javascript 猫鼬中的继承
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Inheritance in mongoose
提问by Erik
Hello I need to inherit my schemas in mongoose library. Are there complete plugins for that? Or how should I do that myself?
您好，我需要在 mongoose 库中继承我的模式。有没有完整的插件？或者我自己应该怎么做？
I need to inherit all pre, post, init middleware from a Base schema also.
我还需要从 Base 模式继承所有 pre、post、init 中间件。
采纳答案by hunterloftis
You may want to look at using a Mongoose Plugin:
你可能想看看使用猫鼬插件：
A plugin that does what you want 'out of the box' is here:
一个可以“开箱即用”的插件在这里：
回答by regretoverflow
For others looking for this functionality, Mongoose 3.8 now has Schema Inheritance via Discriminator functionality:
对于寻求此功能的其他人，Mongoose 3.8 现在具有通过鉴别器功能的模式继承：
回答by Michael A. Vickers
I know this is an oldie, but I arrived here looking for the answer to the same question and ended up doing something a little different. I don't want to use discriminators because all the documents are stored in the same collection.
我知道这是一个老生常谈，但我来到这里寻找同一问题的答案，最终做了一些不同的事情。我不想使用鉴别器，因为所有文档都存储在同一个集合中。
ModelBase.js
模型库
var db = require('mongoose');
module.exports = function(paths) {
var schema = new db.Schema({
field1: { type: String, required: false, index: false },
field2: { type: String, required: false, index: false }
}, {
timestamps: {
createdAt: 'CreatedOn',
updatedAt: 'ModifiedOn'
}
});
schema.add(paths);
return schema;
};
NewModel.js
新模型.js
var db = require('mongoose');
var base = require('./ModelBase');
var schema = new base({
field3: { type: String, required: false, index: false },
field4: { type: String, required: false, index: false }
});
db.model('NewModelItem', schema, 'NewModelItems');
All 4 fields will be in NewModelItem. Use ModelBase for other models where you want to use the same fields/options/etc. In my project I put the timestamps in there.
所有 4 个字段都将在 NewModelItem 中。将 ModelBase 用于要使用相同字段/选项/等的其他模型。在我的项目中，我把时间戳放在那里。
Schema.add is called in the Schema constructor so the model should be assembled as if all the fields were sent in the original constructor call.
Schema.add 在 Schema 构造函数中被调用，因此模型应该被组装，就好像所有字段都是在原始构造函数调用中发送的一样。
回答by Do Async
If you want to use different collections:
如果要使用不同的集合：
function extendSchema (Schema, definition, options) {
return new mongoose.Schema(
Object.assign({}, Schema.obj, definition),
options
);
}
Usage:
用法：
const UserSchema = new mongoose.Schema({
firstname: {type: String},
lastname: {type: String}
});
const ClientSchema = extendSchema(UserSchema, {
phone: {type: String, required: true}
});
回答by marian2js
Check the models of this framework for Mongoose:
检查 Mongoose 的这个框架的模型：
https://github.com/marian2js/rode#models-with-mongoose
https://github.com/marian2js/rode#models-with-mongoose
This is an example of who to extend shemas with this framework:
这是谁使用此框架扩展 shemas 的示例：
First of all define your schema inside a new "rode model":
首先在一个新的“罗德模型”中定义你的模式：
var rode = require('rode');
var User = rode.Model.extend({
name: 'User',
schema: {
name: {
type: 'String',
unique: true
},
email: String,
password: String
}
});
Now you should call extend method:
现在你应该调用扩展方法：
var Admin = User.extend({
name: 'Admin',
// The schema for admins is the schema for users + their own schema
schema: {
lastAccess: Date
}
});
But have in mint this note extracted from the framework github: "Both models will share the same collection on MongoDB. Documents of the extended models will have an attribute _type to differentiate."
但是，请记住从框架 github 中提取的此注释：“两个模型将在 MongoDB 上共享相同的集合。扩展模型的文档将具有属性 _type 以进行区分。”
