[英]Generate auto increment field using Mongoose?
我有一個數據庫,包括四個字段id,text,key,status。 我想添加另一個名為order的字段,該字段由一個數字組成,這是一個代表的表示。 我也有刪除文件的功能,所以刪除順序不連續后,我也希望訂單連續不重復。 如果從數據庫中刪除某些文檔,則會根據數據庫中的文檔數自動調整。我有兩個文件index.js和items.js。 我使用過mongoose,body-parser和expressjs。
我的訂單字段不重復且連續。
index.js
var express = require('express');
var app = express();
var bodyParser = require('body-parser');
var mongoose = require('mongoose');
var cors = require('cors');
app.use(bodyParser.json());
app.use(cors());
Items = require('./items.js');
mongoose.connect('mongodb://localhost/taskDb');
var db = mongoose.connection;
app.get("/", (req, res) => {
res.send('Visit /api/*****');
});
app.get("/api/items", (req, res) => {
Items.getItems(function (err, items) {
if (err) {
throw err;
}
res.json(items);
});
});
app.post("/api/items", (req, res) => {
var item = req.body;
console.log(item + "item post");
Items.addItem(item, function (err, items) {
if (err) {
throw err;
}
res.json(items);
});
});
app.delete("/api/items/:_key", (req, res) => {
var key = req.params._key;
Items.deleteItem(key, function (err, items) {
if (err) {
throw err;
}
res.json(items);
});
});
app.delete("/api/items/", (req, res) => {
var status = "completed";
Items.deleteItems(status, function (err, items) {
if (err) {
throw err;
}
res.json(items);
});
});
app.put("/api/items/:_key", (req, res) => {
var key = req.params._key;
var item = req.body;
Items.updateItem(key, item, {}, function (err, items) {
if (err) {
throw err;
}
res.json(items);
});
});
app.put("/api", (req, res) => {
Items.updateAllItem(function (err, items) {
if (err) {
throw err;
}
res.json(items);
});
});
app.listen(3005, () => {
console.log('Listening on port 3005...');
});
items.js
var mongoose = require('mongoose');
var itemSchema = mongoose.Schema({
text: {
type: String,
required: true
},
key: {
type: String,
required: true
},
status: {
type: String,
required: true
},
order: {
type: Number,
required: true
}
});
var Item = module.exports = mongoose.model('item', itemSchema);
module.exports.getItems = function (callback, limit) {
Item.find(callback).limit(limit);
}
module.exports.addItem = function (item, callback) {
Item.create(item, callback);
}
module.exports.deleteItem = function (key, callback) {
var query = { key: key };
Item.remove(query, callback);
}
module.exports.deleteItems = function (status, callback) {
var query = { status: status };
Item.remove(query, callback);
}
module.exports.updateItem = function (key, item, options, callback) {
var query = { key: key };
var update = {
text: item.text,
key: item.key,
status: item.status
}
Item.updateOne(query, update, {}, callback);
}
module.exports.updateItem = function (key, item, options, callback) {
var query = { key: key };
var update = {
text: item.text,
key: item.key,
status: item.status
}
Item.updateOne(query, update, {}, callback);
}
module.exports.updateAllItem = function (callback) {
console.log("Update All");
Item.update({}, { $set: { "status": "completed" } }, { "multi": true }, callback);
}
module.exports.changeItemsOrder = function (items, callback) {
var query = Item.remove({}, callback);
assert.ok(!(query instanceof Promise));
// A query is not a fully-fledged promise, but it does have a `.then()`.
query.then(function (doc) {
// use doc
});
// `.exec()` gives you a fully-fledged promise
var promise = query.exec();
assert.ok(promise instanceof Promise);
promise.then(function (doc) {
// use doc
});
}
您可以使用此庫來增加訂單字段: Mongoose Sequence
var mongoose = require('mongoose');
var AutoIncrement = require('mongoose-sequence')(mongoose);
var ItemSchema = new mongoose.Schema({
text: {
type: String,
required: true
},
key: {
type: String,
required: true
},
status: {
type: String,
required: true
},
order: {
type: Number
}
});
ItemSchema.plugin(AutoIncrement, {id:'order_seq',inc_field: 'order'});
var ItemModel = mongoose.model('Item', ItemSchema);
let newItem1= new ItemModel({
text:'text1',
key:'key1',
status:'A'
});
newItem1.save();
let newItem2= new ItemModel({
text:'text2',
key:'key2',
status:'A'
});
newItem2.save();
let newItem3= new ItemModel({
text:'text3',
key:'key3',
status:'B'
});
newItem3.save();
現在,當您創建新項目時, 訂單字段將由庫遞增:
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