Merge branch 'smarter-cache-invalidation' into 'master'

Smarter cache invalidation

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/23550

See merge request !7360

app/models/project.rb

@@ -1086,7 +1086,7 @@ class Project < ActiveRecord::Base
                                         "refs/heads/#{branch}",
                                         force: true)
     repository.copy_gitattributes(branch)
-    repository.expire_avatar_cache(branch)
+    repository.expire_avatar_cache
     reload_default_branch
   end
 

app/models/tree.rb

@@ -18,7 +18,9 @@ class Tree
   def readme
     return @readme if defined?(@readme)
 
-    available_readmes = blobs.select(&:readme?)
+    available_readmes = blobs.select do |blob|
+      Gitlab::FileDetector.type_of(blob.name) == :readme
+    end
 
     previewable_readmes = available_readmes.select do |blob|
       previewable?(blob.name)

app/services/git_push_service.rb

@@ -18,7 +18,7 @@ class GitPushService < BaseService
   #
   def execute
     @project.repository.after_create if @project.empty_repo?
-    @project.repository.after_push_commit(branch_name, params[:newrev])
+    @project.repository.after_push_commit(branch_name)
 
     if push_remove_branch?
       @project.repository.after_remove_branch
@@ -51,12 +51,32 @@ class GitPushService < BaseService
 
     execute_related_hooks
     perform_housekeeping
+
+    update_caches
   end
 
   def update_gitattributes
     @project.repository.copy_gitattributes(params[:ref])
   end
 
+  def update_caches
+    if is_default_branch?
+      paths = Set.new
+
+      @push_commits.each do |commit|
+        commit.raw_diffs(deltas_only: true).each do |diff|
+          paths << diff.new_path
+        end
+      end
+
+      types = Gitlab::FileDetector.types_in_paths(paths.to_a)
+    else
+      types = []
+    end
+
+    ProjectCacheWorker.perform_async(@project.id, types)
+  end
+
   protected
 
   def execute_related_hooks
@@ -70,7 +90,6 @@ class GitPushService < BaseService
     @project.execute_hooks(build_push_data.dup, :push_hooks)
     @project.execute_services(build_push_data.dup, :push_hooks)
     Ci::CreatePipelineService.new(@project, current_user, build_push_data).execute
-    ProjectCacheWorker.perform_async(@project.id)
 
     if push_remove_branch?
       AfterBranchDeleteService

app/workers/project_cache_worker.rb

 # Worker for updating any project specific caches.
-#
-# This worker runs at most once every 15 minutes per project. This is to ensure
-# that multiple instances of jobs for this worker don't hammer the underlying
-# storage engine as much.
 class ProjectCacheWorker
   include Sidekiq::Worker
   include DedicatedSidekiqQueue
 
   LEASE_TIMEOUT = 15.minutes.to_i
 
-  def self.lease_for(project_id)
-    Gitlab::ExclusiveLease.
-      new("project_cache_worker:#{project_id}", timeout: LEASE_TIMEOUT)
-  end
-
-  # Overwrite Sidekiq's implementation so we only schedule when actually needed.
-  def self.perform_async(project_id)
-    # If a lease for this project is still being held there's no point in
-    # scheduling a new job.
-    super unless lease_for(project_id).exists?
-  end
+  # project_id - The ID of the project for which to flush the cache.
+  # refresh - An Array containing extra types of data to refresh such as
+  #           `:readme` to flush the README and `:changelog` to flush the
+  #           CHANGELOG.
+  def perform(project_id, refresh = [])
+    project = Project.find_by(id: project_id)
 
-  def perform(project_id)
-    if try_obtain_lease_for(project_id)
-      Rails.logger.
-        info("Obtained ProjectCacheWorker lease for project #{project_id}")
-    else
-      Rails.logger.
-        info("Could not obtain ProjectCacheWorker lease for project #{project_id}")
+    return unless project && project.repository.exists?
 
