后端小白的我，是如何成功搭建 express+mongodb 的简洁博客网站后端的

// modules
const createError = require('http-errors');
const express = require('express');
const path = require('path');
const cookieParser = require('cookie-parser');
const logger = require('morgan');
const session = require('express-session');
// import 等语法要用到 babel 支持
require('babel-register');
const app = express();
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'ejs');
app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(express.static(path.join(__dirname, 'public')));
app.use(cookieParser('blog_node_cookie'));
app.use(
    session({
        secret: 'blog_node_cookie',
        name: 'session_id', //# 在浏览器中生成cookie的名称key，默认是connect.sid
        resave: true,
        saveUninitialized: true,
        cookie: { maxAge: 60 * 1000 * 30, httpOnly: true }, //过期时间
    }),
);
const mongodb = require('./core/mongodb');
// data server
mongodb.connect();
//将路由文件引入
const route = require('./routes/index');
//初始化所有路由
route(app);
// catch 404 and forward to error handler
app.use(function(req, res, next) {
    next(createError(404));
});
// error handler
app.use(function(err, req, res, next) {
    // set locals, only providing error in development
    res.locals.message = err.message;
    res.locals.error = req.app.get('env') === 'development' ? err : {};
    // render the error page
    res.status(err.status || 500);
    res.render('error');
});
module.exports = app;

/**
 * Mongoose module.
 * @file 数据库模块
 * @module core/mongoose
 * @author  biaochenxuying <https://github.com/biaochenxuying>
 */
const consola = require('consola')
const CONFIG = require('../app.config.js')
const mongoose = require('mongoose')
const autoIncrement = require('mongoose-auto-increment')
// remove DeprecationWarning
mongoose.set('useFindAndModify', false)
// mongoose Promise
mongoose.Promise = global.Promise
// mongoose
exports.mongoose = mongoose
// connect
exports.connect = () => {
    // 连接数据库
    mongoose.connect(CONFIG.MONGODB.uri, {
        useCreateIndex: true,
        useNewUrlParser: true,
        promiseLibrary: global.Promise
    })
    // 连接错误
    mongoose.connection.on('error', error => {
        consola.warn('数据库连接失败!', error)
    })
    // 连接成功
    mongoose.connection.once('open', () => {
        consola.ready('数据库连接成功!')
    })
    // 自增 ID 初始化
    autoIncrement.initialize(mongoose.connection)
    // 返回实例
    return mongoose
}

/**
 * User model module.
 * @file 权限和用户数据模型
 * @module model/user
 * @author biaochenxuying <https://github.com/biaochenxuying>
 */
const crypto = require('crypto');
const { argv } = require('yargs');
const { mongoose } = require('../core/mongodb.js');
const autoIncrement = require('mongoose-auto-increment');
const adminSchema = new mongoose.Schema({
    // 名字
    name: { type: String, required: true, default: '' },
    // 用户类型 0：博主 1：其他用户
    type: { type: Number, default: 1 },
    // 手机
    phone: { type: String, default: '' },
    //封面
    img_url: { type: String, default: '' },
    // 邮箱
    email: { type: String, required: true, validate: /\w[-\w.+]*@([A-Za-z0-9][-A-Za-z0-9]+\.)+[A-Za-z]{2,14}/ },
    // 个人介绍
    introduce: { type: String, default: '' },
    // 头像
    avatar: { type: String, default: 'user' },
    // 密码
    password: {
        type: String,
        required: true,
        default: crypto
            .createHash('md5')
            .update(argv.auth_default_password || 'root')
            .digest('hex'),
    },
    // 创建日期
    create_time: { type: Date, default: Date.now },
    // 最后修改日期
    update_time: { type: Date, default: Date.now },
});
// 自增 ID 插件配置
adminSchema.plugin(autoIncrement.plugin, {
    model: 'User',
    field: 'id',
    startAt: 1,
    incrementBy: 1,
});
module.exports = mongoose.model('User', adminSchema);

