Error: TypeError: path must be a string
浏览器控制台指向ItemCtrl.js：35
console.log('Error: ' + data);
错误的堆栈跟踪如下所示：
TypeError：path必须是字符串 在Query.where（/Users/Name/Downloads/dev/v16/node_modules/mongoose/lib/query.js:593:11） 在Function.where（/Users/Name/Downloads/dev/v16/node_modules/mongoose/lib/model.js:1040:18） 在模特。 （/Users/Name/Downloads/dev/v16/app/models/item.js:44:35）...
似乎错误来自 /app/models/item.js 中的一行
特别是在else if声明中..
因为else if已注释掉，if作品和else都有效。
// load mongoose since we need it to define a schema and model
var mongoose = require('mongoose');
var ItemSchema = mongoose.Schema({
title : String,
position: Number
});
// before validation starts, the number of Items is counted..afterwards, the position is set
ItemSchema.pre("validate", function(next) {
var doc = this;
// if 'position' is not filled in, fill it in
// not using !position because 0 might be a valid value
if(typeof doc.position !== "number") {
// count the number of Items *
// use mongoose.model to fetch the model because it is not compiled yet
mongoose.model("Item").count(function(err, num) {
// if there was an error, pass it to next()
if(err)
return next(err);
// set the position, then call next();
doc.position = num;
return next();
});
} else if(typeof doc.position == "number") {
console.log('yes, a number');
// check if there is an existing document with the same position
// use mongoose.model to fetch the model because the model is not compiled yet
mongoose.model("Item").where({_id: {$ne: doc._id}, position: doc.position}).count( function (err, count) {
// if there was an error, pass it to next()
if(err)
return next(err);
// if there is a doc with the SAME position, execute an update to MOVE DOWN all the $gte docs
if(count > 0) {
// use mongoose.model to fetch the model because the model is not compiled yet
mongoose.model("Item").update({position: {$gte: doc.position}}, {position: {$inc: 1}}, {multi: 1}, function(err, numAffected) {
console.log(numAffected);
// Call next() (with or without an error)
next(err);
});
} else {
// there are no docs that need to move down, so call next()
next();
}
});
} else {
// there is no need to count or update positions, so call next()
next();
}
});
module.exports = mongoose.model('Item', ItemSchema);
- 数据的路径是：
- /public/views/CreateItem.html
中的表单字段- 到/public/js/controllers/ItemCtrl.js
- 到/public/js/services/ItemService.js
- 到/app/routes.js
- 到/app/models/item.js
- 并且可以在json的localhost：8080 / api / items
中查看数据
/public/views/CreateItem.html
<form>
<div class="form-group">
<!-- BIND THESE VALUES TO formData.value IN ANGULAR -->
<input type="text" class="form-control input-lg text-center" placeholder="Item" ng-model="formData.title">
<input type="number" class="form-control input-lg text-center" placeholder="0" ng-model="formData.position">
</div>
<!-- createItem() WILL CREATE THE NEW ITEM VIA ANGULAR THROUGH NODE API TO MONGOOSE -->
<button type="submit" class="btn btn-primary btn-lg" ng-click="createItem()">Add Item</button>
</form>
/public/js/controllers/ItemCtrl.js
angular.module('ItemCtrl', [])
// inject the Item service.factory into our controller
.controller('ItemController', function($scope, $http, Items, isEmptyObjectFilter) {
$scope.formData = {};
// CREATE ==================================================================
// when submitting the add form, send the text to the node API
$scope.createItem = function() {
// validate the formData (using our exentions.js .filter) to make sure that something is there..if form is empty, nothing will happen
if (!isEmptyObjectFilter($scope.formData)) {
// call the create function from our service (returns a promise object)
Items.create($scope.formData)
// if successful creation, call our get function to get all the new items
.success(function(data) {
$scope.formData = {}; // clear the form so our user is ready to enter another
$scope.items = data; // assign our new list of items
})
.error(function(data) {
console.log('Error: ' + data);
});
}
};
});
/public/js/services/ItemService.js
angular.module('ItemService', [])
// super simple service
// each function returns a promise object
.factory('Items', function($http) {
return {
get : function() {
return $http.get('/api/items');
},
create : function(itemData) {
return $http.post('/api/items', itemData);
}
}
});
/app/routes.js
// load the item model
var Item = require('./models/item');
// expose the routes to our app with module.exports
module.exports = function(app) {
// create item and send back all items after creation
app.post('/api/items', function(req, res) {
console.log(req.body.position);
// create an item, information comes from AJAX request from Angular
Item.create({
title : req.body.title,
position : req.body.position
}, function(err, item) {
if (err)
res.send(err);
// get and return all the items after you create another
Item.find(function(err, items) {
if (err)
res.send(err)
res.json(items);
});
});
});
};
答案 0 :(得分：2)
这里的问题是，mongoose API实际上并没有像您尝试的那样使用where。
用于Model.where的mongoose v3.8.8的文档显示您可以以ActiveRecord样式方式使用它，使用条件方法（如'age'链接属性名称（如gte） ）形成一个查询：
User.find({age: {$gte: 21}, callback)
相当于
User.where('age').gte(21).exec(callback)
您的代码使用Model#find的哈希条件样式，而不是where的链式方法样式。
这是应该重写的行：
mongoose.model("Item").where({_id: {$ne: doc._id}, position: doc.position}).count( function (err, count) {
最简单的方法是删除最后的.count，然后将.where更改为.count，因为mongoose的Model#count需要条件的哈希值就像你在这里一样。代码应该像这样工作：
mongoose.model("Item").count({_id: {$ne: doc._id}, position: doc.position}, function (err, count) {
如果您想使用.where语法，您需要这样做：
mongoose.model("Item").where('_id').ne(doc._id).where('position').equals(doc.position).count( function(err, count)