Node.js 如何在流完成管道后呈现响应?
这就是我想要的,服务器是一个文件服务器,当客户端请求某个文件时,它会将该文件流回。我尝试这样做,而不是koi static,但是dest.jpg只包含'notfound' 客户端代码:Node.js 如何在流完成管道后呈现响应?,node.js,koa,Node.js,Koa,这就是我想要的,服务器是一个文件服务器,当客户端请求某个文件时,它会将该文件流回。我尝试这样做,而不是koi static,但是dest.jpg只包含'notfound' 客户端代码: var Koa = require('koa'); var Router = require('koa-router'); const HttpStatus = require('http-status'); const fs = require('fs'); const koaBody = require('k
var Koa = require('koa');
var Router = require('koa-router');
const HttpStatus = require('http-status');
const fs = require('fs');
const koaBody = require('koa-body');
const request = require('request');
const tempSaveFile = fs.createWriteStream('dest.jpg');
const writeStream = request.post('http://localhost:3456/getfile/src.jpg').pipe(tempSaveFile);
writeStream.on('finish', () => {
tempSaveFile.end();
console.log('Upload successful! ');
});
服务器代码:
var Koa = require('koa');
var Router = require('koa-router');
const HttpStatus = require('http-status');
const fs = require('fs');
const koaBody = require('koa-body');
var app = new Koa();
var router = new Router();
const serve = require('koa-static');
router
.post([`/getfile/:fileName`],
(ctx) => {
const { params: { fileName } } = ctx;
console.error(`------- server will return ${fileName} --------`);
const readStream = fs.createReadStream(fileName).pipe(ctx.res);
readStream.on('finish', () => {
console.error('---- server finished stream ----');
ctx.status = HttpStatus.OK;
});
})
app.use(router.routes());
app.use(router.allowedMethods());
app.listen(3456);
当我将服务器更改为使用koa static时,客户端可以成功地获取文件,did diff,外观相同
我怀疑服务器在完成之前返回得太快,但另一篇帖子说这是等待管道完成的方式。
有什么建议吗?谢谢 好的,我添加了异步,现在可以工作了
const multiparty = require('multiparty');
const multer = require('koa-multer');
const request = require('request');
var app = new Koa();
var router = new Router();
const serve = require('koa-static');
const streamEnd = fd => new Promise((resolve, reject) => {
fd.on('end', () => {console.error('-- 51 --'); resolve(51); });
fd.on('finish', () => {console.error('-- 53 --'); resolve(53); });
fd.on('error', reject);
});
router
.get([`/getfile/:fileName`],
async (ctx) => {
const { params: { fileName } } = ctx;
console.error(`------- server will return ${fileName} --------`);
if (fs.existsSync(fileName)) {
const readStream = fs.createReadStream(fileName).pipe(ctx.res);
await streamEnd(readStream);
ctx.status = HttpStatus.OK;
} else {
console.error(`File ${fileName} doesnot exist`);
ctx.status = HttpStatus.INTERNAL_SERVER_ERROR;
}
})
app.use(serve('./customer'));
app.use(router.routes());
app.use(router.allowedMethods());
app.listen(3456);
我想我错过了等待的承诺。