From 1b0a2258fcbce9ecc24b9c071af4c1a85cb2950f Mon Sep 17 00:00:00 2001
From: Andrew Kane <andrew@ankane.org>
Date: Wed, 28 Feb 2024 00:25:27 -0800
Subject: [PATCH] Added ignore option

---
 CHANGELOG.md                     |  2 ++
 lib/strong_migrations.rb         |  2 +-
 lib/strong_migrations/checker.rb | 25 +++++++++++++++++++++++++
 test/multiple_databases_test.rb  | 31 +++++++++++++++++++++++++++++++
 4 files changed, 59 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 828c3c7..0eddc54 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,7 @@
 ## 1.7.1 (unreleased)
 
+- Added `ignore` option
+- Added warning for unsupported adapter
 - Updated instructions for removing a column to append to `ignored_columns`
 
 ## 1.7.0 (2024-01-05)
diff --git a/lib/strong_migrations.rb b/lib/strong_migrations.rb
index 9763593..ceac463 100644
--- a/lib/strong_migrations.rb
+++ b/lib/strong_migrations.rb
@@ -29,7 +29,7 @@ class << self
       :target_postgresql_version, :target_mysql_version, :target_mariadb_version,
       :enabled_checks, :lock_timeout, :statement_timeout, :check_down, :target_version,
       :safe_by_default, :target_sql_mode, :lock_timeout_retries, :lock_timeout_retry_delay,
-      :alphabetize_schema
+      :alphabetize_schema, :ignore
     attr_writer :lock_timeout_limit
   end
   self.auto_analyze = false
diff --git a/lib/strong_migrations/checker.rb b/lib/strong_migrations/checker.rb
index ac9ccea..fb5eee4 100644
--- a/lib/strong_migrations/checker.rb
+++ b/lib/strong_migrations/checker.rb
@@ -28,6 +28,7 @@ def self.safety_assured
     end
 
     def perform(method, *args)
+      return if !enabled?
       check_version_supported
       set_timeouts
       check_lock_timeout
@@ -131,6 +132,30 @@ def version_safe?
 
     private
 
+    def enabled?
+      if StrongMigrations.ignore
+        # Active Record 6.0 supports multiple databases
+        # but connection.pool.spec.name always returns "primary"
+        # in migrations with rails db:migrate
+        if ActiveRecord::VERSION::STRING.to_f < 6.1
+          # error class is not shown in db:migrate output so ensure message is descriptive
+          raise StrongMigrations::Error, "StrongMigrations.ignore is not supported for Active Record < 6.1"
+        end
+
+        if StrongMigrations.ignore.map(&:to_s).include?(connection.pool.db_config.name)
+          return false
+        end
+      end
+
+      if adapter.instance_of?(Adapters::AbstractAdapter)
+        # TODO raise error in 2.0
+        # TODO add database name for Active Record 6.1+
+        warn "[strong_migrations] Unsupported adapter: #{connection.adapter_name}. Use StrongMigrations.ignore to silence this warning."
+      end
+
+      true
+    end
+
     def check_version_supported
       return if defined?(@version_checked)
 
diff --git a/test/multiple_databases_test.rb b/test/multiple_databases_test.rb
index a3e780b..247878b 100644
--- a/test/multiple_databases_test.rb
+++ b/test/multiple_databases_test.rb
@@ -40,6 +40,30 @@ def test_target_version_unsupported
     end
   end
 
+  def test_ignore
+    skip unless multiple_dbs?
+
+    with_ignore([:animals]) do
+      with_database(:primary) do
+        assert_unsafe ExecuteArbitrarySQL
+      end
+      with_database(:animals) do
+        assert_safe ExecuteArbitrarySQL
+      end
+    end
+  end
+
+  def test_ignore_unsupported
+    skip if multiple_dbs?
+
+    with_ignore([:animals]) do
+      error = assert_raises(StrongMigrations::Error) do
+        assert_safe ExecuteArbitrarySQL
+      end
+      assert_equal "StrongMigrations.ignore is not supported for Active Record < 6.1", error.message
+    end
+  end
+
   private
 
   def with_database(database, &block)
@@ -59,6 +83,13 @@ def with_database(database, &block)
     ActiveRecord::Base.establish_connection(previous_db_config) if previous_db_config
   end
 
+  def with_ignore(databases)
+    StrongMigrations.ignore = databases
+    yield
+  ensure
+    StrongMigrations.ignore = nil
+  end
+
   def multiple_dbs?
     ActiveRecord::VERSION::STRING.to_f >= 6.1
   end