* lib/webrick: Add documentation for WEBrick::HTTPAuth

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@31505 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,7 @@
+Wed May 11 08:36:38 2011  Eric Hodel  <drbrain@segment7.net>
+
+	* lib/webrick: Add documentation for WEBrick::HTTPAuth
+
 Wed May 11 03:06:35 2011  Eric Hodel  <drbrain@segment7.net>
 
 	* lib/rss.rb: Add documentation for RSS.  Patch by Steve Klabnik.

lib/webrick.rb

@@ -133,6 +133,12 @@
 # +:ProxyContentHandler+ callback which will be invoked with the request and
 # respone after the remote content has been fetched.
 #
+# == Basic and Digest authentication
+#
+# WEBrick provides both Basic and Digest authentication for regular and proxy
+# servers.  See WEBrick::HTTPAuth, WEBrick::HTTPAuth::BasicAuth and
+# WEBrick::HTTPAuth::DigestAuth.
+#
 # == WEBrick as a Production Web Server
 #
 # WEBrick can be run as a production server for small loads.

lib/webrick/httpauth.rb

@@ -15,10 +15,46 @@ require 'webrick/httpauth/htdigest'
 require 'webrick/httpauth/htgroup'
 
 module WEBrick
+
+  ##
+  # HTTPAuth provides both basic and digest authentication.
+  #
+  # To enable authentication for requests in WEBrick you will need a user
+  # database and an authenticator.  To start, here's an Htpasswd database for
+  # use with a DigestAuth authenticator:
+  #
+  #   config = { :Realm => 'DigestAuth example realm' }
+  #
+  #   htpasswd = WEBrick::HTTPAuth::Htpasswd.new 'my_password_file'
+  #   htpasswd.auth_type = WEBrick::HTTPAuth::DigestAuth
+  #   htpasswd.set_passwd config[:Realm], 'username', 'password'
+  #   htpasswd.flush
+  #
+  # The +:Realm+ is used to provide different access to different groups
+  # across several resources on a server.  Typically you'll need only one
+  # realm for a server.
+  #
+  # This database can be used to create an authenticator:
+  #
+  #   config[:UserDB] = htpasswd
+  #
+  #   digest_auth = WEBrick::HTTPAuth::DigestAuth.new config
+  #
+  # To authenticate a request call #authenticate with a request and response
+  # object in a servlet:
+  #
+  #   def do_GET req, res
+  #     @authenticator.authenticate req, res
+  #   end
+  #
+  # For digest authentication the authenticator must not be created every
+  # request, it must be passed in as an option via WEBrick::HTTPServer#mount.
+
   module HTTPAuth
     module_function
 
-    def _basic_auth(req, res, realm, req_field, res_field, err_type, block)
+    def _basic_auth(req, res, realm, req_field, res_field, err_type,
+                    block) # :nodoc:
       user = pass = nil
       if /^Basic\s+(.*)/o =~ req[req_field]
         userpass = $1
@@ -32,12 +68,26 @@ module WEBrick
       raise err_type
     end
 
-    def basic_auth(req, res, realm, &block)
+    ##
+    # Simple wrapper for providing basic authentication for a request.  When
+    # called with a request +req+, response +res+, authentication +realm+ and
+    # +block+ the block will be called with a +username+ and +password+.  If
+    # the block returns true the request is allowed to continue, otherwise an
+    # HTTPStatus::Unauthorized error is raised.
+
+    def basic_auth(req, res, realm, &block) # :yield: username, password
       _basic_auth(req, res, realm, "Authorization", "WWW-Authenticate",
                   HTTPStatus::Unauthorized, block)
     end
 
