From 23add65058876af3d9c7fb88dffec3f81dd4c87e Mon Sep 17 00:00:00 2001
From: Joakim Reinert <mail@jreinert.com>
Date: Sat, 6 Oct 2018 13:47:48 +0200
Subject: [PATCH] add support for 100-continue in HTTP::Server::Response

---
 spec/std/http/server/server_spec.cr | 9 +++++++++
 src/http/server/response.cr         | 8 ++++++++
 2 files changed, 17 insertions(+)

diff --git a/spec/std/http/server/server_spec.cr b/spec/std/http/server/server_spec.cr
index e57b774a47e2..d851c0fc5d2e 100644
--- a/spec/std/http/server/server_spec.cr
+++ b/spec/std/http/server/server_spec.cr
@@ -216,6 +216,15 @@ module HTTP
         response.respond_with_error("Bad Request", 400)
         io.to_s.should eq("HTTP/1.1 400 Bad Request\r\nContent-Type: text/plain\r\nTransfer-Encoding: chunked\r\n\r\n10\r\n400 Bad Request\n\r\n")
       end
+
+      it "supports 100-continue" do
+        io = MemoryIO.new
+        response = Response.new(io)
+        response.continue
+        response.content_type = "text/html"
+        response << "test"
+        io.to_s.should eq("HTTP/1.1 100 Continue\r\n\r\nHTTP/1.1 200\r\n\r\ntest\r\n")
+      end
     end
   end
 
diff --git a/src/http/server/response.cr b/src/http/server/response.cr
index 615bec1dcaf5..f0b8b97890fc 100644
--- a/src/http/server/response.cr
+++ b/src/http/server/response.cr
@@ -79,6 +79,14 @@ class HTTP::Server
       raise "Can't read from HTTP::Server::Response"
     end
 
+    # Send a 100 Continue response to clients waiting for this before sending
+    # the request body
+    def continue
+      @status_code = 100
+      ensure_headers_written
+      reset
+    end
+
     # Upgrades this response, writing headers and yieling the connection `IO` (a socket) to the given block.
     # The block must invoke `close` afterwards, the server won't do it in this case.
     # This is useful to implement protocol upgrades, such as websockets.