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Scaffold back end project created

Egg.js project initialization

Create a folder HZW -dev-cli-server and go to the folder

Run the following command to use the default values.

npm init egg --type=simple
npm i
npm run dev
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It will then generate a link for you

The following screen will appear when you open it, indicating that an egg program has been successfully started.

Add the API

The new app/controller/project. Js

// app\controller\project.js
'use strict';

const Controller = require('egg').Controller;

class HomeController extends Controller {
  async index() {
    const { ctx } = this;
    ctx.body = [{ a: 1.b: 2}]; }}module.exports = HomeController;
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Modify the app \ router. Js

// app\router.js
'use strict';

/ * * *@param {Egg.Application} app - egg application
 */
module.exports = app= > {
  const { router, controller } = app;
  router.get('/', controller.home.index);
  router.get('/project', controller.project.index);
};

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Go to http://127.0.0.1:7001/project

An API has been added.

Then clean up the project, get rid of the stuff, and change the code a little bit.

// app\controller\project.js
const Controller = require('egg').Controller;

class HomeController extends Controller {
  async getTemplate() {
    const { ctx } = this;
    ctx.body = 'get template'; }}module.exports = HomeController;
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// app\router.js
module.exports = app= > {
  const { router, controller } = app;
  router.get('/project/gettemplate', controller.project.getTemplate);
};
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Modify the Hosts

You can use the switchHosts software to manage local hosts

Just add this line and you can use the domain name to access the local development environment

Now we go to http://www.duwanyu.com:7001/project/gettemplate

The result is the same

How to use mongodb

Local mongodb Installation

Download from 👉👉

Download all the default installation can be.

Find the bin directory and run mongo.exe. If the following screen appears, the startup is successful.

Enter http://localhost:27017/ in the browser

The following interface appears:

Mongo. exe fails to open for the second time, create a new data/db directory in the root directory of disk D, then run.\ mongod-dbpath D :\data\db, the problem is solved.

mongodb compass

Website after download and install, by directing: / / 127.0.0.1:27017 connected to the local database

Add a database using the visualization tool, create a collection, and then add a piece of data.

You can see that the database and collection are already created, and add data using the Add Data button

A single piece of data is inserted.

Command line operation

I added mongod. Exe directly to Windows Terminal, so that you can quickly use the command line to operate the database.

• Show DBS: Lists all databases.
• use hzw-cli-dev: switch to thehzw-cli-devThe database
• Db: indicates the current database
• Show Collections: Lists all collections under the current database
• Db.template.find () : Queries data in the collection

Egg.js connects to the local mongodb database

Import the @pick-star/cli-mongodb tool and modify the corresponding code

npm i -S @pick-star/cli-mongodb
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app\utils\mongodb.js

const Mongodb = require('@pick-star/cli-mongodb');

const { mongodbDbName, mongodbUrl } = require('.. /.. /config/db');

// Generate an encapsulated mongodb instance to manipulate the database
function mongo() {
  return new Mongodb(mongodbUrl, mongodbDbName);
}

module.exports = mongo;
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config\db.js

// Database address
const mongodbUrl = 'mongo: / / 127.0.0.1:27017';
// Database name
const mongodbDbName = 'hzw-cli-dev';

module.exports = {
  mongodbUrl,
  mongodbDbName,
};
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app\controller\project.js

const Controller = require('egg').Controller;

const mongo = require('.. /utils/mongodb') ();class ProjectController extends Controller {
  async getTemplate() {
    const { ctx } = this;
    // Query the template collection
    const data = await mongo.query('template'); ctx.body = data; }}module.exports = ProjectController;
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Ok, the results are in.