backpressure with `WithWebhookBuffer`:

```go
updates, err := bot.UpdatesViaWebhook(
    ctx,
    telego.WebhookFastHTTP(srv, "/bot"),
    telego.WithWebhookBuffer(64), // Small buffer for low-traffic bots
)

```

The default buffer size of 128 is defined as `defaultWebhookUpdateChanBuffer` in [`webhook.go`](https://github.com/mymmrac/telego/blob/main/webhook.go).

### Automatic Webhook Registration

Avoid manual `SetWebhook` calls by using `WithWebhookSet`:

```go
updates, err := bot.UpdatesViaWebhook(
    ctx,
    telego.WebhookHTTPServer(srv, "/bot"),
    telego.WithWebhookSet(ctx, &telego.SetWebhookParams{
        URL:            "https://api.example.com/bot",
        SecretToken:    bot.SecretToken(),
        MaxConnections: 40,
    }),
)

```

This option invokes `bot.SetWebhook` before starting the server, ensuring Telegram knows where to deliver updates.

## Summary

- **Telego webhook handler configuration** relies on adapter functions (`WebhookFastHTTP`, `WebhookHTTPServer`, `WebhookHTTPServeMux`) to bridge your HTTP server with the library's update processing.
- The `WebhookHandler` type receives raw JSON bytes and is responsible for unmarshaling and channel delivery; `UpdatesViaWebhook` orchestrates this into a buffered `<-chan Update`.
- File locations: server adapters live in [`webhook_handler.go`](https://github.com/mymmrac/telego/blob/main/webhook_handler.go), core logic in [`webhook.go`](https://github.com/mymmrac/telego/blob/main/webhook.go), and runnable examples in [`examples/updates_webhook/main.go`](https://github.com/mymmrac/telego/blob/main/examples/updates_webhook/main.go).
- Options like `WithWebhookBuffer` and `WithWebhookSet` tune performance and automate webhook registration with Telegram's API.

## Frequently Asked Questions

### How do I secure my Telego webhook endpoint?

Pass your secret token to the server adapter function (e.g., `WebhookFastHTTP(server, "/bot", bot.SecretToken())`). The handler validates the `X-Telegram-Bot-Api-Secret-Token` header against this value, returning HTTP 401 if the token mismatch indicates a forged request. You can retrieve the bot's auto-generated secret token via `bot.SecretToken()`.

### What is the difference between UpdatesViaWebhook and UpdatesViaLongPolling?

`UpdatesViaWebhook` configures the bot to receive updates via an HTTP POST endpoint that Telegram pushes to, while `UpdatesViaLongPolling` repeatedly calls the `getUpdates` method to fetch updates from Telegram's servers. The webhook approach is more efficient for high-traffic bots and provides lower latency, but requires a publicly accessible HTTPS server. `UpdatesViaWebhook` lives in [`webhook.go`](https://github.com/mymmrac/telego/blob/main/webhook.go) and uses a channel-based architecture, whereas long polling is implemented in [`long_polling.go`](https://github.com/mymmrac/telego/blob/main/long_polling.go).

### Can I use a custom HTTP server not supported by the built-in helpers?

Yes. The `UpdatesViaWebhook` method accepts any function matching `func(handler WebhookHandler) error` as the `registerHandler` parameter. Implement your own registration logic that validates the request method, verifies the secret token header, reads the body, and calls `handler(ctx, body)`. This allows integration with frameworks like Gin, Echo, or Fiber by wrapping their request contexts into the standard `WebhookHandler` signature.

### How do I handle graceful shutdown when using webhooks?

The `UpdatesViaWebhook` method accepts a `context.Context`. When this context is cancelled (e.g., via `signal.NotifyContext` on SIGINT), the library automatically closes the update channel and clears the internal `runningWebhook` state. Ensure your HTTP server also implements graceful shutdown (e.g., `http.Server.Shutdown`) to complete processing of in-flight requests before the program exits. The channel returned by `UpdatesViaWebhook` will be closed, causing any `for upd := range updates` loops to exit cleanly.