-      return
-    end
+    update_repository_size(project)
+    project.update_commit_count
 
-    update_caches(project_id)
+    project.repository.refresh_method_caches(refresh.map(&:to_sym))
   end
 
-  def update_caches(project_id)
-    project = Project.find(project_id)
+  def update_repository_size(project)
+    return unless try_obtain_lease_for(project.id, :update_repository_size)
 
-    return unless project.repository.exists?
+    Rails.logger.info("Updating repository size for project #{project.id}")
 
     project.update_repository_size
-    project.update_commit_count
-
-    if project.repository.root_ref
-      project.repository.build_cache
-    end
   end
 
-  def try_obtain_lease_for(project_id)
-    self.class.lease_for(project_id).try_obtain
+  private
+
+  def try_obtain_lease_for(project_id, section)
+    Gitlab::ExclusiveLease.
+      new("project_cache_worker:#{project_id}:#{section}", timeout: LEASE_TIMEOUT).
+      try_obtain
   end
 end

changelogs/unreleased/smarter-cache-invalidation.yml

+---
+title: Rework cache invalidation so only changed data is refreshed
+merge_request: 7360
+author: 

lib/gitlab/file_detector.rb

+require 'set'
+
+module Gitlab
+  # Module that can be used to detect if a path points to a special file such as
+  # a README or a CONTRIBUTING file.
+  module FileDetector
+    PATTERNS = {
+      readme: /\Areadme/i,
+      changelog: /\A(changelog|history|changes|news)/i,
+      license: /\A(licen[sc]e|copying)(\..+|\z)/i,
+      contributing: /\Acontributing/i,
+      version: 'version',
+      gitignore: '.gitignore',
+      koding: '.koding.yml',
+      gitlab_ci: '.gitlab-ci.yml',
+      avatar: /\Alogo\.(png|jpg|gif)\z/
+    }
+
+    # Returns an Array of file types based on the given paths.
+    #
+    # This method can be used to check if a list of file paths (e.g. of changed
+    # files) involve any special files such as a README or a LICENSE file.
+    #
+    # Example:
+    #
+    #     types_in_paths(%w{README.md foo/bar.txt}) # => [:readme]
+    def self.types_in_paths(paths)
+      types = Set.new
+
+      paths.each do |path|
+        type = type_of(path)
+
+        types << type if type
+      end
+
+      types.to_a
+    end
+
+    # Returns the type of a file path, or nil if none could be detected.
+    #
+    # Returned types are Symbols such as `:readme`, `:version`, etc.
+    #
+    # Example:
+    #
+    #     type_of('README.md') # => :readme
+    #     type_of('VERSION') # => :version
+    def self.type_of(path)
+      name = File.basename(path)
+
+      PATTERNS.each do |type, search|
+        did_match = if search.is_a?(Regexp)
+                      name =~ search
+                    else
+                      name.casecmp(search) == 0
+                    end
+
+        return type if did_match
+      end
+
+      nil
+    end
+  end
+end

spec/lib/gitlab/file_detector_spec.rb

+require 'spec_helper'
+
+describe Gitlab::FileDetector do
+  describe '.types_in_paths' do
+    it 'returns the file types for the given paths' do
+      expect(described_class.types_in_paths(%w(README.md CHANGELOG VERSION VERSION))).
+        to eq(%i{readme changelog version})
+    end
+
+    it 'does not include unrecognized file paths' do
+      expect(described_class.types_in_paths(%w(README.md foo.txt))).
+        to eq(%i{readme})
+    end
+  end
+
+  describe '.type_of' do
+    it 'returns the type of a README file' do
+      expect(described_class.type_of('README.md')).to eq(:readme)
+    end
+
+    it 'returns the type of a changelog file' do
+      %w(CHANGELOG HISTORY CHANGES NEWS).each do |file|
+        expect(described_class.type_of(file)).to eq(:changelog)
+      end
+    end
+
+    it 'returns the type of a license file' do
+      %w(LICENSE LICENCE COPYING).each do |file|
+        expect(described_class.type_of(file)).to eq(:license)
+      end
+    end
+
+    it 'returns the type of a version file' do
+      expect(described_class.type_of('VERSION')).to eq(:version)
+    end
+
+    it 'returns the type of a .gitignore file' do
+      expect(described_class.type_of('.gitignore')).to eq(:gitignore)
+    end
+
+    it 'returns the type of a Koding config file' do
+      expect(described_class.type_of('.koding.yml')).to eq(:koding)
+    end
+
+    it 'returns the type of a GitLab CI config file' do
+      expect(described_class.type_of('.gitlab-ci.yml')).to eq(:gitlab_ci)
+    end
+
+    it 'returns the type of an avatar' do
+      %w(logo.gif logo.png logo.jpg).each do |file|
+        expect(described_class.type_of(file)).to eq(:avatar)
+      end
+    end
+
+    it 'returns nil for an unknown file' do
+      expect(described_class.type_of('foo.txt')).to be_nil
+    end
+  end
+end

