Я пытаюсь заполнить MongoDB данные для выбора HTML.
Это то, что я сделал до сих пор
Я создал базу данных books и создал коллекцию AuthorDB
Я вручную вставил данные (чтобы проверить, действительно ли они работают)
Но когда я использовал postman для получения данных, я получаю пустой массив , что означает отсутствие данных. (Но я вставил данные в AuthorDB коллекцию)
Вот мой server.js
const express = require('express');
const bodyParser = require('body-parser');
const cors = require('cors');
const mongoose = require('mongoose');
const BookDB = require('./book-dbmodel');
const AuthorDB = require('./author-dbmodel');
const app = express();
const router = express.Router();
app.use(bodyParser.json());
app.use(cors());
app.use('/books', router);
//connect to books database
mongoose.connect('mongodb://127.0.0.1:27017/books', {useNewUrlParser: true});
const connection = mongoose.connection;
connection.once('open', () => {
console.log("Connected to MongoDB via port 27017");
});
app.listen(4000, () => {
console.log('Listening to port 4000');
});
// add book http://localhost:4000/books/add
router.route('/add').post((req, res) => {
let bookDB = new BookDB(req.body);
bookDB.save().then((bookDB) => {
res.status(200).send(`${bookDB} Added!`);
}).catch((err) => {
res.status(400).send({message: err});
});
});
//get all authors http://localhost:4000/books/authors
router.route('/authors').get((req, res) => {
AuthorDB.find((err, authors) => {
if(err) throw err;
res.status(200).send(authors);
});
});
//get books by author name http://localhost:4000/books/authors/authorName
router.route('/authors/authorName').get((req, res) => {
let authorName = req.params.authorName;
BookDB.find({firstName: {$regex: `${authorName}`, $options: "i"}}, (err, books) => {
if(err) throw err;
res.status(200).send(books);
});
});
А это мой App.js во фронтэнде:
import React, {Component} from 'react';
import axios from 'axios';
const ShowAuthors = (props) => (
<option value={props.author.firstName}>{props.author.firstName}</option>
);
export default class AddBooks extends Component{
constructor(props){
super(props);
this.state = {
authorArray: [],
name: '',
isbn: 0,
author: '',
price: 0,
yearOfPublication: 0,
publisher: ''
}
}
//to get author list on dropdown select
componentDidMount(){
axios.get('http://localhost:4000/books/authors/')
.then(authors => {
console.log(authors.data);
this.setState({
authorArray: authors.data
});
}).catch(err => {
console.log(err);
});
}
getAuthors(){
return this.state.authorArray.map((currentAuthor, id) => {
return <ShowAuthors author={currentAuthor} key={id} />
});
}
onSubmit(){
}
onChangeName(){
}
onChangeISBN(){
}
render(){
return(
<div className="container">
<h1>Add Books</h1>
<form onSubmit={this.onSubmit}>
<div className="form-group">
<label htmlFor="book-name">Book Name</label>
<input
value={this.state.name}
onChange={this.onChangeName}
type="text" className="form-control" id="book-name" aria-describedby="emailHelp" placeholder="Book Name"/>
</div>
<div className="form-group">
<label htmlFor="book-isbn">ISBN</label>
<input
value={this.state.isbn}
onChange={this.onChangeISBN}
type="number" className="form-control" id="book-isbn" aria-describedby="emailHelp" placeholder="ISBN"/>
</div>
<div className="form-group">
<label htmlFor="author-name">Authors</label>
<select
className="form-control" name="authors" id="authors">
{this.getAuthors()} {/* this doesn't return anything but an empty array */}
</select>
</div>
<div className="form-group">
<label htmlFor="book-price">Book Price</label>
<input type="number" className="form-control" id="book-price" name="book-price" aria-describedby="emailHelp" placeholder="Book Price"/>
</div>
<div className="form-group">
<label htmlFor="book-year">Published Year</label>
<input type="number" className="form-control" id="book-year" name="book-year" aria-describedby="emailHelp" placeholder="Year"/>
</div>
<div className="form-group">
<label htmlFor="book-publisher">Book Publisher</label>
<input type="number" className="form-control" id="book-publisher" name="book-publisher" aria-describedby="emailHelp" placeholder="Publisher"/>
</div>
</form>
</div>
);
}
}
А это моя визуализация mongodb:
А это моя AuthorDB модель схемы:
const mongoose = require('mongoose');
const Schema = mongoose.Schema;
let AuthorDB = new Schema({
firstName: {type: String},
lastName: {type: String},
nationality: {type: String}
});
module.exports = mongoose.model('AuthorDB', AuthorDB);