teacher-api-uploadImg/app.js

let koa = require("koa");
// let app=new koa()
// const websockify = require("koa-websocket");

const app = new koa();
let bodyparser = require("koa-bodyparser");
let json = require("koa-json");
let router = require("koa-router")(); //实例化new路由
let cors = require("koa2-cors");
// let verifToken = require("./token.js");
let static = require("koa-static");
const path = require("path");
let multer = require("koa-multer");
let fs = require("fs");

// 配置静态资源
const staticPath = "./public";
app.use(static(path.join(__dirname, staticPath)));

app.use(bodyparser());
app.use(json());
app.use(cors());

// 设置文件存储位置
let storage = multer.diskStorage({
	//设置文件储存位置
	destination: function (req, file, cb) {
		let date = new Date();
		let year = date.getFullYear();
		let month = date.getMonth() + 1;
		let day = date.getDate();
		let dir = "./public/uploads/" + year + month + day;

		if (!fs.existsSync(dir)) {
			fs.mkdirSync(dir, {
				recursive: true,
			});
		}
		cb(null, dir);
	},
	filename: function (req, file, cb) {
		// 设置上传文件名称
		let fileName =
			file.fieldname + "-" + Date.now() + path.extname(file.originalname);
		cb(null, fileName);
	},
});

// 创建multer实例并配置存储引擎
const upload = multer({ storage: storage });

// 上传图片接口
router.post("/img", upload.single("file"), async (ctx) => {
	// console.log(ctx.req.file);
	if (!ctx.req.file) {
		// 如果没有上传文件
		ctx.status = 400; // 设置响应状态码为400，表示请求错误
		ctx.body = "请选择要上传的文件"; // 返回给客户端的提示信息
		return;
	}

	// 检查文件大小
	const fileSize = ctx.req.file.size;
	// console.log(fileSize);
	if (fileSize > 5 * 1024 * 1024) {
		// 如果文件大小超过限制
		ctx.status = 400; // 设置响应状态码为400，表示请求错误
		ctx.body = {   // 返回给客户端的提示信息
			code:400,
			msg:"文件大小超过限制"
		}
		
		// 删除超过限制的文件
		// fs.unlinkSync(ctx.req.file.path);
		fs.unlink(ctx.req.file.path, (err) => {
			if (err) {
			  console.error('文件删除失败', err);
			} else {
			  console.log('文件删除成功');
			}
		  });
		return;
	}
	let path = ctx.req.file.path;
	path = ctx.origin + "" + path.replace("public", "");
	path = path.replace(/\\/g, "/");
	console.log(path);

	ctx.body = path;
});

app.use(router.routes()).use(router.allowedMethods());

// 启动 Koa 应用程序
app.listen(7006, () => {
	console.log("Server is running on port 7006");
});