Foreground verification of uploads and LFS objects

app/models/lfs_object.rb

@@ -18,4 +18,8 @@ class LfsObject < ActiveRecord::Base
         .where(lfs_objects_projects: { id: nil })
         .destroy_all
   end
+
+  def self.calculate_oid(path)
+    Digest::SHA256.file(path).hexdigest
+  end
 end

changelogs/unreleased/ee-4862-verify-file-checksums.yml

+---
+title: Foreground verification of uploads and LFS objects
+merge_request: 17402
+author:
+type: added

doc/administration/raketasks/check.md

@@ -78,34 +78,41 @@ Example output:
 
 ## Uploaded Files Integrity
 
-The uploads check Rake task will loop through all uploads in the database
-and run two checks to determine the integrity of each file:
+Various types of file can be uploaded to a GitLab installation by users.
+Checksums are generated and stored in the database upon upload, and integrity
+checks using those checksums can be run. These checks also detect missing files.
 
-1. Check if the file exist on the file system.
-1. Check if the checksum of the file on the file system matches the checksum in the database.
+Currently, integrity checks are supported for the following types of file:
+
+* LFS objects
+* User uploads
 
 **Omnibus Installation**
 
 ```
+sudo gitlab-rake gitlab:lfs:check
 sudo gitlab-rake gitlab:uploads:check
 ```
 
 **Source Installation**
 
 ```bash
+sudo -u git -H bundle exec rake gitlab:lfs:check RAILS_ENV=production
 sudo -u git -H bundle exec rake gitlab:uploads:check RAILS_ENV=production
 ```
 
-This task also accepts some environment variables which you can use to override
+These tasks also accept some environment variables which you can use to override
 certain values:
 
 Variable  | Type    | Description
--------- | ---- | -----------
+--------- | ------- | -----------
 `BATCH`   | integer | Specifies the size of the batch. Defaults to 200.
 `ID_FROM` | integer | Specifies the ID to start from, inclusive of the value.
 `ID_TO`   | integer | Specifies the ID value to end at, inclusive of the value.
+`VERBOSE` | boolean | Causes failures to be listed individually, rather than being summarized.
 
 ```bash
+sudo gitlab-rake gitlab:lfs:check BATCH=100 ID_FROM=50 ID_TO=250
 sudo gitlab-rake gitlab:uploads:check BATCH=100 ID_FROM=50 ID_TO=250
 ```
 

lib/gitlab/verify/batch_verifier.rb

+module Gitlab
+  module Verify
+    class BatchVerifier
+      attr_reader :batch_size, :start, :finish
+
+      def initialize(batch_size:, start: nil, finish: nil)
+        @batch_size = batch_size
+        @start = start
+        @finish = finish
+      end
+
+      # Yields a Range of IDs and a Hash of failed verifications (object => error)
+      def run_batches(&blk)
+        relation.in_batches(of: batch_size, start: start, finish: finish) do |relation| # rubocop: disable Cop/InBatches
+          range = relation.first.id..relation.last.id
+          failures = run_batch(relation)
+
+          yield(range, failures)
+        end
+      end
+
+      def name
+        raise NotImplementedError.new
+      end
+
+      def describe(_object)
+        raise NotImplementedError.new
+      end
+
+      private
+
+      def run_batch(relation)
+        relation.map { |upload| verify(upload) }.compact.to_h
+      end
+
+      def verify(object)
+        expected = expected_checksum(object)
+        actual = actual_checksum(object)
+
+        raise 'Checksum missing' unless expected.present?
+        raise 'Checksum mismatch' unless expected == actual
+
+        nil
+      rescue => err
+        [object, err]
+      end
+
+      # This should return an ActiveRecord::Relation suitable for calling #in_batches on
+      def relation
+        raise NotImplementedError.new
+      end
+
+      # The checksum we expect the object to have
+      def expected_checksum(_object)
+        raise NotImplementedError.new
+      end
+
+      # The freshly-recalculated checksum of the object
+      def actual_checksum(_object)
+        raise NotImplementedError.new
+      end
+    end
+  end
+end

lib/gitlab/verify/lfs_objects.rb

+module Gitlab
+  module Verify
+    class LfsObjects < BatchVerifier
+      def name
+        'LFS objects'
+      end
+
+      def describe(object)
+        "LFS object: #{object.oid}"
+      end
+
+      private
+
+      def relation
+        LfsObject.all
+      end
+
+      def expected_checksum(lfs_object)
+        lfs_object.oid
+      end
+
+      def actual_checksum(lfs_object)
+        LfsObject.calculate_oid(lfs_object.file.path)
+      end
+    end
+  end
+end

