1 files changed, 80 insertions, 0 deletions
diff --git a/app/services/lfs/push_service.rb b/app/services/lfs/push_service.rb
new file mode 100644
index 00000000000..6e1a11ebff8
--- /dev/null
+++ b/app/services/lfs/push_service.rb
@@ -0,0 +1,80 @@
+# frozen_string_literal: true
+
+module Lfs
+  # Lfs::PushService pushes the LFS objects associated with a project to a
+  # remote URL
+  class PushService < BaseService
+    include Gitlab::Utils::StrongMemoize
+
+    # Match the canonical LFS client's batch size:
+    # https://github.com/git-lfs/git-lfs/blob/master/tq/transfer_queue.go#L19
+    BATCH_SIZE = 100
+
+    def execute
+      lfs_objects_relation.each_batch(of: BATCH_SIZE) do |objects|
+        push_objects(objects)
+      end
+
+      success
+    rescue => err
+      error(err.message)
+    end
+
+    private
+
+    # Currently we only set repository_type for design repository objects, so
+    # push mirroring must send objects with a `nil` repository type - but if the
+    # wiki repository uses LFS, its objects will also be sent. This will be
+    # addressed by https://gitlab.com/gitlab-org/gitlab/-/issues/250346
+    def lfs_objects_relation
+      project.lfs_objects_for_repository_types(nil, :project)
+    end
+
+    def push_objects(objects)
+      rsp = lfs_client.batch('upload', objects)
+      objects = objects.index_by(&:oid)
+
+      rsp.fetch('objects', []).each do |spec|
+        actions = spec['actions']
+        object = objects[spec['oid']]
+
+        upload_object!(object, spec) if actions&.key?('upload')
+        verify_object!(object, spec) if actions&.key?('verify')
+      end
+    end
+
+    def upload_object!(object, spec)
+      authenticated = spec['authenticated']
+      upload = spec.dig('actions', 'upload')
+
+      # The server wants us to upload the object but something is wrong
+      unless object && object.size == spec['size'].to_i
+        log_error("Couldn't match object #{spec['oid']}/#{spec['size']}")
+        return
+      end
+
+      lfs_client.upload(object, upload, authenticated: authenticated)
+    end
+
+    def verify_object!(object, spec)
+      # TODO: the remote has requested that we make another call to verify that
+      # the object has been sent correctly.
+      # https://gitlab.com/gitlab-org/gitlab/-/issues/250654
+      log_error("LFS upload verification requested, but not supported for #{object.oid}")
+    end
+
+    def url
+      params.fetch(:url)
+    end
+
+    def credentials
+      params.fetch(:credentials)
+    end
+
+    def lfs_client
+      strong_memoize(:lfs_client) do
+        Gitlab::Lfs::Client.new(url, credentials: credentials)
+      end
+    end
+  end
+end