#6 added joiin-leave handler

src/service/vk/handlers/JoinLeaveHandler.ts

@@ -0,0 +1,61 @@
+import { VkEventHandler } from "./VkEventHandler";
+import { GroupMemberContext } from "vk-io";
+import { NextMiddleware } from "middleware-io";
+import logger from "../../logger";
+import { UsersUserFull } from "vk-io/lib/api/schemas/objects";
+import { ConfigGroup } from "../types";
+import { ExtraReplyMessage } from "telegraf/typings/telegram-types";
+
+interface Fields {}
+
+interface Values {
+  user: UsersUserFull;
+  group: ConfigGroup;
+  isJoined: boolean;
+  isLeave: boolean;
+  count: number;
+}
+
+export class JoinLeaveHandler extends VkEventHandler<Fields, Values> {
+  public execute = async (
+    context: GroupMemberContext,
+    next: NextMiddleware
+  ) => {
+    const user = await this.getUserByID(String(context.userId));
+    const dir = context.isJoin ? "joined" : "left";
+    const count = await this.getMembersCount();
+
+    logger.debug(
+      `vk, group ${this.group.name}: ${user.first_name} ${user.last_name} ${dir} the group`
+    );
+
+    const parsed = this.template.theme({
+      user,
+      group: this.group,
+      isJoined: context.isJoin,
+      isLeave: context.isLeave,
+      count,
+    });
+
+    const extras: ExtraReplyMessage = {
+      parse_mode: "Markdown",
+      disable_web_page_preview: true,
+    };
+
+    await this.telegram.sendMessageToChan(this.channel.id, parsed, extras);
+
+    await next();
+  };
+
+  /**
+   * Returns current members count
+   * @private
+   */
+  private getMembersCount = async () => {
+    const resp = await this.instance.api.groups.getMembers({
+      group_id: this.group.id.toString(),
+    });
+
+    return resp.count;
+  };
+}