cors middleware for koa2
npm install koa2-cors> it requires node v7.6.0 or higher now
``bash`
npm install --save koa2-cors
`js
var Koa = require('koa');
var cors = require('koa2-cors');
var app = new Koa();
app.use(cors());
`
Configures the Access-Control-Allow-Origin CORS header. expects a string. Can also be set to a function, which takes the ctx as the first parameter.
Configures the Access-Control-Expose-Headers CORS header. Expects a comma-delimited array.
Configures the Access-Control-Max-Age CORS header. Expects a
Number.
Configures the Access-Control-Allow-Credentials CORS header. Expects a Boolean.
Configures the Access-Control-Allow-Methods CORS header. Expects a comma-delimited array , If not specified, default allowMethods is ['GET', 'PUT', 'POST', 'PATCH', 'DELETE', 'HEAD', 'OPTIONS'].
`js
var Koa = require('koa');
var cors = require('koa2-cors');
var app = new Koa();
app.use(cors({
origin: function(ctx) {
if (ctx.url === '/test') {
return false;
}
return '*';
},
exposeHeaders: ['WWW-Authenticate', 'Server-Authorization'],
maxAge: 5,
credentials: true,
allowMethods: ['GET', 'POST', 'DELETE'],
allowHeaders: ['Content-Type', 'Authorization', 'Accept'],
}));
...
``