Fix #793 by adding pyramid_request property to Bolt context (#794)

Author: seratch

slack_bolt/adapter/pyramid/handler.py

@@ -45,14 +45,34 @@ def handle(self, request: Request) -> Response:
             if self.app.oauth_flow is not None:
                 oauth_flow: OAuthFlow = self.app.oauth_flow
                 if request.path == oauth_flow.install_path:
-                    bolt_resp = oauth_flow.handle_installation(to_bolt_request(request))
+                    bolt_req = _attach_pyramid_request_to_context(to_bolt_request(request), request)
+                    bolt_resp = oauth_flow.handle_installation(bolt_req)
                     return to_pyramid_response(bolt_resp)
                 elif request.path == oauth_flow.redirect_uri_path:
-                    bolt_resp = oauth_flow.handle_callback(to_bolt_request(request))
+                    bolt_req = _attach_pyramid_request_to_context(to_bolt_request(request), request)
+                    bolt_resp = oauth_flow.handle_callback(bolt_req)
                     return to_pyramid_response(bolt_resp)
         elif request.method == "POST":
-            bolt_req = to_bolt_request(request)
+            bolt_req = _attach_pyramid_request_to_context(to_bolt_request(request), request)
             bolt_resp = self.app.dispatch(bolt_req)
             return to_pyramid_response(bolt_resp)
 
         return Response(status=404, body="Not found")
+
+
+def _attach_pyramid_request_to_context(
+    bolt_req: BoltRequest,
+    request: Request,
+) -> BoltRequest:
+    # To enable developers to access request-scope attributes such as dbsession,
+    # this adapter exposes the underlying pyramid_request object to Bolt listeners
+    #
+    # Developers can access request props this way:
+    # @app.event("app_mention")
+    # def handle_app_mention_events(context, logger):
+    #     req = context["pyramid_request"]
+    #     all = req.dbsession.query(MyModel).all()
+    #     logger.info(all)
+    #
+    bolt_req.context["pyramid_request"] = request
+    return bolt_req