text: import React, { Component } from 'react';
  import { connect } from 'react-redux';
  import { fetchPost } from '../actions';
  import { Link } from 'react-router-dom';
  import { deletePost } from '../actions';
  import CommentsList from './comments_list';
  
  class PostsShow extends Component {
    componentDidMount(){
      if (!this.props.post){ //cache records. don't update if there is a post
        const { id } = this.props.match.params;
        this.props.fetchPost(id);
      }
    }
  
    onDeleteClick(){
      const { id } = this.props.match.params;
      this.props.deletePost(id, () => {
        this.props.history.push('/');
      });
    }
  
    render(){
      const { post } = this.props;
  
      if (!post){
        return <div>Loading...</div>;
      }
  
      return (
        <div>
          <Link to="/">Back to Index</Link>
          <button
            className="btn btn-danger pull-xs-right"
            onClick={this.onDeleteClick.bind(this)}
          >
            Delete Post
          </button>
          <h3>{post.title}</h3>
          <h6>Categories: {post.categories}</h6>
          <p>{post.content}</p>
          <CommentsList />
        </div>
      );
    }
  }
  
  function mapStateToProps({ posts }, ownProps){
    return { post: posts[ownProps.match.params.id] };
  }
  
  export default connect(mapStateToProps, { fetchPost, deletePost })(PostsShow);