/**
* Article model module.
* @file 文章数据模型
* @module model/article
* @author biaochenxuying <https://github.com/biaochenxuying>
*/
const { mongoose } = require('../core/mongodb.js');
const autoIncrement = require('mongoose-auto-increment');
// 文章模型
const articleSchema = new mongoose.Schema({
    // 文章标题
    title: { type: String, required: true, validate: /\S+/ },
    // 文章关键字（SEO）
    keyword: [{ type: String, default: '' }],
    // 作者
    author: { type: String, required: true, validate: /\S+/ },
    // 文章描述
    desc: { type: String, default: '' },
    // 文章内容
    content: { type: String, required: true, validate: /\S+/ },
    // 字数
    numbers: { type: String, default: 0 },
    // 封面图
    img_url: { type: String, default: 'https://upload-images.jianshu.io/upload_images/12890819-80fa7517ab3f2783.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240' },
    // 文章类型 => 1: 普通文章，2: 简历，3: 管理员介绍
    type: { type: Number, default: 1 },
    // 文章发布状态 => 0 草稿，1 已发布
    state: { type: Number, default: 1 },
    // 文章转载状态 => 0 原创，1 转载，2 混合
    origin: { type: Number, default: 0 },
    // 文章标签
    tags: [{ type: mongoose.Schema.Types.ObjectId, ref: 'Tag', required: true }],
    comments: [{ type: mongoose.Schema.Types.ObjectId, ref: 'Comment', required: true }],
    // 文章分类
    category: [{ type: mongoose.Schema.Types.ObjectId, ref: 'Category', required: true }],
    // 点赞的用户
    like_users: [
        {
            // 用户id
            id: { type: mongoose.Schema.Types.ObjectId },
            // 名字
            name: { type: String, required: true, default: '' },
            // 用户类型 0：博主 1：其他用户
            type: { type: Number, default: 1 },
            // 个人介绍
            introduce: { type: String, default: '' },
            // 头像
            avatar: { type: String, default: 'user' },
            // 创建日期
            create_time: { type: Date, default: Date.now },
        },
    ],
    // 其他元信息
    meta: {
        views: { type: Number, default: 0 },
        likes: { type: Number, default: 0 },
        comments: { type: Number, default: 0 },
    },
    // 创建日期
    create_time: { type: Date, default: Date.now },
    // 最后修改日期
    update_time: { type: Date, default: Date.now },
});
// 自增 ID 插件配置
articleSchema.plugin(autoIncrement.plugin, {
    model: 'Article',
    field: 'id',
    startAt: 1,
    incrementBy: 1,
});
// 文章模型
module.exports = mongoose.model('Article', articleSchema);

/**
* Comment model module.
* @file 评论数据模型
* @module model/comment
* @author biaochenxuying <https://github.com/biaochenxuying>
*/
const { mongoose } = require('../core/mongodb.js');
const autoIncrement = require('mongoose-auto-increment');
// 评论模型
const commentSchema = new mongoose.Schema({
    // 评论所在的文章 id
    article_id: { type: mongoose.Schema.Types.ObjectId, required: true },
    // content
    content: { type: String, required: true, validate: /\S+/ },
    // 是否置顶
    is_top: { type: Boolean, default: false },
    // 被赞数
    likes: { type: Number, default: 0 },
    user_id: { type: mongoose.Schema.Types.ObjectId, ref: 'User', required: true },
    // 父评论的用户信息
    user: {
        // 用户id
        user_id: { type: mongoose.Schema.Types.ObjectId },
        // 名字
        name: { type: String, required: true, default: '' },
        // 用户类型 0：博主 1：其他用户
        type: { type: Number, default: 1 },
        // 头像
        avatar: { type: String, default: 'user' },
    },
    // 第三者评论
    other_comments: [
        {
            user: {
                id: { type: mongoose.Schema.Types.ObjectId },
                // 名字
                name: { type: String, required: true, default: '' },
                // 用户类型 0：博主 1：其他用户
                type: { type: Number, default: 1 },
            },
            // content
            content: { type: String, required: true, validate: /\S+/ },
            // 状态 => 0 待审核 / 1 通过正常 / -1 已删除 / -2 垃圾评论
            state: { type: Number, default: 1 },
            // 创建日期
            create_time: { type: Date, default: Date.now },
        },
    ],
    // 状态 => 0 待审核 / 1 通过正常 / -1 已删除 / -2 垃圾评论
    state: { type: Number, default: 1 },
    // 创建日期
    create_time: { type: Date, default: Date.now },
    // 最后修改日期
    update_time: { type: Date, default: Date.now },
});
// 自增 ID 插件配置
commentSchema.plugin(autoIncrement.plugin, {
    model: 'Comment',
    field: 'id',
    startAt: 1,
    incrementBy: 1,
});
// 标签模型
module.exports = mongoose.model('Comment', commentSchema);

