trends.js

const initialState = {
    result: [
        []
    ],
    sending: false,
    keyArr: [],
    dailyTrending: false
};

export default function(state = initialState, action) {
    const {
        type,
        payload
    } = action;
    switch (type) {

        case 'SENDING':
            return {
                ...state,
                sending: true
            }
            case 'TREND_RECEIVED':
                return {
                    ...state,
                    sending: false,
                        result: payload
                }

                case 'TREND_ERROR':
                    return {
                        ...state,
                        sending: false
                    }

                    case 'TRENDING':
                        return {
                            ...state,
                            dailyTrending: true
                        }
                        case 'TRENDING_RECEIVED':
                            return {
                                ...state,
                                dailyTrending: false,
                                    keyArr: payload
                            }

                            case 'TRENDING_ERROR':
                                return {
                                    ...state,
                                    dailyTrending: false
                                }
                                default:
                                    return state
    }
}