Add pipeline artifact uploader

This new uploader will be used to upload reports
persisted in a pipeline context consumable by gitlab
frontend.

app/models/ci/pipeline_artifact.rb

@@ -22,8 +22,22 @@ module Ci
     validates :size, presence: true, numericality: { less_than_or_equal_to: FILE_SIZE_LIMIT }
     validates :file_type, presence: true
 
+    mount_uploader :file, Ci::PipelineArtifactUploader
+    before_save :set_size, if: :file_changed?
+    after_save :update_file_store, if: :saved_change_to_file?
+
     enum file_type: {
       code_coverage: 1
     }
+
+    def set_size
+      self.size = file.size
+    end
+
+    def update_file_store
+      # The file.object_store is set during `uploader.store!`
+      # which happens after object is inserted/updated
+      self.update_column(:file_store, file.object_store)
+    end
   end
 end

app/uploaders/ci/pipeline_artifact_uploader.rb

+# frozen_string_literal: true
+
+module Ci
+  class PipelineArtifactUploader < GitlabUploader
+    include ObjectStorage::Concern
+
+    storage_options Gitlab.config.artifacts
+
+    alias_method :upload, :model
+
+    def store_dir
+      dynamic_segment
+    end
+
+    private
+
+    def dynamic_segment
+      Gitlab::HashedPath.new('pipelines', model.pipeline_id, 'artifacts', model.id, root_hash: model.project_id)
+    end
+  end
+end

spec/models/ci/pipeline_artifact_spec.rb

@@ -43,4 +43,34 @@ RSpec.describe Ci::PipelineArtifact, type: :model do
       end
     end
   end
+
+  describe '#set_size' do
+    subject { create(:ci_pipeline_artifact) }
+
+    context 'when file is being created' do
+      it 'sets the size' do
+        expect(subject.size).to eq(85)
+      end
+    end
+
+    context 'when file is being updated' do
+      it 'updates the size' do
+        subject.update!(file: fixture_file_upload('spec/fixtures/dk.png'))
+
+        expect(subject.size).to eq(1062)
+      end
+    end
+  end
+
+  describe 'file is being stored' do
+    subject { create(:ci_pipeline_artifact) }
+
+    context 'when existing object has local store' do
+      it 'is stored locally' do
+        expect(subject.file_store).to be(ObjectStorage::Store::LOCAL)
+        expect(subject.file).to be_file_storage
+        expect(subject.file.object_store).to eq(ObjectStorage::Store::LOCAL)
+      end
+    end
+  end
 end

spec/support/helpers/stub_object_storage.rb

@@ -47,9 +47,9 @@ module StubObjectStorage
     end
   end
 
-  def stub_artifacts_object_storage(**params)
+  def stub_artifacts_object_storage(uploader = JobArtifactUploader, **params)
     stub_object_storage_uploader(config: Gitlab.config.artifacts.object_store,
-                                 uploader: JobArtifactUploader,
+                                 uploader: uploader,
                                  remote_directory: 'artifacts',
                                  **params)
   end

spec/uploaders/ci/pipeline_artifact_uploader_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Ci::PipelineArtifactUploader do
+  let(:pipeline_artifact) { create(:ci_pipeline_artifact) }
+  let(:uploader) { described_class.new(pipeline_artifact, :file) }
+
+  subject { uploader }
+
+  it_behaves_like "builds correct paths",
+                  store_dir: %r[\h{2}/\h{2}/\h{64}/pipelines/\d+/artifacts/\d+],
+                  cache_dir: %r[artifacts/tmp/cache],
+                  work_dir: %r[artifacts/tmp/work]
+
+  context 'when object store is REMOTE' do
+    before do
+      stub_artifacts_object_storage(described_class)
+    end
+
+    include_context 'with storage', described_class::Store::REMOTE
+
+    it_behaves_like 'builds correct paths', store_dir: %r[\h{2}/\h{2}/\h{64}/pipelines/\d+/artifacts/\d+]
+  end
+
+  context 'when file is stored in valid local_path' do
+    let(:file) do
+      fixture_file_upload('spec/fixtures/pipeline_artifacts/code_coverage.json', 'application/json')
+    end
+
+    before do
+      uploader.store!(file)
+    end
+
+    subject { uploader.file.path }
+
+    it { is_expected.to match(%r[#{uploader.root}/#{uploader.class.base_dir}\h{2}/\h{2}/\h{64}/pipelines/#{pipeline_artifact.pipeline_id}/artifacts/#{pipeline_artifact.id}/code_coverage.json]) }
+  end
+end