spec/models/project_spec.rb

@@ -1572,7 +1572,7 @@ describe Project, models: true do
     end
 
     it 'expires the avatar cache' do
-      expect(project.repository).to receive(:expire_avatar_cache).with(project.default_branch)
+      expect(project.repository).to receive(:expire_avatar_cache)
       project.change_head(project.default_branch)
     end
 

spec/requests/api/branches_spec.rb

@@ -14,7 +14,7 @@ describe API::API, api: true  do
 
   describe "GET /projects/:id/repository/branches" do
     it "returns an array of project branches" do
-      project.repository.expire_cache
+      project.repository.expire_all_method_caches
 
       get api("/projects/#{project.id}/repository/branches", user)
       expect(response).to have_http_status(200)

spec/services/git_push_service_spec.rb

@@ -27,27 +27,14 @@ describe GitPushService, services: true do
 
       it { is_expected.to be_truthy }
 
-      it 'flushes general cached data' do
-        expect(project.repository).to receive(:expire_cache).
-          with('master', newrev)
+      it 'calls the after_push_commit hook' do
+        expect(project.repository).to receive(:after_push_commit).with('master')
 
         subject
       end
 
-      it 'flushes the visible content cache' do
-        expect(project.repository).to receive(:expire_has_visible_content_cache)
-
-        subject
-      end
-
-      it 'flushes the branches cache' do
-        expect(project.repository).to receive(:expire_branches_cache)
-
-        subject
-      end
-
-      it 'flushes the branch count cache' do
-        expect(project.repository).to receive(:expire_branch_count_cache)
+      it 'calls the after_create_branch hook' do
+        expect(project.repository).to receive(:after_create_branch)
 
         subject
       end
@@ -56,21 +43,8 @@ describe GitPushService, services: true do
     context 'existing branch' do
       it { is_expected.to be_truthy }
 
-      it 'flushes general cached data' do
-        expect(project.repository).to receive(:expire_cache).
-          with('master', newrev)
-
-        subject
-      end
-
-      it 'does not flush the branches cache' do
-        expect(project.repository).not_to receive(:expire_branches_cache)
-
-        subject
-      end
-
-      it 'does not flush the branch count cache' do
-        expect(project.repository).not_to receive(:expire_branch_count_cache)
+      it 'calls the after_push_commit hook' do
+        expect(project.repository).to receive(:after_push_commit).with('master')
 
         subject
       end
@@ -81,27 +55,14 @@ describe GitPushService, services: true do
 
       it { is_expected.to be_truthy }
 
-      it 'flushes the visible content cache' do
-        expect(project.repository).to receive(:expire_has_visible_content_cache)
-
-        subject
-      end
-
-      it 'flushes the branches cache' do
-        expect(project.repository).to receive(:expire_branches_cache)
-
-        subject
-      end
-
-      it 'flushes the branch count cache' do
-        expect(project.repository).to receive(:expire_branch_count_cache)
+      it 'calls the after_push_commit hook' do
+        expect(project.repository).to receive(:after_push_commit).with('master')
 
         subject
       end
 
-      it 'flushes general cached data' do
-        expect(project.repository).to receive(:expire_cache).
-          with('master', newrev)
+      it 'calls the after_remove_branch hook' do
+        expect(project.repository).to receive(:after_remove_branch)
 
         subject
       end
@@ -598,6 +559,51 @@ describe GitPushService, services: true do
     end
   end
 
+  describe '#update_caches' do
+    let(:service) do
+      described_class.new(project,
+                          user,
+                          oldrev: sample_commit.parent_id,
+                          newrev: sample_commit.id,
+                          ref: 'refs/heads/master')
+    end
+
+    context 'on the default branch' do
+      before do
+        allow(service).to receive(:is_default_branch?).and_return(true)
+      end
+
+      it 'flushes the caches of any special files that have been changed' do
+        commit = double(:commit)
+        diff = double(:diff, new_path: 'README.md')
+
+        expect(commit).to receive(:raw_diffs).with(deltas_only: true).
+          and_return([diff])
+
+        service.push_commits = [commit]
+
+        expect(ProjectCacheWorker).to receive(:perform_async).
+          with(project.id, %i(readme))
+
+        service.update_caches
+      end
+    end
+
+    context 'on a non-default branch' do
+      before do
+        allow(service).to receive(:is_default_branch?).and_return(false)
+      end
+
+      it 'does not flush any conditional caches' do
+        expect(ProjectCacheWorker).to receive(:perform_async).
+          with(project.id, []).
+          and_call_original
+
+        service.update_caches
+      end
+    end
+  end
+
   def execute_service(project, user, oldrev, newrev, ref)
     service = described_class.new(project, user, oldrev: oldrev, newrev: newrev, ref: ref )
     service.execute

