Merge pull request #707 from basecamp/boot-strategy-min-limit-1

Ensure a minimum limit of 1 for % boot strategy

lib/kamal/configuration/boot.rb

@@ -8,7 +8,7 @@ class Kamal::Configuration::Boot
     limit = @options["limit"]
 
     if limit.to_s.end_with?("%")
-      @host_count * limit.to_i / 100
+      [@host_count * limit.to_i / 100, 1].max
     else
       limit
     end

test/commander_test.rb

@@ -109,6 +109,12 @@ class CommanderTest < ActiveSupport::TestCase
     assert_equal({ in: :groups, limit: 1, wait: 2 }, @kamal.boot_strategy)
   end
 
+  test "percentage-based group strategy limit is at least 1" do
+    configure_with(:deploy_with_low_percentage_boot_strategy)
+
+    assert_equal({ in: :groups, limit: 1, wait: 2 }, @kamal.boot_strategy)
+  end
+
   test "try to match the primary role from a list of specific roles" do
     configure_with(:deploy_primary_web_role_override)
 

test/fixtures/deploy_with_low_percentage_boot_strategy.yml

@@ -0,0 +1,17 @@
+service: app
+image: dhh/app
+servers:
+  web:
+    - "1.1.1.1"
+    - "1.1.1.2"
+  workers:
+    - "1.1.1.3"
+    - "1.1.1.4"
+
+registry:
+  username: user
+  password: pw
+
+boot:
+  limit: 1%
+  wait: 2

test/fixtures/deploy_with_percentage_boot_strategy.yml

@@ -13,5 +13,5 @@ registry:
   password: pw
 
 boot:
-  limit: 25%
+  limit: 1%
   wait: 2