redux-shelf/src/entities.js

Helper reducers and actions to take away your boilerplate code from both Data and Communication state types

import { methods } from './constants';
import ids from './ids';
import content from './content';

function of(type, selector) {
  if (selector) {
    return this.contentOf(type, selector);
  }
  return this.idsOf(type);
}

function idsOf(type) {
  const entity = this[type];
  if (entity && entity.ids) {
    return entity.ids;
  }
  return [];
}

function contentOf(type, selector) {
  const entity = this[type];
  if (entity && entity.content) {
    return entity.content[selector];
  }
  return undefined;
}

function generateActionType(type, method) {
  return `entities/${type}/${method}`;
}

function generateActionByMethod(method) {
  return (type, payload) => ({
    type: generateActionType(type, method),
    meta: { method, type },
    payload,
  });
}

export function remove(type, selector) {
  return {
    type: generateActionType(type, methods.REMOVE),
    meta: {
      method: methods.REMOVE,
      selector,
      type,
    },
  };
}

export const set = generateActionByMethod(methods.SET);

export const update = generateActionByMethod(methods.UPDATE);

function reducer(state = {}, action) {
  if (
    !action.type.startsWith('entities') ||
    !(action.meta && action.meta.type)
  ) {
    return state;
  }

  const entity = state[action.meta.type] || {};
  const newIds = ids(entity.ids, action);
  const newContent = content(entity.content, action);

  if (entity.content === newContent) {
    return state;
  }

  return {
    ...state,
    [action.meta.type]: {
      ids: newIds,
      content: newContent,
    },
  };
}

export default function entities(state, action) {
  const newState = reducer(state, action);
  newState.of = of;
  newState.idsOf = idsOf;
  newState.contentOf = contentOf;

  return newState;
}

entities.set = set;
entities.update = update;
entities.remove = remove;