I using React & Redux and I trying fetch data from JSON API. But I cant read my fetched data in components.

It returning a Uncaught TypeError: this.props.categories.map is not a function error.

I dont know why returning this. Sometimes fetch process goes into infinite loop Please help me!

My Action Codes :

export function getCategogiesSuccess(categories) {
    return { type: actionTypes.GET_CATEGORIES_SUCCESS, payload: categories };
}

export function getCategories() {
    return function (dispatch) {
        let url = "http://localhost:3000/categories";
        return fetch(url)
            .then(response => response.json())
            .then(result => {
                dispatch(getCategogiesSuccess(result));
            });
    };
}

My Reducer Codes :

export default function categoryListReducer(
    state = initialState.currentCategory,
    action,
) {
    switch (action.type) {
        case actionTypes.GET_CATEGORIES_SUCCESS:
            return action.payload;

        default:
            return state;
    }
}

Initial States :

export default {
    currentCategory: {},
    categories: [],
};

View Component Codes :

class CategoryList extends Component {
    componentDidMount() {
        this.props.actions.getCategories();
    }

    render() {
        return (
            <div>
                <h3>Categories</h3>
                <ListGroup>
                    {this.props.categories.map(category => (
                        <ListGroupItem
                            onClick={() => this.selectCategory(category)}
                            key={category.id}
                        >
                            {category.categoryName}
                        </ListGroupItem>
                    ))}
                </ListGroup>
            </div>
        );
    }
}

function mapStateToProps(state) {
    return {
        categories: state.categoryListReducer,
    };
}

function mapDispatchToProps(dispatch) {
    return {
        actions: {
            getCategories: bindActionCreators(
                categoryActions.getCategories,
                dispatch,
            ),
        },
    };
}

export default connect(mapStateToProps, mapDispatchToProps)(CategoryList);