feat: support slack block kits and view events

packages/bottender/src/context/SlackContext.ts

@@ -0,0 +1,136 @@
+import sleep from 'delay';
+import warning from 'warning';
+import { SlackOAuthClient, SlackTypes } from 'messaging-api-slack';
+
+import Context from './Context';
+import SlackEvent from './SlackEvent';
+import { PlatformContext } from './PlatformContext';
+
+export default class SlackContext extends Context<SlackOAuthClient, SlackEvent>
+  implements PlatformContext {
+  /**
+   * The name of the platform.
+   *
+   */
+  get platform(): string {
+    return 'slack';
+  }
+
+  /**
+   * Delay and show indicators for milliseconds.
+   *
+   */
+  async typing(milliseconds: number): Promise<void> {
+    if (milliseconds > 0) {
+      await sleep(milliseconds);
+    }
+  }
+
+  /**
+   * Sends a message to the channel of the session.
+   *
+   * https://api.slack.com/methods/chat.postMessage
+   */
+  postMessage(
+    message:
+      | {
+          text?: string;
+          attachments?: SlackTypes.Attachment[] | string;
+          blocks?: SlackTypes.Block[] | string;
+        }
+      | string,
+    options?: {}
+  ): Promise<any> {
+    const channelId = this._getChannelIdFromSession();
+
+    if (!channelId) {
+      warning(
+        false,
+        'postMessage: should not be called in context without session'
+      );
+      return Promise.resolve();
+    }
+
+    this._isHandled = true;
+
+    return this._client.postMessage(channelId, message, {
+      threadTs: this._event.rawEvent.thread_ts,
+      ...options,
+    });
+  }
+
+  /**
+   * Sends an ephemeral message to the session owner.
+   *
+   * https://api.slack.com/methods/chat.postMessage
+   */
+  postEphemeral(
+    message:
+      | {
+          text?: string;
+          attachments?: SlackTypes.Attachment[] | string;
+          blocks?: SlackTypes.Block[] | string;
+        }
+      | string,
+    options?: {}
+  ): Promise<any> {
+    const channelId = this._getChannelIdFromSession();
+
+    if (!channelId) {
+      warning(
+        false,
+        'postMessage: should not be called in context without session'
+      );
+      return Promise.resolve();
+    }
+
+    this._isHandled = true;
+
+    return this._client.postEphemeral(
+      channelId,
+      (this._session as any).user.id,
+      message,
+      options
+    );
+  }
+
+  /**
+   * Open a view (modal) and use private_metadata to keep channelId for session key
+   *
+   * https://api.slack.com/methods/view.open
+   */
+  openView(view: {}, triggerId: string): Promise<any> {
+    return this._client.callMethod('views.open', {
+      view: JSON.stringify({
+        ...view,
+        private_metadata: JSON.stringify({
+          ...(view.private_metadata || {}),
+          channelId: this.event.rawEvent.channel.id,
+        }),
+      }),
+      trigger_id: triggerId,
+    });
+  }
+
+  /**
+   * Send text to the owner of the session.
+   *
+   */
+  sendText(text: string, options?: {}): Promise<any> {
+    return this.postMessage(text, options);
+  }
+
+  // FIXME: this is to fix type checking
+  _getChannelIdFromSession(): string | null {
+    if (!this._session) return null;
+    if (
+      typeof this._session.channel === 'object' &&
+      this._session.channel &&
+      this._session.channel.id &&
+      typeof this._session.channel.id === 'string'
+    ) {
+      return this._session.channel.id;
+    }
+    return null;
+  }
+}

packages/bottender/src/slack/SlackConnector.ts

@@ -138,6 +138,11 @@ export default class SlackConnector
       return rawEvent.channelId;
     }
 
+    // For slack modal
+    if (rawEvent.view && rawEvent.view.private_metadata) {
+      return JSON.parse(rawEvent.view.private_metadata).channelId;
+    }
+
     // For reaction_added format
     if (
       rawEvent.item &&
@@ -159,7 +164,9 @@ export default class SlackConnector
     let userFromBody;
     if (
       rawEvent.type === 'interactive_message' ||
-      rawEvent.type === 'block_actions'
+      rawEvent.type === 'block_actions' ||
+      rawEvent.type === 'view_submission' ||
+      rawEvent.type === 'view_closed')
     ) {
       userFromBody = rawEvent.user.id;
     } else {

packages/bottender/src/slack/SlackEvent.ts

@@ -102,10 +102,15 @@ export type BlockActionEvent = UIEvent & {
   type: 'block_actions';
 };
 
+export type ViewEvent = UIEvent & {
+  type: 'view_submission' | 'view_closed';
+};
+
 export type SlackRawEvent =
   | Message
   | InteractiveMessageEvent
-  | BlockActionEvent;
+  | BlockActionEvent
+  | ViewEvent;
 
 export default class SlackEvent implements Event<SlackRawEvent> {
   _rawEvent: SlackRawEvent;
@@ -225,6 +230,22 @@ export default class SlackEvent implements Event<SlackRawEvent> {
     return this._rawEvent.type === 'block_actions';
   }
 
+  /**
+   * Determine if the event is a view submission event.
+   *
+   */
+  get isViewSubmission(): boolean {
+    return this._rawEvent.type === 'view_submission';
+  }
+
+  /**
+   * Determine if the event is a view closed event.
+   *
+   */
+  get isViewClosed(): boolean {
+    return this._rawEvent.type === 'view_closed';
+  }
+
   /**
    * Determine if the event is an UI Event (block actions or interactive message)
    *