lib/gitlab/verify/rake_task.rb

+module Gitlab
+  module Verify
+    class RakeTask
+      def self.run!(verify_kls)
+        verifier = verify_kls.new(
+          batch_size: ENV.fetch('BATCH', 200).to_i,
+          start: ENV['ID_FROM'],
+          finish: ENV['ID_TO']
+        )
+
+        verbose = Gitlab::Utils.to_boolean(ENV['VERBOSE'])
+
+        new(verifier, verbose).run!
+      end
+
+      attr_reader :verifier, :output
+
+      def initialize(verifier, verbose)
+        @verifier = verifier
+        @verbose = verbose
+      end
+
+      def run!
+        say "Checking integrity of #{verifier.name}"
+
+        verifier.run_batches { |*args| run_batch(*args) }
+
+        say 'Done!'
+      end
+
+      def verbose?
+        !!@verbose
+      end
+
+      private
+
+      def say(text)
+        puts(text) # rubocop:disable Rails/Output
+      end
+
+      def run_batch(range, failures)
+        status_color = failures.empty? ? :green : :red
+        say "- #{range}: Failures: #{failures.count}".color(status_color)
+
+        return unless verbose?
+
+        failures.each do |object, error|
+          say "  - #{verifier.describe(object)}: #{error.inspect}".color(:red)
+        end
+      end
+    end
+  end
+end

lib/gitlab/verify/uploads.rb

+module Gitlab
+  module Verify
+    class Uploads < BatchVerifier
+      def name
+        'Uploads'
+      end
+
+      def describe(object)
+        "Upload: #{object.id}"
+      end
+
+      private
+
+      def relation
+        Upload.all
+      end
+
+      def expected_checksum(upload)
+        upload.checksum
+      end
+
+      def actual_checksum(upload)
+        Upload.hexdigest(upload.absolute_path)
+      end
+    end
+  end
+end

lib/tasks/gitlab/lfs/check.rake

+namespace :gitlab do
+  namespace :lfs do
+    desc 'GitLab | LFS | Check integrity of uploaded LFS objects'
+    task check: :environment do
+      Gitlab::Verify::RakeTask.run!(Gitlab::Verify::LfsObjects)
+    end
+  end
+end

lib/tasks/gitlab/uploads/check.rake

+namespace :gitlab do
+  namespace :uploads do
+    desc 'GitLab | Uploads | Check integrity of uploaded files'
+    task check: :environment do
+      Gitlab::Verify::RakeTask.run!(Gitlab::Verify::Uploads)
+    end
+  end
+end

spec/factories/lfs_objects.rb

@@ -9,4 +9,10 @@ FactoryBot.define do
   trait :with_file do
     file { fixture_file_upload(Rails.root + "spec/fixtures/dk.png", "`/png") }
   end
+
+  # The uniqueness constraint means we can't use the correct OID for all LFS
+  # objects, so the test needs to decide which (if any) object gets it
+  trait :correct_oid do
+    oid 'b804383982bb89b00e828e3f44c038cc991d3d1768009fc39ba8e2c081b9fb75'
+  end
 end

spec/lib/gitlab/verify/lfs_objects_spec.rb

+require 'spec_helper'
+
+describe Gitlab::Verify::LfsObjects do
+  include GitlabVerifyHelpers
+
+  it_behaves_like 'Gitlab::Verify::BatchVerifier subclass' do
+    let!(:objects) { create_list(:lfs_object, 3, :with_file) }
+  end
+
+  describe '#run_batches' do
+    let(:failures) { collect_failures }
+    let(:failure) { failures[lfs_object] }
+
+    let!(:lfs_object) { create(:lfs_object, :with_file, :correct_oid) }
+
+    it 'passes LFS objects with the correct file' do
+      expect(failures).to eq({})
+    end
+
+    it 'fails LFS objects with a missing file' do
+      FileUtils.rm_f(lfs_object.file.path)
+
+      expect(failures.keys).to contain_exactly(lfs_object)
+      expect(failure).to be_a(Errno::ENOENT)
+      expect(failure.to_s).to include(lfs_object.file.path)
+    end
+
+    it 'fails LFS objects with a mismatched oid' do
+      File.truncate(lfs_object.file.path, 0)
+
+      expect(failures.keys).to contain_exactly(lfs_object)
+      expect(failure.to_s).to include('Checksum mismatch')
+    end
+  end
+end

