Question

我有一个node.js服务器来获取我的帖子数据。基本上它使用过滤器和订单获取集合中的所有文档：

var ref = db.collection('posts');
var visible = request.query.visible;
var query = null;

if(visible === true) {
  query = ref.where('visible', '==', true)
    .orderBy('creation_date', 'desc');
}
else {
  query = ref.orderBy('creation_date', 'desc');
}

query.get()
  .then(res => {
    result.send(res);
  })
  .catch(err => {
    result.status(500).send(err);
  });

在客户端，我向服务器发出Ajax请求并循环收到的项目。

在firestore类中使用Ajax Request GetPosts（）函数

var firebaseApiRequest = AjaxRequest(`${this.apiUrl}/posts`, 'GET');
  firebaseApiRequest.send();

  firebaseApiRequest.onreadystatechange = function () {
    if(this.readyState === 4) {
      if(this.status === 200) resolve(JSON.parse(this.responseText));
      else {
        resolve([]);
      }
    }
  }

index.js函数显示我从服务器收到的帖子

let firestoreAPI = new firestore();
firestoreAPI.GetPosts().then(posts => {
  posts.forEach(post => {
    console.log(post);
    let json = post.data();
    json.id = post.id;
    postsList.push(json);
  });
  BuildPosts();
});

在node.js服务器上工作正常，我收到了json的帖子。当代码到达 posts.forEach 时，我收到此错误：

未捕获（承诺）TypeError：posts.forEach不是函数

这是我从服务器回来的Json（我删除了一些敏感数据）

{
"_query": {
    "_referencePath": {
        "segments": ["posts"]
    },
    "_fieldFilters": [],
    "_fieldOrders": [{
        "_field": {
            "segments": ["creation_date"],
            "_formattedName": "creation_date"
        },
        "_direction": "DESCENDING"
    }],
    "_queryOptions": {}
},
"_readTime": "2018-01-27T18:50:36.587401000Z",
"_materializedDocs": [{
    "_fieldsProto": {
        "clicks": {
            "integerValue": "6",
            "valueType": "integerValue"
        },
        "title": {
            "stringValue": "Corso gratuito sviluppo giochi con Unity 3D",
            "valueType": "stringValue"
        },
        "creation_date": {
            "integerValue": "1516813022363",
            "valueType": "integerValue"
        },
        "author": {
            "stringValue": "xcoding.it",
            "valueType": "stringValue"
        },
        "url": {
            "stringValue": "https://www.xcoding.it/corso/le-basi-di-unity-3d/",
            "valueType": "stringValue"
        },
        "creation_user": {
            "stringValue": "marcodz554@gmail.com",
            "valueType": "stringValue"
        },
        "edit_date": {
            "integerValue": "1516871809344",
            "valueType": "integerValue"
        },
        "edit_user": {
            "stringValue": "marcodz554@gmail.com",
            "valueType": "stringValue"
        },
        "visible": {
            "booleanValue": true,
            "valueType": "booleanValue"
        },
        "text": {
            "stringValue": "Corso base per i principianti con Unity3D che ricopre la maggior parte dei punti per scoprire questo engine. Completamente in lingua italiana e ben redatto, unica pecca la mancanza di video-guide annesse.",
            "valueType": "stringValue"
        },
        "type": {
            "stringValue": "corso",
            "valueType": "stringValue"
        }
    },
    "_readTime": "2018-01-27T18:50:36.587401000Z",
    "_createTime": "2018-01-24T09:01:41.929842000Z",
    "_updateTime": "2018-01-26T14:15:31.739188000Z"
}, {
    "_fieldsProto": {
        "creation_date": {
            "integerValue": "1516812951013",
            "valueType": "integerValue"
        },
        "author": {
            "stringValue": "brackeys.com",
            "valueType": "stringValue"
        },
        "url": {
            "stringValue": "https://www.youtube.com/user/Brackeys",
            "valueType": "stringValue"
        },
        "creation_user": {
            "stringValue": "marcodz554@gmail.com",
            "valueType": "stringValue"
        },
        "visible": {
            "booleanValue": true,
            "valueType": "booleanValue"
        },
        "text": {
            "stringValue": "Canale Youtube rifornito ogni due giorni circa con video inerenti a Unity3D. Ottime spiegazioni e facile da capire con una conoscenza base della lingua inglese.",
            "valueType": "stringValue"
        },
        "type": {
            "stringValue": "canale",
            "valueType": "stringValue"
        },
        "clicks": {
            "integerValue": "4",
            "valueType": "integerValue"
        },
        "title": {
            "stringValue": "Brackeys",
            "valueType": "stringValue"
        }
    },
    "_readTime": "2018-01-27T18:50:36.587401000Z",
    "_createTime": "2018-01-24T12:06:00.792552000Z",
    "_updateTime": "2018-01-25T11:04:57.606426000Z"
}]
}

Answer 1

鉴于您展示的JSON，它确实在您返回的对象上没有forEach。

我看到的唯一数组是_materializedDocs，您可以使用以下代码循环：

posts._materializedDocs.forEach(...)

Answer 2

我解决了在服务器端使用docs DATA和ID构建自定义Json。

从Node.js服务器检索数据并在Javascript客户端中循环时出错

2 个答案: