Misbehavior in the presence of HTTP 103 early hints

[thomasjm]

Initially I filed fpco/http-reverse-proxy#44, but then I decided to test if http-client itself works properly in the presence of HTTP 103 early hints, and it seems it does not.

I added another repro alongside my existing one, so you can check it as follows. The meat of it is here.

cd $(mktemp -d)
git clone [email protected]:codedownio/http-reverse-proxy.git --branch http-103-early-hints-repro
npm install && npm run start # Starts a test Node.js server

# Now switch to the same folder in another terminal and do
stack run client-test

This will use http-client to make a normal request, as well as an early-hints request.

Normal request output

Doing an HTTP request to http://localhost:3005/simple
The status code was: 200
Full response: Response {responseStatus = Status {statusCode = 200, statusMessage = "OK"}, responseVersion = HTTP/1.1, responseHeaders = [("X-Powered-By","Express"),("Content-Type","text/html; charset=utf-8"),("Content-Length","16"),("ETag","W/\"10-uViC3pa4b5/U2h5JkCXIHUyMvk0\""),("Date","Wed, 22 Nov 2023 07:25:23 GMT"),("Connection","keep-alive"),("Keep-Alive","timeout=5")], responseBody = "Simple response!", responseCookieJar = CJ {expose = []}, responseClose' = ResponseClose}
"Simple response!"

Early hints request output

Doing an HTTP request to http://localhost:3005/early_hints
The status code was: 103
Full response: Response {responseStatus = Status {statusCode = 103, statusMessage = "Early Hints"}, responseVersion = HTTP/1.1, responseHeaders = [("Link","</some-file.js>")], responseBody = "", responseCookieJar = CJ {expose = []}, responseClose' = ResponseClose}
""

It seems that http-client sees the HTTP 103 status line and thinks it's at the end of the request. It gets the headers, but doesn't proceed to get the final status code or the response body.

[thomasjm]

Resolved by #524.