From 263b4a4fb8ecf10834fc12ccdddf2c267270eabe Mon Sep 17 00:00:00 2001
From: Matthew Kent <matthew@37signals.com>
Date: Sat, 11 Nov 2023 13:03:23 -0800
Subject: [PATCH] Enable aliases for more exotic templating situations.

This is super useful for DRY when configuring a number of roles and you
hit the limits of what's reasonable with ERB.
---
 lib/kamal/configuration.rb | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/kamal/configuration.rb b/lib/kamal/configuration.rb
index fc881c06..87c68dc5 100644
--- a/lib/kamal/configuration.rb
+++ b/lib/kamal/configuration.rb
@@ -25,7 +25,9 @@ class Kamal::Configuration
 
       def load_config_file(file)
         if file.exist?
-          YAML.load(ERB.new(IO.read(file)).result).symbolize_keys
+          # Newer Psych doesn't load aliases by default
+          load_method = YAML.respond_to?(:unsafe_load) ? :unsafe_load : :load
+          YAML.send(load_method, ERB.new(IO.read(file)).result).symbolize_keys
         else
           raise "Configuration file not found in #{file}"
         end