README.md

Redux action creators - /src/actions/

This folder contains all of the Redux actions for the project. If this is your first time working with Redux, then taking a read through the Redux docs would probably be a good idea.

Action type definitions

All actions in perf.html are fully typed using Flow. These types are located in /src/types/actions.js and are built using a union of the action objects.

Preferred practices for actions

Actions in perf.html are kept relatively simple. There are two types of action creators in this project–action creators that return an Action or an action creator that returns a ThunkAction (see Redux Thunk for additional reading.) If an action creator needs access to different parts of the state, then it may be tempting to use the getState parameter from a ThunkAction. However, at this time we prefer not to directly access the state in a ThunkAction. Instead, the connected component should look up the value using a selector, then pass it into the action creator as a parameter.

Don't access getState in ThunkAction creators

export function doThunkAction() {
  return (dispatch, getState) => {
    // Don't do this!
    const requiredData = getState().requiredData;

    myAction(requiredData).then(() => {
      dispatch({ type: "ACTION_PERFORMED" })
    });
  };
}

Instead pass in required data as an argument for ThunkAction creators

export function doThunkAction(requiredData) {
  return dispatch => {
    myAction(requiredData).then(() => {
      dispatch({ type: "ACTION_PERFORMED" });
    });
  };
}

Testing actions

For our approach for testing actions, please read the store tests documentation.