From b0ae75251272a05e832f52c73ab197979b4ba578 Mon Sep 17 00:00:00 2001
From: Alex Piechowski <alex@piechowski.io>
Date: Tue, 8 Feb 2022 20:35:34 -0600
Subject: [PATCH] Change ForceSSLHandler#secure? to use == instead of regex
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It's more clear and 52x faster in majority of scenarios (matches) and
24x faster on redirects (mismatches)

It also does remove case insensitive searching, but it discussion on the
PR #1662 stated this should be okay functionality to change

Benchmark:

```crystal
require "benchmark"

puts "Matches"
Benchmark.ips do |x|
  x.report("String ==") do
    "https" == "https"
  end

  x.report("!! String =~ /https/i") do
    !!("https" =~ /https/i)
  end
end

puts "\n\nMismatches"
Benchmark.ips do |x|
  x.report("String == mismatch") do
    "http" == "https"
  end

  x.report("!! String =~ /https/i mismatch") do
    !!("http" =~ /https/i)
  end
end
```

```plaintext
➜  tmp crystal build --release downcase-includes-vs-regex.cr && ./downcase-includes-vs-regex
Matches
            String == 897.53M (  1.11ns) (± 6.76%)   0.0B/op        fastest
!! String =~ /https/i  17.13M ( 58.36ns) (±16.32%)  16.0B/op  52.38× slower

Mismatches
            String == mismatch 881.32M (  1.13ns) (± 8.78%)   0.0B/op        fastest
!! String =~ /https/i mismatch  36.42M ( 27.46ns) (± 1.47%)  16.0B/op  24.20× slower
```
---
 src/lucky/force_ssl_handler.cr | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/lucky/force_ssl_handler.cr b/src/lucky/force_ssl_handler.cr
index e3d186603..3abf7654f 100644
--- a/src/lucky/force_ssl_handler.cr
+++ b/src/lucky/force_ssl_handler.cr
@@ -48,7 +48,7 @@ class Lucky::ForceSSLHandler
   end
 
   private def secure?(context) : Bool
-    !!(context.request.headers["X-Forwarded-Proto"]? =~ /https/i)
+    context.request.headers["X-Forwarded-Proto"]? == "https"
   end
 
   private def redirect_to_secure_version(context : HTTP::Server::Context)