Allow disable login

src/config.cr

@@ -20,6 +20,8 @@ class Config
   property plugin_path : String = File.expand_path "~/mango/plugins",
     home: true
   property download_timeout_seconds : Int32 = 30
+  property disable_login = false
+  property default_username = ""
   property mangadex = Hash(String, String | Int32).new
 
   @[YAML::Field(ignore: true)]
@@ -85,5 +87,9 @@ class Config
     unless base_url.ends_with? "/"
       @base_url += "/"
     end
+    if disable_login && default_username.empty?
+      raise "Login is disabled, but default username is not set. " \
+            "Please set a default username"
+    end
   end
 end

src/handlers/auth_handler.cr

@@ -68,13 +68,14 @@ class AuthHandler < Kemal::Handler
       return call_next(env)
     end
 
-    unless validate_token env
+    unless validate_token(env) || Config.current.disable_login
       env.session.string "callback", env.request.path
       return redirect env, "/login"
     end
 
     if request_path_startswith env, ["/admin", "/api/admin", "/download"]
-      unless validate_token_admin env
+      unless validate_token_admin(env) ||
+             Storage.default.username_is_admin Config.current.default_username
         env.response.status_code = 403
       end
     end

src/storage.cr

@@ -64,6 +64,14 @@ class Storage
 
           init_admin if init_user
         end
+
+        # Verifies that the default username in config is valid
+        if Config.current.disable_login
+          username = Config.current.default_username
+          unless username_exists username
+            raise "Default username #{username} does not exist"
+          end
+        end
       end
       unless @auto_close
         @db = DB.open "sqlite3://#{@path}"
@@ -90,6 +98,28 @@ class Storage
     end
   end
 
+  def username_exists(username)
+    exists = false
+    MainFiber.run do
+      get_db do |db|
+        exists = db.query_one("select count(*) from users where " \
+                              "username = (?)", username, as: Int32) > 0
+      end
+    end
+    exists
+  end
+
+  def username_is_admin(username)
+    is_admin = false
+    MainFiber.run do
+      get_db do |db|
+        is_admin = db.query_one("select admin from users where " \
+                                "username = (?)", username, as: Int32) > 0
+      end
+    end
+    is_admin
+  end
+
   def verify_user(username, password)
     out_token = nil
     MainFiber.run do

src/util/web.cr

@@ -7,6 +7,10 @@ macro layout(name)
     if token = env.session.string? "token"
       is_admin = @context.storage.verify_admin token
     end
+    if Config.current.disable_login
+      is_admin = @context.storage.
+        username_is_admin Config.current.default_username
+    end
     page = {{name}}
     render "src/views/#{{{name}}}.html.ecr", "src/views/layout.html.ecr"
   rescue e
@@ -21,10 +25,16 @@ macro send_img(env, img)
 end
 
 macro get_username(env)
-  # if the request gets here, it has gone through the auth handler, and
-  #   we can be sure that a valid token exists, so we can use not_nil! here
-  token = env.session.string "token"
-  (@context.storage.verify_token token).not_nil!
+  begin
+    token = env.session.string "token"
+    (@context.storage.verify_token token).not_nil!
+  rescue e
+    if Config.current.disable_login
+      Config.current.default_username
+    else
+      raise e
+    end
+  end
 end
 
 def send_json(env, json)