碎碎念ZWS

利用koa简单封装，既可以轻松解决利用第三方接口请求引起的跨域问题，真是简单轻松。

app.js文件节选是这样的：

const Koa = require('koa')
const Router = require('koa-router')
const bodyParser = require('koa-bodyparser')
const feedback = require('./api').feed_back;
const app = new Koa()
const router = new Router()
const port = 90
router.use(bodyParser())
router.post('/api/feedback', async (ctx) => {
	const r = await feedback(ctx.request.body);
	ctx.type = 'text/json';
	ctx.body = r;
})
app.use(router.routes()).use(router.allowedMethods())
const host = `http://localhost:${ port }`
app.listen(port, () => console.log(`server is running on ${ host }`))

api.js文件长这样：

const http = require('http')
const qs = require('querystring')
exports.feed_back = (args,done) => {
    return new Promise( (resolve,reject) => {
        let ctx = qs.stringify(args)
        let options = {
            hostname: 'xxx.com',
            path: '/a/api/b',
            port: '80',
            method: 'POST',
            headers: {
                'Content-Type': 'application/x-www-form-urlencoded'
            }
        }
        const req = http.request(options,(res) => {
            let resData = '';
            res.setEncoding('utf8');
            res.on('data', chunk => {
                resData += chunk;
            })
            res.on('end', () => {
                resolve(resData)
            })
        })
        req.on('error', e => {
            console.log('error:',e.message)
            reject(e.message)
        })
        req.write(ctx)
        req.end();
    } )
}

然后，用postman请求以下，哇！妥妥的返回了数据！