FIX 解决后台管理删除用户后，未删除对应项目，导致项目列表报错问题

app/models/user.rb

@@ -157,6 +157,9 @@ class User < Owner
   has_many :team_users, dependent: :destroy
   has_many :teams, through: :team_users
 
+  has_many :projects, foreign_key: :user_id, dependent: :destroy
+  has_many :repositories, foreign_key: :user_id, dependent: :destroy
+
   # 教学案例
   # has_many :libraries, dependent: :destroy
   has_many :project_trends, dependent: :destroy

app/views/projects/index.json.jbuilder

@@ -25,10 +25,10 @@ json.projects @projects do |project|
       json.image_url render_educoder_avatar_url(project.project_educoder)
     else
       user = project.owner
-      json.type user.type
+      json.type user.try(:type)
       json.name user.try(:show_real_name)
-      json.login user.login
-      json.image_url url_to_avatar(user)
+      json.login user.try(:login)
+      json.image_url user.blank? ? "" : url_to_avatar(user)
     end
   end