Add Bot API 10.2 Communities support example

New CommunitiesBot demonstrating the 36.0.0 communities API:
- onCommunityChatAdded / onCommunityChatRemoved triggers for the
  community_chat_added / community_chat_removed service events
- reading the Community (id/name) from CommunityChatAdded
- ExtendedChat.community (ChatFullInfo.community) via getChat
- waitCommunityChatAdded expectation

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

CommunitiesBot/README.md

@@ -0,0 +1,12 @@
+# CommunitiesBot
+
+Demonstrates Communities support introduced in Telegram Bot API 10.2.
+
+Add the bot to a chat that belongs to a community. It reports when the chat is added to or removed from a
+community, and `/community` prints the chat's current community (read from `getChat().community`).
+
+## Launch
+
+```bash
+../gradlew :CommunitiesBot:run --args="BOT_TOKEN"
+```

CommunitiesBot/build.gradle

@@ -0,0 +1,21 @@
+buildscript {
+    repositories {
+        mavenCentral()
+    }
+
+    dependencies {
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+    }
+}
+
+apply plugin: 'kotlin'
+apply plugin: 'application'
+
+mainClassName="CommunitiesBotKt"
+
+
+dependencies {
+    implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
+
+    implementation "dev.inmo:tgbotapi:$telegram_bot_api_version"
+}

CommunitiesBot/src/main/kotlin/CommunitiesBot.kt

@@ -0,0 +1,98 @@
+import dev.inmo.kslog.common.KSLog
+import dev.inmo.kslog.common.LogLevel
+import dev.inmo.kslog.common.defaultMessageFormatter
+import dev.inmo.kslog.common.setDefaultKSLog
+import dev.inmo.micro_utils.coroutines.subscribeSafelyWithoutExceptions
+import dev.inmo.tgbotapi.extensions.api.bot.getMe
+import dev.inmo.tgbotapi.extensions.api.chat.get.getChat
+import dev.inmo.tgbotapi.extensions.api.send.reply
+import dev.inmo.tgbotapi.extensions.api.send.send
+import dev.inmo.tgbotapi.extensions.behaviour_builder.expectations.waitCommunityChatAdded
+import dev.inmo.tgbotapi.extensions.behaviour_builder.telegramBotWithBehaviourAndLongPolling
+import dev.inmo.tgbotapi.extensions.behaviour_builder.triggers_handling.onCommand
+import dev.inmo.tgbotapi.extensions.behaviour_builder.triggers_handling.onCommunityChatAdded
+import dev.inmo.tgbotapi.extensions.behaviour_builder.triggers_handling.onCommunityChatRemoved
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.flow.first
+
+/**
+ * This bot demonstrates Communities support introduced in Telegram Bot API 10.2.
+ *
+ * A community groups several chats together. When a chat is added to (or removed from) a community, the bot
+ * receives a service event in that chat.
+ *
+ * Key concepts demonstrated:
+ * - [onCommunityChatAdded] — trigger for the `community_chat_added` service event. The handler receives a
+ *   [dev.inmo.tgbotapi.types.message.abstracts.ChatEventMessage] carrying a
+ *   [dev.inmo.tgbotapi.types.communities.CommunityChatAdded] whose `community` is the
+ *   [dev.inmo.tgbotapi.types.communities.Community] (`id`: [dev.inmo.tgbotapi.types.communities.CommunityId],
+ *   `name`) the chat was added to
+ * - [onCommunityChatRemoved] — trigger for the fieldless `community_chat_removed` service event
+ * - [waitCommunityChatAdded] — expectation returning a flow of [dev.inmo.tgbotapi.types.communities.CommunityChatAdded]
+ * - [dev.inmo.tgbotapi.types.chat.ExtendedChat.community] — the community a chat belongs to
+ *   (`ChatFullInfo.community`), available directly from [getChat] without any cast
+ */
+suspend fun main(vararg args: String) {
+    val botToken = args.first()
+    val isDebug = args.any { it == "debug" }
+    val isTestServer = args.any { it == "testServer" }
+
+    if (isDebug) {
+        setDefaultKSLog(
+            KSLog { level: LogLevel, tag: String?, message: Any, throwable: Throwable? ->
+                println(defaultMessageFormatter(level, tag, message, throwable))
+            }
+        )
+    }
+
+    telegramBotWithBehaviourAndLongPolling(
+        botToken,
+        CoroutineScope(Dispatchers.IO),
+        testServer = isTestServer,
+    ) {
+        val me = getMe()
+        println("Bot info: $me")
+
+        // community_chat_added: the chat was added to a community
+        onCommunityChatAdded { message ->
+            val community = message.chatEvent.community
+            println("Chat ${message.chat.id} was added to community '${community.name}' (id=${community.id.long})")
+            send(message.chat.id, "This chat has joined the community: ${community.name}")
+
+            // community is exposed on ExtendedChat itself (ChatFullInfo.community) — no cast needed
+            val extended = getChat(message.chat.id)
+            println("getChat().community = ${extended.community?.name} / ${extended.community?.id?.long}")
+        }
+
+        // community_chat_removed: a fieldless event — the chat left its community
+        onCommunityChatRemoved { message ->
+            println("Chat ${message.chat.id} was removed from its community")
+            send(message.chat.id, "This chat has left its community")
+        }
+
+        // Inspect the current chat's community on demand
+        onCommand("community") {
+            val community = getChat(it.chat.id).community
+            reply(
+                it,
+                if (community != null) {
+                    "Community: ${community.name} (id=${community.id.long})"
+                } else {
+                    "This chat is not part of any community"
+                }
+            )
+        }
+
+        // waitCommunityChatAdded expectation: suspend until this chat is added to a community
+        onCommand("wait_community") {
+            reply(it, "Waiting for this chat to be added to a community...")
+            val event = waitCommunityChatAdded().first()
+            reply(it, "Chat added to community: ${event.community.name} (id=${event.community.id.long})")
+        }
+
+        allUpdatesFlow.subscribeSafelyWithoutExceptions(this) {
+            println(it)
+        }
+    }.second.join()
+}

settings.gradle

@@ -83,3 +83,5 @@ include ":RichMessagesBot"
 include ":JoinRequestQueriesBot"
 
 include ":EphemeralMessagesBot"
+
+include ":CommunitiesBot"