Make lifecycle_type non-nullable on apps, droplets, and builds

Author: WeiQuan0605

db/migrations/20260825120100_make_lifecycle_type_non_nullable.rb

@@ -0,0 +1,13 @@
+Sequel.migration do
+  up do
+    alter_table(:apps)     { set_column_not_null :lifecycle_type }
+    alter_table(:droplets) { set_column_not_null :lifecycle_type }
+    alter_table(:builds)   { set_column_not_null :lifecycle_type }
+  end
+
+  down do
+    alter_table(:apps)     { set_column_allow_null :lifecycle_type }
+    alter_table(:droplets) { set_column_allow_null :lifecycle_type }
+    alter_table(:builds)   { set_column_allow_null :lifecycle_type }
+  end
+end

spec/migrations/20260825120100_make_lifecycle_type_non_nullable_spec.rb

@@ -0,0 +1,30 @@
+require 'spec_helper'
+require 'migrations/helpers/migration_shared_context'
+
+RSpec.describe 'migration to make lifecycle_type non-nullable on apps, droplets, and builds', isolation: :truncation, type: :migration do
+  include_context 'migration' do
+    let(:migration_filename) { '20260825120100_make_lifecycle_type_non_nullable.rb' }
+  end
+
+  before do
+    db[:apps].insert(guid: 'app-guid', lifecycle_type: 'buildpack')
+    db[:droplets].insert(guid: 'droplet-guid', state: 'STAGED', lifecycle_type: 'buildpack')
+    db[:builds].insert(guid: 'build-guid', lifecycle_type: 'buildpack')
+  end
+
+  it 'makes lifecycle_type non-nullable, is reversible, and is idempotent' do
+    Sequel::Migrator.run(db, migrations_path, target: current_migration_index, allow_missing_migration_files: true)
+
+    expect(db.schema(:apps).find { |col| col[0] == :lifecycle_type }[1][:allow_null]).to be false
+    expect(db.schema(:droplets).find { |col| col[0] == :lifecycle_type }[1][:allow_null]).to be false
+    expect(db.schema(:builds).find { |col| col[0] == :lifecycle_type }[1][:allow_null]).to be false
+
+    expect { Sequel::Migrator.run(db, migrations_path, target: current_migration_index, allow_missing_migration_files: true) }.not_to raise_error
+
+    Sequel::Migrator.run(db, migrations_path, target: current_migration_index - 1, allow_missing_migration_files: true)
+
+    expect(db.schema(:apps).find { |col| col[0] == :lifecycle_type }[1][:allow_null]).to be true
+    expect(db.schema(:droplets).find { |col| col[0] == :lifecycle_type }[1][:allow_null]).to be true
+    expect(db.schema(:builds).find { |col| col[0] == :lifecycle_type }[1][:allow_null]).to be true
+  end
+end