spec/services/git_tag_push_service_spec.rb

@@ -18,7 +18,7 @@ describe GitTagPushService, services: true do
     end
 
     it 'flushes general cached data' do
-      expect(project.repository).to receive(:expire_cache)
+      expect(project.repository).to receive(:before_push_tag)
 
       subject
     end
@@ -28,12 +28,6 @@ describe GitTagPushService, services: true do
 
       subject
     end
-
-    it 'flushes the tag count cache' do
-      expect(project.repository).to receive(:expire_tag_count_cache)
-
-      subject
-    end
   end
 
   describe "Git Tag Push Data" do

spec/workers/project_cache_worker_spec.rb

@@ -2,62 +2,78 @@ require 'spec_helper'
 
 describe ProjectCacheWorker do
   let(:project) { create(:project) }
+  let(:worker) { described_class.new }
 
-  subject { described_class.new }
-
-  describe '.perform_async' do
-    it 'schedules the job when no lease exists' do
-      allow_any_instance_of(Gitlab::ExclusiveLease).to receive(:exists?).
-        and_return(false)
+  describe '#perform' do
+    before do
+      allow_any_instance_of(Gitlab::ExclusiveLease).to receive(:try_obtain).
+        and_return(true)
+    end
 
-      expect_any_instance_of(described_class).to receive(:perform)
+    context 'with a non-existing project' do
+      it 'does nothing' do
+        expect(worker).not_to receive(:update_repository_size)
 
-      described_class.perform_async(project.id)
+        worker.perform(-1)
+      end
     end
 
-    it 'does not schedule the job when a lease exists' do
-      allow_any_instance_of(Gitlab::ExclusiveLease).to receive(:exists?).
-        and_return(true)
+    context 'with an existing project without a repository' do
+      it 'does nothing' do
+        allow_any_instance_of(Repository).to receive(:exists?).and_return(false)
 
-      expect_any_instance_of(described_class).not_to receive(:perform)
+        expect(worker).not_to receive(:update_repository_size)
 
-      described_class.perform_async(project.id)
+        worker.perform(project.id)
       end
     end
 
-  describe '#perform' do
-    context 'when an exclusive lease can be obtained' do
-      before do
-        allow(subject).to receive(:try_obtain_lease_for).with(project.id).
-          and_return(true)
-      end
+    context 'with an existing project' do
+      it 'updates the repository size' do
+        expect(worker).to receive(:update_repository_size).and_call_original
 
-      it 'updates project cache data' do
-        expect_any_instance_of(Repository).to receive(:size)
-        expect_any_instance_of(Repository).to receive(:commit_count)
+        worker.perform(project.id)
+      end
 
-        expect_any_instance_of(Project).to receive(:update_repository_size)
-        expect_any_instance_of(Project).to receive(:update_commit_count)
+      it 'updates the commit count' do
+        expect_any_instance_of(Project).to receive(:update_commit_count).
+          and_call_original
 
-        subject.perform(project.id)
+        worker.perform(project.id)
       end
 
-      it 'handles missing repository data' do
-        expect_any_instance_of(Repository).to receive(:exists?).and_return(false)
-        expect_any_instance_of(Repository).not_to receive(:size)
+      it 'refreshes the method caches' do
+        expect_any_instance_of(Repository).to receive(:refresh_method_caches).
+          with(%i(readme)).
+          and_call_original
 
-        subject.perform(project.id)
+        worker.perform(project.id, %i(readme))
+      end
     end
   end
 
-    context 'when an exclusive lease can not be obtained' do
-      it 'does nothing' do
-        allow(subject).to receive(:try_obtain_lease_for).with(project.id).
+  describe '#update_repository_size' do
+    context 'when a lease could not be obtained' do
+      it 'does not update the repository size' do
+        allow(worker).to receive(:try_obtain_lease_for).
+          with(project.id, :update_repository_size).
           and_return(false)
 
-        expect(subject).not_to receive(:update_caches)
+        expect(project).not_to receive(:update_repository_size)
+
+        worker.update_repository_size(project)
+      end
+    end
+
+    context 'when a lease could be obtained' do
+      it 'updates the repository size' do
+        allow(worker).to receive(:try_obtain_lease_for).
+          with(project.id, :update_repository_size).
+          and_return(true)
+
+        expect(project).to receive(:update_repository_size).and_call_original
 
-        subject.perform(project.id)
+        worker.update_repository_size(project)
       end
     end
   end