Set headers on the CowboyRequest directly

Cowboy 2.11.0 removed the option of setting cookie headers in `cowboy_req:reply`, `cowboy_req:set_resp_header` or `cowboy_req:set_resp_headers`
To solve this we update the CowboyRequest headers directly, as suggested here: ninenines/cowboy#1624 (comment)

gleam.toml

@@ -14,7 +14,7 @@ links = [
 gleam_stdlib = "~> 0.31"
 gleam_http = "~> 3.0"
 gleam_otp = "~> 0.7"
-cowboy = "~> 2.10.0"
+cowboy = "~> 2.0"
 gleam_erlang = "~> 0.22"
 
 [dev-dependencies]

manifest.toml

@@ -3,8 +3,8 @@
 
 packages = [
   { name = "certifi", version = "2.12.0", build_tools = ["rebar3"], requirements = [], otp_app = "certifi", source = "hex", outer_checksum = "EE68D85DF22E554040CDB4BE100F33873AC6051387BAF6A8F6CE82272340FF1C" },
-  { name = "cowboy", version = "2.10.0", build_tools = ["make", "rebar3"], requirements = ["cowlib", "ranch"], otp_app = "cowboy", source = "hex", outer_checksum = "3AFDCCB7183CC6F143CB14D3CF51FA00E53DB9EC80CDCD525482F5E99BC41D6B" },
-  { name = "cowlib", version = "2.12.1", build_tools = ["make", "rebar3"], requirements = [], otp_app = "cowlib", source = "hex", outer_checksum = "163B73F6367A7341B33C794C4E88E7DBFE6498AC42DCD69EF44C5BC5507C8DB0" },
+  { name = "cowboy", version = "2.12.0", build_tools = ["make", "rebar3"], requirements = ["cowlib", "ranch"], otp_app = "cowboy", source = "hex", outer_checksum = "8A7ABE6D183372CEB21CAA2709BEC928AB2B72E18A3911AA1771639BEF82651E" },
+  { name = "cowlib", version = "2.13.0", build_tools = ["make", "rebar3"], requirements = [], otp_app = "cowlib", source = "hex", outer_checksum = "E1E1284DC3FC030A64B1AD0D8382AE7E99DA46C3246B815318A4B848873800A4" },
   { name = "gleam_erlang", version = "0.24.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_erlang", source = "hex", outer_checksum = "26BDB52E61889F56A291CB34167315780EE4AA20961917314446542C90D1C1A0" },
   { name = "gleam_hackney", version = "1.2.0", build_tools = ["gleam"], requirements = ["gleam_http", "gleam_stdlib", "hackney"], otp_app = "gleam_hackney", source = "hex", outer_checksum = "066B1A55D37DBD61CC72A1C4EDE43C6015B1797FAF3818C16FE476534C7B6505" },
   { name = "gleam_http", version = "3.6.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_http", source = "hex", outer_checksum = "8C07DF9DF8CC7F054C650839A51C30A7D3C26482AC241C899C1CEA86B22DBE51" },
@@ -22,7 +22,7 @@ packages = [
 ]
 
 [requirements]
-cowboy = { version = "~> 2.10.0" }
+cowboy = { version = "~> 2.0" }
 gleam_erlang = { version = "~> 0.22" }
 gleam_hackney = { version = "~> 1.0" }
 gleam_http = { version = "~> 3.0" }

src/gleam/http/cowboy.gleam

@@ -10,14 +10,21 @@ import gleam/bytes_builder.{type BytesBuilder}
 import gleam/dynamic.{type Dynamic}
 import gleam/erlang/process.{type Pid}
 
-type CowboyRequest
+type CowboyRequest 
 
 @external(erlang, "gleam_cowboy_native", "start_link")
 fn erlang_start_link(
   handler: fn(CowboyRequest) -> CowboyRequest,
   port: Int,
 ) -> Result(Pid, Dynamic)
 
+@external(erlang, "gleam_cowboy_native", "set_headers")
+fn erlang_set_headers(headers: Dict(String, Dynamic), request: CowboyRequest) -> CowboyRequest
+
+fn set_headers(headers: Dict(String, Dynamic), request: CowboyRequest) -> CowboyRequest {
+  erlang_set_headers(headers, request)
+}
+
 @external(erlang, "cowboy_req", "reply")
 fn cowboy_reply(
   status: Int,
@@ -120,8 +127,12 @@ fn service_to_handler(
     let status = response.status
 
     let headers = cowboy_format_headers(response.headers)
+    // We set headers directly on the CowboyRequest as we cannot set cookie headers
+    // using cowboy_req:set_resp_headers as of 2.11.0.
+    // https://github.com/ninenines/cowboy/pull/1624#issuecomment-1915324578
+    let request = set_headers(headers, request)
     let body = response.body
-    cowboy_reply(status, headers, body, request)
+    cowboy_reply(status, dict.new(), body, request)
   }
 }
 

src/gleam_cowboy_native.erl

@@ -1,6 +1,6 @@
 -module(gleam_cowboy_native).
 
--export([init/2, start_link/2, read_entire_body/1]).
+-export([init/2, start_link/2, read_entire_body/1, set_headers/2]).
 
 start_link(Handler, Port) ->
     RanchOptions = #{
@@ -29,3 +29,6 @@ read_entire_body(Body, Req0) ->
         {ok, Chunk, Req1} -> {list_to_binary([Body, Chunk]), Req1};
         {more, Chunk, Req1} -> read_entire_body([Body, Chunk], Req1)
     end.
+
+set_headers(Headers, Req) ->
+  Req#{resp_headers => Headers}.

test/gleam/http/cowboy_test.gleam

@@ -1,9 +1,11 @@
 import gleam/http/cowboy
 import gleam/bytes_builder.{type BytesBuilder}
-import gleam/http.{Get, Head, Post}
+import gleam/http.{Get, Head, Post, Http}
 import gleam/http/request.{type Request}
 import gleam/http/response.{type Response}
+import gleam/http/cookie
 import gleam/hackney
+import gleam/list
 
 pub fn echo_service(request: Request(BitArray)) -> Response(BytesBuilder) {
   let body = case request.body {
@@ -12,6 +14,7 @@ pub fn echo_service(request: Request(BitArray)) -> Response(BytesBuilder) {
   }
   response.new(200)
   |> response.prepend_header("made-with", "Gleam")
+  |> response.set_cookie("cookie_name", "cookie_value", cookie.defaults(Http))
   |> response.set_body(body)
 }
 
@@ -87,3 +90,22 @@ pub fn body_is_echoed_on_post_test() {
   let assert Ok("Gleam") = response.get_header(resp, "made-with")
   let assert "Ping" = resp.body
 }
+
+pub fn cookie_headers_are_handled_correctly_test() {
+  let port = 3082
+  let assert Ok(_) = cowboy.start(echo_service, on_port: port)
+
+  let req =
+    request.new()
+    |> request.set_method(Get)
+    |> request.set_host("0.0.0.0")
+    |> request.set_scheme(http.Http)
+    |> request.set_port(port)
+    |> request.set_header("name", "value")
+
+  let assert Ok(resp) = hackney.send(req)
+  let assert 200 = resp.status
+  let assert Ok("Gleam") = response.get_header(resp, "made-with")
+  let cookies = response.get_cookies(resp)
+  let assert True = list.contains(cookies, #("cookie_name", "cookie_value"))
+}