/*
*所有的路由接口
*/
const user = require('./user');
const article = require('./article');
const comment = require('./comment');
const message = require('./message');
const tag = require('./tag');
const link = require('./link');
const category = require('./category');
const timeAxis = require('./timeAxis');
module.exports = app => {
    app.post('/login', user.login);
    app.post('/logout', user.logout);
    app.post('/loginAdmin', user.loginAdmin);
    app.post('/register', user.register);
    app.post('/delUser', user.delUser);
    app.get('/currentUser', user.currentUser);
    app.get('/getUserList', user.getUserList);
    app.post('/addComment', comment.addComment);
    app.post('/addThirdComment', comment.addThirdComment);
    app.post('/changeComment', comment.changeComment);
    app.post('/changeThirdComment', comment.changeThirdComment);
    app.get('/getCommentList', comment.getCommentList);
    app.post('/addArticle', article.addArticle);
    app.post('/updateArticle', article.updateArticle);
    app.post('/delArticle', article.delArticle);
    app.get('/getArticleList', article.getArticleList);
    app.get('/getArticleListAdmin', article.getArticleListAdmin);
    app.post('/getArticleDetail', article.getArticleDetail);
    app.post('/likeArticle', article.likeArticle);
    app.post('/addTag', tag.addTag);
    app.post('/delTag', tag.delTag);
    app.get('/getTagList', tag.getTagList);
    app.post('/addMessage', message.addMessage);
    app.post('/addReplyMessage', message.addReplyMessage);
    app.post('/delMessage', message.delMessage);
    app.post('/getMessageDetail', message.getMessageDetail);
    app.get('/getMessageList', message.getMessageList);
    app.post('/addLink', link.addLink);
    app.post('/updateLink', link.updateLink);
    app.post('/delLink', link.delLink);
    app.get('/getLinkList', link.getLinkList);
    app.post('/addCategory', category.addCategory);
    app.post('/delCategory', category.delCategory);
    app.get('/getCategoryList', category.getCategoryList);
    app.post('/addTimeAxis', timeAxis.addTimeAxis);
    app.post('/updateTimeAxis', timeAxis.updateTimeAxis);
    app.post('/delTimeAxis', timeAxis.delTimeAxis);
    app.get('/getTimeAxisList', timeAxis.getTimeAxisList);
    app.post('/getTimeAxisDetail', timeAxis.getTimeAxisDetail);
};

