koa学习-jsonp实现

原生koa2实现jsonp

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30 const koa = require('koa');
const app = new koa();
app.use(async (ctx) => {
	// 判断是否为jsonp的请求
	if (ctx.method === 'GET' && ctx.url.split('?')[0] === '/getData.jsonp') {
		// 获取jsonp的callback
		let callbackName = ctx.query.callback || 'callback';
		let returnData = {
			success: true,
			data: {
				text: 'this is a jsonp api',
				time: new Date().getTime()
			}
		} 
		// jsonp的script字符串
		let jsonpStr = `;${callbackName}(${JSON.stringify(returnData)})`;      
		// 用text/javascript，让请求支持跨域获取
		ctx.type = 'text/javascript';
		// 输出jsonp字符串
		ctx.body = jsonpStr
	} else {
		ctx.body = 'hello jsonp';
	}
});
app.listen(3004, () => {
	console.log('[demo] jsonp is starting at port 3004')
});

koa-jsonp中间件实现

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22 const koa = require('koa');
const jsonp = require('koa-jsonp');
const app = new koa();
app.use(jsonp());
app.use(async (ctx) => {
	let returnData = {
		success: true,
		data: {
			text: 'this is a jsonp api',
			time: new Date().getTime(),
		}
	};
	// 直接输出json
	ctx.body = returnData;
});
app.listen(3004, () => {
	console.log('[demo] jsonp is starting at port 3004')
});

参考文档：
koa-note
koa-jsonp