add: readme by filepath

app/services/gitea/repository/readme/dir_service.rb

@@ -0,0 +1,34 @@
+class Gitea::Repository::Readme::DirService < Gitea::ClientService 
+  attr_reader :owner, :repo, :ref, :dir, :token 
+
+  def initialize(owner, repo, dir, ref='', token=nil) 
+    @owner = owner 
+    @repo = repo 
+    @dir = dir
+    @ref = ref
+    @token = token
+  end
+
+  def call 
+    response = get(url, params) 
+    status, message, body = render_response(response)
+    json_format(status, message, body)
+  end
+
+  private 
+  def params
+    Hash.new.merge(token: token, ref: ref) 
+  end
+
+  def url
+    "/repos/#{owner}/#{repo}/readme/#{dir}".freeze 
+  end
+
+  def json_format(status, message, body)
+    case status 
+    when 200 then success(body)
+    when 404 then error(message, 404)
+    else error(message, status)
+    end
+  end
+end