fix: unmarshall payload to avoid panic

go/pkg/bertybot/handlers.go

@@ -106,13 +106,7 @@ func (b *Bot) handleEvent(ctx context.Context, event *messengertypes.StreamEvent
 			}
 			b.callHandlers(context, UserMessageHandler)
 		case messengertypes.AppMessage_TypeGroupInvitation:
-			context.ReplyString("I'll join asasp !")
-
-			invLink := context.EventPayload.(*messengertypes.AppMessage_GroupInvitation).Link
-
-			req := messengertypes.ConversationJoin_Request{Link: invLink}
-			ctx.Client.ConversationJoin(ctx.Context, &req)
-
+			b.callHandlers(context, IncomingGroupInvitationHandler)
 		default:
 			return fmt.Errorf("unsupported interaction type: %q", context.Interaction.Type)
 		}

go/pkg/bertybot/recipes.go

@@ -131,17 +131,21 @@ func DelayResponseRecipe(duration time.Duration) Recipe {
 	return recipe
 }
 
-// AutoAcceptIncomingContactRequestRecipe makes the bot "click" on the "accept" button automatically.
+// AutoAcceptIncomingGroupInviteRecipe makes the bot "click" on the "join" button automatically.
 func AutoAcceptIncomingGroupInviteRecipe() Recipe {
 	recipe := map[HandlerType][]Handler{}
 	recipe[IncomingGroupInvitationHandler] = []Handler{
-		func(ctx Context) {
-			ctx.ReplyString("I'll join asasp !")
+		func(context Context) {
+			context.ReplyString("I'll join asasp !")
 
-			invLink := ctx.EventPayload.(*messengertypes.AppMessage_GroupInvitation).Link
+			payload, err := context.Interaction.UnmarshalPayload()
+			if err != nil {
+				return
+			}
+			invLink := payload.(*messengertypes.AppMessage_GroupInvitation).Link
 
 			req := messengertypes.ConversationJoin_Request{Link: invLink}
-			ctx.Client.ConversationJoin(ctx.Context, &req)
+			context.Client.ConversationJoin(context.Context, &req)
 		},
 	}
 	return recipe