「node-http-proxyで応答ヘッダーを書き換える」のこの回答のおかげで、私はそれを理解することができました。以下のミドルウェアを作成しました。
function rewriteSetCookie(req, res, next) {
var isProxyRequest = req.url.lastIndexOf('/publicPath', 0) === 0;
if (isProxyRequest) {
// we intercept the writeHead function, so that we can exchange headers just before they are written
var oldWriteHead = res.writeHead;
res.writeHead = function () {
var cookie = res.getHeader('Set-Cookie');
if (cookie) {
res.setHeader('Set-Cookie', cookie.map(function(item) {
// Replace paths in all cookies. The simple string/replace approach might be too naive in some cases, so check before you copy&paste before thinking
return item.replace(/\/privatePath/, '/publicPath');
}));
}
oldWriteHead.apply(res, arguments);
};
}
next();
}
参考までに、ミドルウェアの使用方法を確認できるように、完全な構成を以下に示します。
connect: {
server: {
options: {
hostname: 'localhost',
base: 'myBaseDir',
open: true,
middleware: function (connect, options) {
if (!Array.isArray(options.base)) {
options.base = [options.base];
}
// Setup the proxy
var middlewares = [rewriteSetCookie, proxySnippet];
// ^^^^^^^^^^^^^^^^- Here is is used!
// Serve static files.
options.base.forEach(function(base) {
middlewares.push(connect.static(base));
});
// Make directory browse-able.
var directory = options.directory || options.base[options.base.length - 1];
middlewares.push(connect.directory(directory));
return middlewares;
}
},
proxies: [{
context: '/publicPath',
host: 'localhost',
port: 8080,
rewrite: {
'^/publicPath': '/privatePath'
}
}]
}
}