From 5b694a081412397b8f5491ffa016d89dde9786fd Mon Sep 17 00:00:00 2001
From: Matthew Kent <matthew@37signals.com>
Date: Tue, 21 Nov 2023 15:44:59 -0800
Subject: [PATCH] Support passing a short-sha version for rollback when using
 git.

Only for emergencies.
---
 lib/kamal/cli/main.rb |  2 +-
 lib/kamal/git.rb      | 10 ++++++++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/lib/kamal/cli/main.rb b/lib/kamal/cli/main.rb
index 6adc36fe..d602b4a1 100644
--- a/lib/kamal/cli/main.rb
+++ b/lib/kamal/cli/main.rb
@@ -93,7 +93,7 @@ class Kamal::Cli::Main < Kamal::Cli::Base
       mutating do
         invoke_options = deploy_options
 
-        KAMAL.config.version = version
+        KAMAL.config.version = Kamal::Git.used? ? Kamal::Git.resolve_revision(version) : version
         old_version = nil
 
         if container_available?(version)
diff --git a/lib/kamal/git.rb b/lib/kamal/git.rb
index 8d59827a..ebe3d4d2 100644
--- a/lib/kamal/git.rb
+++ b/lib/kamal/git.rb
@@ -13,6 +13,16 @@ module Kamal::Git
     `git rev-parse HEAD`.strip
   end
 
+  # Attempt to convert a short -> long git sha, or return the original
+  def resolve_revision(revision)
+    resolved_rev = `git rev-parse -q --verify #{revision}`.strip
+    if resolved_rev.empty?
+      revision
+    else
+      resolved_rev
+    end
+  end
+
   def uncommitted_changes
     `git status --porcelain`.strip
   end