From a0e61ae5c6006970ea328e6bde595c54a398c1bf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=2E=20K=C3=A4rkk=C3=A4inen?=
 <tronic@users.noreply.github.com>
Date: Mon, 9 Mar 2020 14:35:06 +0200
Subject: [PATCH] 35 % speedup in HTTP/1.1 response formatting (not so much
 overall effect).

---
 sanic/headers.py  | 23 +++++++++++++----------
 sanic/http.py     |  2 +-
 sanic/response.py |  2 +-
 3 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/sanic/headers.py b/sanic/headers.py
index 74a797ee..3dc729a9 100644
--- a/sanic/headers.py
+++ b/sanic/headers.py
@@ -175,14 +175,17 @@ def parse_host(host: str) -> Tuple[Optional[str], Optional[int]]:
     host, port = m.groups()
     return host.lower(), int(port) if port is not None else None
 
+_HTTP1_STATUSLINES = [
+    b"HTTP/1.1 %d %b\r\n" % (status, STATUS_CODES.get(status, b"UNKNOWN"))
+    for status in range(1000)
+]
 
-def format_http1_response(
-    status: int, headers: HeaderBytesIterable, body=b""
-) -> bytes:
-    """Format a full HTTP/1.1 response."""
-    return b"HTTP/1.1 %d %b\r\n%b\r\n%b" % (
-        status,
-        STATUS_CODES.get(status, b"UNKNOWN"),
-        b"".join(b"%b: %b\r\n" % h for h in headers),
-        body,
-    )
+def format_http1_response(status: int, headers: HeaderBytesIterable) -> bytes:
+    """Format a HTTP/1.1 response header."""
+    # Note: benchmarks show that here bytes concat is faster than bytearray,
+    # b"".join() or %-formatting. %timeit any changes you make.
+    ret = _HTTP1_STATUSLINES[status]
+    for h in headers:
+        ret += b"%b: %b\r\n" % h
+    ret += b"\r\n"
+    return ret
diff --git a/sanic/http.py b/sanic/http.py
index 29821b07..5be70957 100644
--- a/sanic/http.py
+++ b/sanic/http.py
@@ -222,7 +222,7 @@ class Http:
             data = b""
             self.response_func = self.head_response_ignored
         headers["connection"] = "keep-alive" if self.keep_alive else "close"
-        ret = format_http1_response(status, res.processed_headers, data)
+        ret = format_http1_response(status, res.processed_headers) + data
         # Send a 100-continue if expected and not Expectation Failed
         if self.expecting_continue:
             self.expecting_continue = False
diff --git a/sanic/response.py b/sanic/response.py
index 47f04b39..c07f38d7 100644
--- a/sanic/response.py
+++ b/sanic/response.py
@@ -47,7 +47,7 @@ class BaseHTTPResponse:
                 headers += (b"content-type", self.content_type.encode()),
         for name, value in self.headers.items():
             name = f"{name}".lower()
-            if name.lower() == "set-cookie":
+            if name == "set-cookie":
                 cookies[value.key] = value
             else:
                 headers += (name.encode("ascii"), f"{value}".encode()),