The result type of [GetMe (and getMe extension)](https://github.com/InsanusMokrassar/TelegramBotAPI/blob/master/TelegramBotAPI/src/commonMain/kotlin/com/github/insanusmokrassar/TelegramBotAPI/requests/GetMe.kt)
By default, for JVM there is implemented `CIO` client engine, but there is not server engine. Both can be changed like
here:
```groovy
dependencies {
// ...
implementation "io.ktor:ktor-server-cio:$ktor_version" // for implementing of server engine
implementation "io.ktor:ktor-client-okhttp:$ktor_version" // for implementing of additional client engine
// ...
}
```
You can avoid using of `server` dependency in case if you will not use `Webhook`s. In this case,
dependencies list will be simplify:
```groovy
dependencies {
// ...
implementation "io.ktor:ktor-client-okhttp:$ktor_version" // for implementing of additional client engine
// ...
}
```
Here was used `okhttp` realisation of client, but there are several others engines for Ktor. More information
available on ktor.io site for [client](https://ktor.io/clients/http-client/engines.html) and [server](https://ktor.io/quickstart/artifacts.html)
engines.
## Getting updates
In this library currently realised two ways to get updates from telegram:
* Polling - in this case bot will request updates from time to time (you can set up delay between requests)
* Webhook via reverse proxy or something like this
### Updates filters
Currently webhook method contains `UpdatesFilter` as necessary argument for getting updates.
`UpdatesFilter` will sort updates and throw their into different callbacks. Currently supporting
separate getting updates for media groups - they are accumulating with debounce in one second
(for being sure that all objects of media group was received).
Updates polling also support `UpdatesFilter` but it is not required to use it and you can get updates directly
in `UpdateReceiver`, which you will provide to `startGettingOfUpdates` method
### Webhook set up
If you wish to use webhook method, you will need:
* White IP - your IP address or host, which available for calling. [TelegramBotAPI](https://core.telegram.org/bots/api#setwebhook)
recommend to use some unique address for each bot which you are using
* SSL certificate. Usually you can obtain the certificate using your domain provider, [Let'sEncrypt](https://letsencrypt.org/) or [create it](https://core.telegram.org/bots/self-signed)
* Nginx or something like this
Template for Nginx server config you can find in [this gist](https://gist.github.com/InsanusMokrassar/fcc6e09cebd07e46e8f0fdec234750c4#file-nginxssl-conf).
For webhook you can provide `File` with public part of certificate, `URL` where bot will be available and inner `PORT` which
will be used to start receiving of updates. Actually, you can skip passing of `File` when you have something like
nginx for proxy forwarding.
In case of using `nginx` with reverse-proxy config, setting up of Webhook will look like:
```kotlin
requestsExecutor.setWebhook(
WEBHOOK_URL,
INTERNAL_PORT,
filter,
ENGINE_FACTORY
)
```
Here:
*`WEBHOOK_URL` - the url which will be used by Telegram system to send updates
*`INTERNAL_PORT` - the port which will be used in bot for listening of updates
*`filter` - instance of [UpdatesFilter](https://github.com/InsanusMokrassar/TelegramBotAPI/blob/master/TelegramBotAPI/src/commonMain/kotlin/com/github/insanusmokrassar/TelegramBotAPI/updateshandlers/UpdatesFilter.kt),
which will be used to filter incoming updates
*`ENGINE_FACTORY` - used factory name, for example, `CIO` in case of usage `io.ktor:ktor-server-cio` as server engine
