http-proxy does not support the Expected header: 100-continue

[damianchojna]

If I use http-proxy only as requester, there is a problem with 100-continue.
When we have a response from server with status 100 the requester in http-proxy (proxyReq in web-incoming) do not handle event "continue" and "socket hang up"

[thorntonrp]

The "proxyReq" callback is invoked too late to apply additional headers.

[thorntonrp]

Would it be possible to set request headers after the proxyReq event callback? Or perhaps detect whether Expect: 100-continue is included in the request headers and delay forwarding that header until after the proxyReq event callback has been processed?

[thorntonrp]

As a workaround, I currently set all my headers on the incoming request object inside the HTTP server's "request" event callback. That way they get copied onto the outgoing proxied request before the Expect: 100-continue header is processed for the outgoing request.

[skleeschulte]

This is my workaround, maybe it helps someone:

const proxy = httpProxy.createProxyServer({
    // ...
});

proxy.before('web', 'stream', (req, res, options) => {
    if (req.headers.expect) {
        req.__expectHeader = req.headers.expect;
        delete req.headers.expect;
    }
});

proxy.on('proxyReq', (proxyReq, req, res, options) => {
    // edit proxy request headers with proxyReq.setHeader(...) and proxyReq.removeHeader(...)

    if (req.__expectHeader) {
        proxyReq.setHeader('Expect', req.__expectHeader);
    }
});

proxy.listen(3000);

[tagkiller]

Anything new on this ?