Trim trailing newline from orphan files to delete

The trailing newline was actually causing the
FileUtils.rm_rf() call to _look_ like it was
working, but was in fact not deleting at all.

changelogs/unreleased/32534-gitlab-rake-gitlab-cleanup-orphan_job_artifact_files-dry_run-false-is-not-removing-artifacts.yml

+---
+title: Correctly cleanup orphan job artifacts
+merge_request: 17679
+author: Adam Mulvany
+type: fixed

lib/gitlab/cleanup/orphan_job_artifact_files.rb

@@ -8,7 +8,8 @@ module Gitlab
       ABSOLUTE_ARTIFACT_DIR = ::JobArtifactUploader.root.freeze
       LOST_AND_FOUND = File.join(ABSOLUTE_ARTIFACT_DIR, '-', 'lost+found').freeze
       BATCH_SIZE = 500
-      DEFAULT_NICENESS = 'Best-effort'
+      DEFAULT_NICENESS = 'best-effort'
+      VALID_NICENESS_LEVELS = %w{none realtime best-effort idle}.freeze
 
       attr_accessor :batch, :total_found, :total_cleaned
       attr_reader :limit, :dry_run, :niceness, :logger
@@ -16,7 +17,7 @@ module Gitlab
       def initialize(limit: nil, dry_run: true, niceness: nil, logger: nil)
         @limit = limit
         @dry_run = dry_run
-        @niceness = niceness || DEFAULT_NICENESS
+        @niceness = (niceness || DEFAULT_NICENESS).downcase
         @logger = logger || Rails.logger # rubocop:disable Gitlab/RailsLogger
         @total_found = @total_cleaned = 0
 
@@ -35,7 +36,7 @@ module Gitlab
 
         clean_batch!
 
-        log_info("Processed #{total_found} job artifacts to find and clean #{total_cleaned} orphans.")
+        log_info("Processed #{total_found} job artifact(s) to find and cleaned #{total_cleaned} orphan(s).")
       end
 
       private
@@ -75,7 +76,7 @@ module Gitlab
       def find_artifacts
         Open3.popen3(*find_command) do |stdin, stdout, stderr, status_thread|
           stdout.each_line do |line|
-            yield line
+            yield line.chomp
           end
 
           log_error(stderr.read.color(:red)) unless status_thread.value.success?
@@ -99,7 +100,7 @@ module Gitlab
           cmd += %w[-type d]
 
           if ionice
-            raise ArgumentError, 'Invalid niceness' unless niceness.match?(/^\w[\w\-]*$/)
+            raise ArgumentError, 'Invalid niceness' unless VALID_NICENESS_LEVELS.include?(niceness)
 
             cmd.unshift(*%W[#{ionice} --class #{niceness}])
           end

spec/lib/gitlab/cleanup/orphan_job_artifact_files_spec.rb

@@ -21,11 +21,10 @@ describe Gitlab::Cleanup::OrphanJobArtifactFiles do
   end
 
   it 'errors when invalid niceness is given' do
+    allow(Gitlab::Utils).to receive(:which).with('ionice').and_return('/fake/ionice')
     cleanup = described_class.new(logger: null_logger, niceness: 'FooBar')
 
-    expect(null_logger).to receive(:error).with(/FooBar/)
-
-    cleanup.run!
+    expect { cleanup.run! }.to raise_error('Invalid niceness')
   end
 
   it 'finds artifacts on disk' do
@@ -63,6 +62,8 @@ describe Gitlab::Cleanup::OrphanJobArtifactFiles do
   def mock_artifacts_found(cleanup, *files)
     mock = allow(cleanup).to receive(:find_artifacts)
 
-    files.each { |file| mock.and_yield(file) }
+    # Because we shell out to run `find -L ...`, each file actually
+    # contains a trailing newline
+    files.each { |file| mock.and_yield("#{file}\n") }
   end
 end