Updates receiving

Long polling

Long polling is used by default. You don't need any movement to make the bot work.

It can be configured easy:

val config = TelegramBotConfig().apply {
    receiving {
        longPolling {
            limit = 10 // default null
            timeout = 25 // default 30
            retryDelay = 5_000 // default 5,000
            // default CoroutineScope(Dispatchers.Default + SupervisorJob() + CoroutineName("TelegramBot"))
            scope = CoroutineScope(Dispatchers.Default.limitedParallelism(10) + SupervisorJob())
        }
    }
}

That`s all. Bot works.

Webhook

Now available only for Spring. *But don't get too upset. More details in "Custom receiver".

It can be configured easy too:

telegram-bot:
  spring:
    update-receiver: webhook
    # URL to your bot application
    update-receiver.webhook.url.host: "https://my.domain.com/api/my-awesome-bot"

By default, unique random token will be generated for X-Telegram-Bot-Api-Secret-Token header. By default, full URL will be concatenated to https://my.domain.com/api/my-awesome-bot/updates/receive.

All available properties:

PROPERTY	DEFAULT	DESCRIPTION
`telegram-bot.spring.update-receiver`	`long-polling`	Choosing long polling or webhook.
`telegram-bot.spring.update-receiver.webhook.url.host`	-	`Required` URL directly to your application. Will be concatenated with `urlPath`.
`telegram-bot.spring.update-receiver.webhook.url.path`	`/updates/receive`	API mapping in application. Will be concatenated with `urlHost`.
`telegram-bot.spring.update-receiver.webhook.certificate.path`	-	Path to certificate in resources. For example, `/sert.pem`.
`telegram-bot.spring.update-receiver.webhook.ip-address`	-	The fixed IP address instead of the IP address resolved through DNS.
`telegram-bot.spring.update-receiver.webhook.max-connections`	-	The maximum allowed number of simultaneous HTTPS connections.
`telegram-bot.spring.update-receiver.webhook.drop-pending-updates`	-	Pass True to drop all pending updates.
`telegram-bot.spring.update-receiver.webhook.secret-token`	-	A secret token to be sent in a header `X-Telegram-Bot-Api-Secret-Token`.
`telegram-bot.spring.update-receiver.webhook.secret-token.random-generation`	`RANDOM_UUID`	Autogeneration of secret token. Available `NONE`, `RANDOM_UUID`, `RANDOM_256_CHARS`.
`telegram-bot.spring.update-receiver.webhook.secret-token.random-generation.print-on-startup`	`false`	Pass True to print generated token on application startup.

More info about webhook in official docs.

Custom receiver

And you can implement custom receiver (long polling or webhook, whatever you want).

class CustomUpdateReceiver(
    private val bot: TelegramBot,
    private val updateResolver: UpdateResolver,
    private val config: CustomConfig,
) : UpdateReceiver {

    private val logger: Logger = LoggerFactory.getLogger(CustomUpdateReceiver::class.java)

    override fun start(): Unit = runBlocking(Dispatchers.Default) {
        // Starting your bot
        // Calling bot.getUpdates() or bot.setWebhook()
        logger.info("Started custom update receiver.")
    }
    
    // Calling updateResolver.processUpdate()

    override fun stop(): Unit = runBlocking(Dispatchers.Default) {
        // Stopping your bot
        // Calling bot.deleteWebhook() or stopping client with long polling
        logger.info("Stopped custom update receiver.")
    }
}

val config = TelegramBotConfig().apply {
    // other settings

    receiving {
        updateReceiver = { CustomUpdateReceiver(telegramBot, receiving.updateResolver, CustomConfig()) }
    }
}

You can find examples in LongPollingUpdateReceiver and WebhookUpdateReceiver.

Last modified: 27 July 2024