warp-tls strips out the Host request header

[snoyberg]

Just discovered this due to some buggy behavior in yesod devel, where URLs were misgenerated for TLS connections but generated correctly for non-TLS connections. Take as an example the following print of a Request value for a warp-tls connection:

Request {requestMethod = "GET", httpVersion = HTTP/1.1, rawPathInfo = "/", rawQueryString = "", requestHeaders = [("Host","localhost:3009"),("Connection","keep-alive"),("Accept","text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8"),("Upgrade-Insecure-Requests","1"),("User-Agent","Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2490.86 Safari/537.36"),("Accept-Encoding","gzip, deflate, sdch"),("Accept-Language","en-US,en;q=0.8,he;q=0.6"),("Cookie","_SESSION=SwprbhBIY0Nkf+vIaMIaBXE1cFbWqtLAU5O7CwUmDsrB8YTi+roXGq30tVTLnNCpEqtdmEHMug8TSp9NyV0nJsFt09Q4xcHPPXIAvfxDdj06JeM5LnrH5rSTg5G2JiPPpBSpHzYSpwA=; XSRF-TOKEN=ZdJ5OHPy5K")], isSecure = False, remoteHost = 127.0.0.1:51112, pathInfo = [], queryString = [], requestBody = <IO ByteString>, vault = <Vault>, requestBodyLength = KnownLength 0, requestHeaderHost = Just "localhost:3009", requestHeaderRange = Nothing}

Note that while the requestHeaderHost field is populated, the Host header itself does not appear in the requestHeaders, in contrast with warp itself which populates both. This harms the situation, for example, when reverse proxying.

[snoyberg]

I'm not actually quite sure what's going on in warp-tls right now, @kazu-yamamoto would this be an easy thing for you to fix?

[kazu-yamamoto]

Probably you cut and pasted a wrong example since it has a Host header.

However, I confirmed that WAI apps don't receive Host headers with WarpTLS. This happens only with github code, not with released code.

[kazu-yamamoto]

Never mind. This happens even with warp-tls 3.1.4.

[kazu-yamamoto]

Fixed.

@snoyberg If your problem has gone away with the commit above, please close this issue.

[snoyberg]

Confirmed fixed, thanks!