1 files changed, 84 insertions, 0 deletions
diff --git a/lib/gitlab/github_gists_import/importer/gist_importer.rb b/lib/gitlab/github_gists_import/importer/gist_importer.rb
new file mode 100644
index 00000000000..a5e87d3cf7d
--- /dev/null
+++ b/lib/gitlab/github_gists_import/importer/gist_importer.rb
@@ -0,0 +1,84 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module GithubGistsImport
+    module Importer
+      class GistImporter
+        attr_reader :gist, :user
+
+        FileCountLimitError = Class.new(StandardError)
+
+        # gist - An instance of `Gitlab::GithubGistsImport::Representation::Gist`.
+        def initialize(gist, user_id)
+          @gist = gist
+          @user = User.find(user_id)
+        end
+
+        def execute
+          snippet = build_snippet
+          import_repository(snippet) if snippet.save!
+
+          return ServiceResponse.success unless max_snippet_files_count_exceeded?(snippet)
+
+          fail_and_track(snippet)
+        end
+
+        private
+
+        def build_snippet
+          attrs = {
+            title: gist.truncated_title,
+            visibility_level: gist.visibility_level,
+            content: gist.first_file[:file_content],
+            file_name: gist.first_file[:file_name],
+            author: user,
+            created_at: gist.created_at,
+            updated_at: gist.updated_at
+          }
+
+          PersonalSnippet.new(attrs)
+        end
+
+        def import_repository(snippet)
+          resolved_address = get_resolved_address
+
+          snippet.create_repository
+          snippet.repository.fetch_as_mirror(gist.git_pull_url, forced: true, resolved_address: resolved_address)
+        rescue StandardError
+          remove_snippet_and_repository(snippet)
+
+          raise
+        end
+
+        def get_resolved_address
+          validated_pull_url, host = Gitlab::UrlBlocker.validate!(gist.git_pull_url,
+                                      schemes: Project::VALID_IMPORT_PROTOCOLS,
+                                      ports: Project::VALID_IMPORT_PORTS,
+                                      allow_localhost: allow_local_requests?,
+                                      allow_local_network: allow_local_requests?)
+
+          host.present? ? validated_pull_url.host.to_s : ''
+        end
+
+        def max_snippet_files_count_exceeded?(snippet)
+          snippet.all_files.size > Snippet.max_file_limit
+        end
+
+        def remove_snippet_and_repository(snippet)
+          snippet.repository.remove if snippet.repository_exists?
+          snippet.destroy
+        end
+
+        def allow_local_requests?
+          Gitlab::CurrentSettings.allow_local_requests_from_web_hooks_and_services?
+        end
+
+        def fail_and_track(snippet)
+          remove_snippet_and_repository(snippet)
+
+          ServiceResponse.error(message: 'Snippet max file count exceeded').track_exception(as: FileCountLimitError)
+        end
+      end
+    end
+  end
+end