三张表数据格式一样，封装前台API

// 三张表
top250
comingSoon
inTheaters

models/baseDB/db-movies.js 连接数据库

const mongoose = require("mongoose")
var mongodb = mongoose.createConnection( 'mongodb://127.0.0.1:27017/movies', {
    useNewUrlParser: true,
    useUnifiedTopology:true
});
var Schema = mongoose.Schema
module.exports ={
    mongodb,
    Schema
}

models/Schema/MovieSchema.js 封装数据格式

module.exports={
    pic:String,
    title:String,
    slogo:String,
    evaluate:String,
    labels:Array,
    rating:String
}

models/movie.js 封装MovieModel

const {mongodb,Schema} = require("./baseDB/db-movies")
const bean = require("./Schema/MovieSchema")
const MovieSchema = new Schema(bean)
function MovieModel(table){
    return mongodb.model(table,MovieSchema,table)
}
module.exports = MovieModel

routers/api/movie.js 前台API

const router = require("koa-router")()
const MovieModel = require("../../models/movie")
//  /api/movie?m= top250   comingSoon  inTheaters
router.get("/api/movie",async ctx=>{
    var {m} = ctx.query
    try{
        var data = await MovieModel(m).find({}).sort({rating:-1})
        if(data.length){
            ctx.body={
                code:200,
                result:data,
                msg:m
            }
        }else{
            throw new Errow("输入的参数不合法")
        }
    }catch(err){
        ctx.body={
            code:400,
            msg:"请求参数不合法"
        }
    }
})
module.exports = router