spec/lib/gitlab/verify/uploads_spec.rb

+require 'spec_helper'
+
+describe Gitlab::Verify::Uploads do
+  include GitlabVerifyHelpers
+
+  it_behaves_like 'Gitlab::Verify::BatchVerifier subclass' do
+    let(:projects) { create_list(:project, 3, :with_avatar) }
+    let!(:objects) { projects.flat_map(&:uploads) }
+  end
+
+  describe '#run_batches' do
+    let(:project) { create(:project, :with_avatar) }
+    let(:failures) { collect_failures }
+    let(:failure) { failures[upload] }
+
+    let!(:upload) { project.uploads.first }
+
+    it 'passes uploads with the correct file' do
+      expect(failures).to eq({})
+    end
+
+    it 'fails uploads with a missing file' do
+      FileUtils.rm_f(upload.absolute_path)
+
+      expect(failures.keys).to contain_exactly(upload)
+      expect(failure).to be_a(Errno::ENOENT)
+      expect(failure.to_s).to include(upload.absolute_path)
+    end
+
+    it 'fails uploads with a mismatched checksum' do
+      upload.update!(checksum: 'something incorrect')
+
+      expect(failures.keys).to contain_exactly(upload)
+      expect(failure.to_s).to include('Checksum mismatch')
+    end
+
+    it 'fails uploads with a missing precalculated checksum' do
+      upload.update!(checksum: '')
+
+      expect(failures.keys).to contain_exactly(upload)
+      expect(failure.to_s).to include('Checksum missing')
+    end
+  end
+end

spec/support/gitlab_verify.rb

+RSpec.shared_examples 'Gitlab::Verify::BatchVerifier subclass' do
+  describe 'batching' do
+    let(:first_batch) { objects[0].id..objects[0].id }
+    let(:second_batch) { objects[1].id..objects[1].id }
+    let(:third_batch) { objects[2].id..objects[2].id }
+
+    it 'iterates through objects in batches' do
+      expect(collect_ranges).to eq([first_batch, second_batch, third_batch])
+    end
+
+    it 'allows the starting ID to be specified' do
+      expect(collect_ranges(start: second_batch.first)).to eq([second_batch, third_batch])
+    end
+
+    it 'allows the finishing ID to be specified' do
+      expect(collect_ranges(finish: second_batch.last)).to eq([first_batch, second_batch])
+    end
+  end
+end
+
+module GitlabVerifyHelpers
+  def collect_ranges(args = {})
+    verifier = described_class.new(args.merge(batch_size: 1))
+
+    collect_results(verifier).map { |range, _| range }
+  end
+
+  def collect_failures
+    verifier = described_class.new(batch_size: 1)
+
+    out = {}
+
+    collect_results(verifier).map { |_, failures| out.merge!(failures) }
+
+    out
+  end
+
+  def collect_results(verifier)
+    out = []
+
+    verifier.run_batches { |*args| out << args }
+
+    out
+  end
+end

spec/tasks/gitlab/lfs/check_rake_spec.rb

+require 'rake_helper'
+
+describe 'gitlab:lfs rake tasks' do
+  describe 'check' do
+    let!(:lfs_object) { create(:lfs_object, :with_file, :correct_oid) }
+
+    before do
+      Rake.application.rake_require('tasks/gitlab/lfs/check')
+      stub_env('VERBOSE' => 'true')
+    end
+
+    it 'outputs the integrity check for each batch' do
+      expect { run_rake_task('gitlab:lfs:check') }.to output(/Failures: 0/).to_stdout
+    end
+
+    it 'errors out about missing files on the file system' do
+      FileUtils.rm_f(lfs_object.file.path)
+
+      expect { run_rake_task('gitlab:lfs:check') }.to output(/No such file.*#{Regexp.quote(lfs_object.file.path)}/).to_stdout
+    end
+
+    it 'errors out about invalid checksum' do
+      File.truncate(lfs_object.file.path, 0)
+
+      expect { run_rake_task('gitlab:lfs:check') }.to output(/Checksum mismatch/).to_stdout
+    end
+  end
+end

spec/tasks/gitlab/uploads/check_rake_spec.rb

+require 'rake_helper'
+
+describe 'gitlab:uploads rake tasks' do
+  describe 'check' do
+    let!(:upload) { create(:upload, path: Rails.root.join('spec/fixtures/banana_sample.gif')) }
+
+    before do
+      Rake.application.rake_require('tasks/gitlab/uploads/check')
+      stub_env('VERBOSE' => 'true')
+    end
+
+    it 'outputs the integrity check for each batch' do
+      expect { run_rake_task('gitlab:uploads:check') }.to output(/Failures: 0/).to_stdout
+    end
+
+    it 'errors out about missing files on the file system' do
+      missing_upload = create(:upload)
+
+      expect { run_rake_task('gitlab:uploads:check') }.to output(/No such file.*#{Regexp.quote(missing_upload.absolute_path)}/).to_stdout
+    end
+
+    it 'errors out about invalid checksum' do
+      upload.update_column(:checksum, '01a3156db2cf4f67ec823680b40b7302f89ab39179124ad219f94919b8a1769e')
+
+      expect { run_rake_task('gitlab:uploads:check') }.to output(/Checksum mismatch/).to_stdout
+    end
+  end
+end