From 92f46ba2af9451a05e197b1d4297488195e00143 Mon Sep 17 00:00:00 2001
From: Jay Caines-Gooby <jay@gooby.org>
Date: Sun, 19 May 2019 20:47:02 +0100
Subject: [PATCH] Fallback to http1.1 if http2 isn't supported
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Fixes #4. Even though the curl command may show that the `--http2` option is available, the version of libcurl that's been linked against might not support it.

Thanks for the tipoff @moeffju 🎉
---
 ttfb | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/ttfb b/ttfb
index 3a4cb1f..4c67910 100755
--- a/ttfb
+++ b/ttfb
@@ -65,6 +65,10 @@ for dependency in curl bc column; do
   which $dependency > /dev/null || (echo "You need to have '$dependency' installed and in your \$PATH" >&2 && exit 1)
 done
 
+# check curl can use http2
+HTTP_VERSION="--http2"
+curl -so /dev/null --http2 https://example.com || HTTP_VERSION="--http1.1"
+
 # Cribbed from https://stackoverflow.com/a/41762669/391826
 median() {
   arr=($(printf '%s\n' "${@}" | sort -n))
@@ -131,7 +135,7 @@ options=()
 options+=(-o /dev/null)
 options+=(-s)
 options+=(-L)
-options+=(--http2)
+options+=($HTTP_VERSION)
 options+=(-H 'Cache-Control: no-cache')
 options+=(-w 'echo DNS lookup: %{time_namelookup} TLS handshake: %{time_appconnect} TTFB including connection: %{time_starttransfer} TTFB: $(echo %{time_starttransfer} - %{time_appconnect} | bc) Total time: %{time_total} \n')
 if [ $DEBUG -eq 1 ]; then