import { responseClient } from '../util/util';
import Comment from '../models/comment';
import User from '../models/user';
import Article from '../models/article';
//获取全部评论
exports.getCommentList = (req, res) => {
    let keyword = req.query.keyword || null;
    let comment_id = req.query.comment_id || null;
    let pageNum = parseInt(req.query.pageNum) || 1;
    let pageSize = parseInt(req.query.pageSize) || 10;
    let conditions = {};
    if (comment_id) {
        if (keyword) {
            const reg = new RegExp(keyword, 'i'); //不区分大小写
            conditions = {
                _id: comment_id,
                content: { $regex: reg },
            };
        } else {
            conditions = {
                _id: comment_id,
            };
        }
    } else {
        if (keyword) {
            const reg = new RegExp(keyword, 'i'); //不区分大小写
            conditions = {
                content: { $regex: reg },
            };
        }
    }
    let skip = pageNum - 1 < 0 ? 0 : (pageNum - 1) * pageSize;
    let responseData = {
        count: 0,
        list: [],
    };
    Comment.countDocuments(conditions, (err, count) => {
        if (err) {
            console.error('Error:' + err);
        } else {
            responseData.count = count;
            // 待返回的字段
            let fields = {
                article_id: 1,
                content: 1,
                is_top: 1,
                likes: 1,
                user_id: 1,
                user: 1,
                other_comments: 1,
                state: 1,
                create_time: 1,
                update_time: 1,
            };
            let options = {
                skip: skip,
                limit: pageSize,
                sort: { create_time: -1 },
            };
            Comment.find(conditions, fields, options, (error, result) => {
                if (err) {
                    console.error('Error:' + error);
                    // throw error;
                } else {
                    responseData.list = result;
                    responseClient(res, 200, 0, '操作成功！', responseData);
                }
            });
        }
    });
};
// 添加一级评论
exports.addComment = (req, res) => {
    if (!req.session.userInfo) {
        responseClient(res, 200, 1, '您还没登录,或者登录信息已过期，请重新登录！');
        return;
    }
    let { article_id, user_id, content } = req.body;
    User.findById({
        _id: user_id,
    })
        .then(result => {
            // console.log('result :', result);
            if (result) {
                let userInfo = {
                    user_id: result._id,
                    name: result.name,
                    type: result.type,
                    avatar: result.avatar,
                };
                let comment = new Comment({
                    article_id: article_id,
                    content: content,
                    user_id: user_id,
                    user: userInfo,
                });
                comment
                    .save()
                    .then(commentResult => {
                        Article.findOne({ _id: article_id }, (errors, data) => {
                            if (errors) {
                                console.error('Error:' + errors);
                                // throw errors;
                            } else {
                                data.comments.push(commentResult._id);
                                data.meta.comments = data.meta.comments + 1;
                                Article.updateOne({ _id: article_id }, { comments: data.comments, meta: data.meta })
                                    .then(result => {
                                        responseClient(res, 200, 0, '操作成功 ！', commentResult);
                                    })
                                    .catch(err => {
                                        console.error('err :', err);
                                        throw err;
                                    });
                            }
                        });
                    })
                    .catch(err2 => {
                        console.error('err :', err2);
                        throw err2;
                    });
            } else {
                responseClient(res, 200, 1, '用户不存在');
            }
        })
        .catch(error => {
            console.error('error :', error);
            responseClient(res);
        });
};
// 添加第三者评论
exports.addThirdComment = (req, res) => {
    if (!req.session.userInfo) {
        responseClient(res, 200, 1, '您还没登录,或者登录信息已过期，请重新登录！');
        return;
    }
    let { article_id, comment_id, user_id, content } = req.body;
    Comment.findById({
        _id: comment_id,
    })
        .then(commentResult => {
            User.findById({
                _id: user_id,
            })
                .then(userResult => {
                    if (userResult) {
                        let userInfo = {
                            user_id: userResult._id,
                            name: userResult.name,
                            type: userResult.type,
                            avatar: userResult.avatar,
                        };
                        let item = {
                            user: userInfo,
                            content: content,
                        };
                        commentResult.other_comments.push(item);
                        Comment.updateOne(
                            { _id: comment_id },
                            {
                                other_comments: commentResult,
                            },
                        )
                            .then(result => {
                                responseClient(res, 200, 0, '操作成功', result);
                                Article.findOne({ _id: article_id }, (errors, data) => {
                                    if (errors) {
                                        console.error('Error:' + errors);
                                        // throw errors;
                                    } else {
                                        data.meta.comments = data.meta.comments + 1;
                                        Article.updateOne({ _id: article_id }, { meta: data.meta })
                                            .then(result => {
                                                // console.log('result :', result);
                                                responseClient(res, 200, 0, '操作成功 ！', result);
                                            })
                                            .catch(err => {
                                                console.log('err :', err);
                                                throw err;
                                            });
                                    }
                                });
                            })
                            .catch(err1 => {
                                console.error('err1:', err1);
                                responseClient(res);
                            });
                    } else {
                        responseClient(res, 200, 1, '用户不存在');
                    }
                })
                .catch(error => {
                    console.error('error :', error);
                    responseClient(res);
                });
        })
        .catch(error2 => {
            console.error('error2 :', error2);
            responseClient(res);
        });
};
// 管理一级评论
exports.changeComment = (req, res) => {
    if (!req.session.userInfo) {
        responseClient(res, 200, 1, '您还没登录,或者登录信息已过期，请重新登录！');
        return;
    }
    let { id, state } = req.body;
    Comment.updateOne(
        { _id: id },
        {
            state: Number(state),
        },
    )
        .then(result => {
            responseClient(res, 200, 0, '操作成功', result);
        })
        .catch(err => {
            console.error('err:', err);
            responseClient(res);
        });
};
// 管理第三者评论
exports.changeThirdComment = (req, res) => {
    if (!req.session.userInfo) {
        responseClient(res, 200, 1, '您还没登录,或者登录信息已过期，请重新登录！');
        return;
    }
    let { comment_id, state, index } = req.body;
    Comment.findById({
        _id: comment_id,
    })
        .then(commentResult => {
            let i = index ? Number(index) : 0;
            if (commentResult.other_comments.length) {
                commentResult.other_comments[i].state = Number(state);
                Comment.updateOne(
                    { _id: comment_id },
                    {
                        other_comments: commentResult,
                    },
                )
                    .then(result => {
                        responseClient(res, 200, 0, '操作成功', result);
                    })
                    .catch(err1 => {
                        console.error('err1:', err1);
                        responseClient(res);
                    });
            } else {
                responseClient(res, 200, 1, '第三方评论不存在！', result);
            }
        })
        .catch(error2 => {
            console.log('error2 :', error2);
            responseClient(res);
        });
};

# install dependencies
npm install 
# serve with hot reload at localhost: 3000
npm start
# build for production with minification