Can I use condition in my action reducer?

Basically, in our case, we need to either get an alerts list that shows the first few items (mounting it first time in the DOM) or show the initial list + the next list (clicking a load more button).

Hence we needed to do this condition in our GET_ALERTS action:

case "GET_ALERTS":
    if (action.initialList) {
        newState.list = [...newState.list, action.res.data.list];
    } else {
        newState.list = newState.list.concat(
            action.res.data.list
        );
    }

And when we call the action reducer in our Alerts component, we need to indicate whether initialList is true or false.

E.g.

componentDidMount() {
    this.props.getAlerts(pageNum, true);
}

markAllAsRead() {
   // other code calling api to mark all as read
   this.props.getAlerts(pageNum, false);
}

readMore() {
  // other code that increases pageNum state counter
  this.props.getAlerts(pageNum, true);
}

Anyway in such a case, is it fine to use conditional statement in the reducer?

from Can I use condition in my action reducer?