diff --git a/middleware/cors.js b/middleware/cors.js new file mode 100644 index 000000000..de53ad339 --- /dev/null +++ b/middleware/cors.js @@ -0,0 +1,50 @@ +var _ = require('underscore'), + url = require('url'); + +/* + * CORS middleware + * + * options can contains a list of origins + */ +module.exports = function cors(options) { + options = options || { }; + var maxAge = options.maxAge || 60 * 60 * 25 * 5; // 5 days + var origins = options.origins || [ '*' ]; + var allowCredentials = options.allowCredentials || false; // cookies + + return function (req, res, next) { + var requestOrigin = req.headers.origin; + if (!requestOrigin) return next(); + + requestOrigin = url.parse(requestOrigin); + + var hostname = requestOrigin.host.split(':')[0]; // remove any port + var matchedOrigin = _.find(origins, function (o) { return o === '*' || o === hostname }); + if (_.isUndefined(matchedOrigin)) { return res.send(405, 'CORS not allowed from this domain'); } + + // respond back with req.headers.origin which might contain the scheme + res.header('Access-Control-Allow-Origin', req.headers.origin); + + // handle preflighted requests + if (req.method === 'OPTIONS') { + if (req.headers['access-control-request-method']) { + res.header('Access-Control-Allow-Methods', 'GET, PUT, DELETE, POST, OPTIONS'); + } + + if (req.headers['access-control-request-headers']) { + res.header('Access-Control-Allow-Headers', req.headers['access-control-request-headers']); + } + + res.header('Access-Control-Allow-Credentials', allowCredentials); + res.header('Access-Control-Max-Age', maxAge); + + return res.send(200); + } + + if (req.headers['access-control-request-headers']) { + res.header('Access-Control-Allow-Headers', req.headers['access-control-request-headers']); + } + + next(); + } +};