TypeError：无法在字符串上创建属性“_id”

Question

我正在创建简单的 REST API 我有一个用于发布/数据的端点，用于将数据从外部 API 保存到 MongoDB，

这是我目前所拥有的：

app.post('/data', (req, res) => {
    let url = 'https://api.themoviedb.org/3/movie/401478/reviews?api_key=4d9c9de3bdf0d3b6837c49c086e3b190';
    request(url, function (error, response, body) {
        db.collection('data').insert(body, (err, result) => {
            if (err) {
                res.send({
                    'error': 'An error has occured'
                });
            } else {
                    res.send(result.ops[0]);
            }
        });
    });
});

当我在控制台中的邮递员localhost:8000/data 中测试 api 时出现错误：

TypeError：无法在字符串上创建属性“_id”

我在这里做错了什么？

Answer 1

body 是 JSON 字符串，要将其转换为 JSON 对象，请使用 JSON.parse(body)

app.post('/data', (req, res) => {
    let url = 'https://api.themoviedb.org/3/movie/401478/reviews?api_key=4d9c9de3bdf0d3b6837c49c086e3b190';
    request(url, function (error, response, body) {

        // convert to JSON
        var bodyJson = JSON.parse(body)

        db.collection('data').insert(bodyJson, (err, result) => {
            if (err) {
                res.send({
                    'error': 'An error has occured'
                });
            } else {
                    res.send(result.ops[0]);
            }
        });
    });
});

Answer 2

根据您之前的问题，我看到您的 body var 当前是一个字符串，因此您需要更改它。

app.post('/data', (req, res) => {
let url = 'https://api.themoviedb.org/3/movie/401478/reviews?api_key=4d9c9de3bdf0d3b6837c49c086e3b190';
request(url, function (error, response, body) {
    var insertObj = JSON.parse(body)
    db.collection('data').insert(insertObj, (err, result) => {
        if (err) {
            res.send({
                'error': 'An error has occured'
            });
        } else {
                res.send(result.ops[0]);
        }
    });
});
});

Answer 3

如你所见，“_id 不能是字符串”

当您请求网址“https://api.themoviedb.org/3/movie/401478/reviews?api_key=4d9c9de3bdf0d3b6837c49c086e3b190”时

它将返回类似于 JSON 的字符串

'{"id":401478,"page":1,"results":[{"author":"Gimly","content":"There is some decent fun to be found in _Beyond Anarchy_. It's more _Escape from LA_ than it is _Death Race 2000_, but still an entry in the franchise, which brings me to the core problem of Beyond Anarchy: Is it even really a _Death Race_ movie? The answer is yes, but to go beyond that an ask: Should it have been a _Death Race_ movie? The answer's probably no.\r\n\r\nAs I said to begin with, I had some fun with the movie, but the things that kept bringing it down were its awkward, half-hearted attatchments to the movies in the series that had gone before it. If they had have abandoned those sentiments completely, it probably would have made a better viewing experience, but then, if that had been the case, how could you call it _Death Race 4_? The opposite approach probably would have worked too, having Beyond Anarchy be an actual sequel that follows _Death Race 3_ and what came before in a way that makes sense, but then, it couldn't have been even close to the movie that we got.\r\n\r\nInstead we have _Beyond Anarchy's_ sequel-limbo status, a movie that I don't regret watching, but that also can't really work for people who are fans of the _Death Race_ franchise, or for people who have never even seen a Death Race movie.\r\n\r\n_Final rating:★★½ - Had a lot that appealed to me, didn’t quite work as a whole._","id":"5af426b50e0a2639430091df","url":"https://www.themoviedb.org/review/5af426b50e0a2639430091df"}],"total_pages":1,"total_results":1}'

所以你必须做 JSON.parse 以使 body 从字符串更改为对象（插入数据到 mongo 必须是对象）

let url = 'https://api.themoviedb.org/3/movie/401478/reviews?api_key=4d9c9de3bdf0d3b6837c49c086e3b190';
request(url, function (error, response, body) {
    body = JSON.parse(body);
    db.collection('data').insert(body, (err, result) => {
        //
    });
});