-    def proxy_basic_auth(req, res, realm, &block)
+    ##
+    # Simple wrapper for providing basic authentication for a proxied request.
+    # When called with a request +req+, response +res+, authentication +realm+
+    # and +block+ the block will be called with a +username+ and +password+.
+    # If the block returns true the request is allowed to continue, otherwise
+    # an HTTPStatus::ProxyAuthenticationRequired error is raised.
+
+    def proxy_basic_auth(req, res, realm, &block) # :yield: username, password
       _basic_auth(req, res, realm, "Proxy-Authorization", "Proxy-Authenticate",
                   HTTPStatus::ProxyAuthenticationRequired, block)
     end

lib/webrick/httpauth/authenticator.rb

@@ -9,17 +9,43 @@
 
 module WEBrick
   module HTTPAuth
+
+    ##
+    # Module providing generic support for both Digest and Basic
+    # authentication schemes.
+
     module Authenticator
+
       RequestField      = "Authorization"
       ResponseField     = "WWW-Authenticate"
       ResponseInfoField = "Authentication-Info"
       AuthException     = HTTPStatus::Unauthorized
-      AuthScheme        = nil # must override by the derived class
 
-      attr_reader :realm, :userdb, :logger
+      ##
+      # Method of authentication, must be overriden by the including class
+
+      AuthScheme        = nil
+
+      ##
+      # The realm this authenticator covers
+
+      attr_reader :realm
+
+      ##
+      # The user database for this authenticator
+
+      attr_reader :userdb
+
+      ##
+      # The logger for this authenticator
+
+      attr_reader :logger
 
       private
 
+      ##
+      # Initializes the authenticator from +config+
+
       def check_init(config)
         [:UserDB, :Realm].each{|sym|
           unless config[sym]
@@ -37,6 +63,9 @@ module WEBrick
         @auth_scheme     = self::class::AuthScheme
       end
 
+      ##
+      # Ensures +req+ has credentials that can be authenticated.
+
       def check_scheme(req)
         unless credentials = req[@request_field]
           error("no credentials in the request.")
@@ -69,6 +98,10 @@ module WEBrick
       end
     end
 
+    ##
+    # Module providing generic support for both Digest and Basic
+    # authentication schemes for proxies.
+
     module ProxyAuthenticator
       RequestField  = "Proxy-Authorization"
       ResponseField = "Proxy-Authenticate"

lib/webrick/httpauth/basicauth.rb

@@ -13,11 +13,32 @@ require 'webrick/httpauth/authenticator'
 
 module WEBrick
   module HTTPAuth
+
+    ##
+    # Basic Authentication for WEBrick
+    #
+    # Use this class to add basic authentication to a WEBrick servlet.
+    #
+    # Here is an example of how to set up a BasicAuth:
+    #
+    #   config = { :Realm => 'BasicAuth example realm' }
+    #
+    #   htpasswd = WEBrick::HTTPAuth::Htpasswd.new 'my_password_file'
+    #   htpasswd.set_passwd config[:Realm], 'username', 'password'
+    #   htpasswd.flush
+    #
+    #   config[:UserDB] = htpasswd
+    #
+    #   basic_auth = WEBrick::HTTPAuth::BasicAuth.new config
+
     class BasicAuth
       include Authenticator
 
       AuthScheme = "Basic"
 
+      ##
+      # Used by UserDB to create a basic password entry
+
       def self.make_passwd(realm, user, pass)
         pass ||= ""
         pass.crypt(Utils::random_string(2))
@@ -25,11 +46,26 @@ module WEBrick
 
       attr_reader :realm, :userdb, :logger
 
+      ##
+      # Creates a new BasicAuth instance.
+      #
+      # See WEBrick::Config::BasicAuth for default configuration entries
+      #
+      # You must supply the following configuration entries:
+      #
+      # :Realm:: The name of the realm being protected.
+      # :UserDB:: A database of usernames and passwords.
+      #           A WEBrick::HTTPAuth::Htpasswd instance should be used.
+
       def initialize(config, default=Config::BasicAuth)
         check_init(config)
         @config = default.dup.update(config)
       end
 
+      ##
+      # Authenticates a +req+ and returns a 401 Unauthorized using +res+ if
+      # the authentication was not correct.
+
       def authenticate(req, res)
         unless basic_credentials = check_scheme(req)
           challenge(req, res)
@@ -52,12 +88,19 @@ module WEBrick
         req.user = userid
       end
 
+      ##
+      # Returns a challenge response which asks for for authentication
+      # information
+
       def challenge(req, res)
         res[@response_field] = "#{@auth_scheme} realm=\"#{@realm}\""
         raise @auth_exception
       end
     end
 
+    ##
+    # Basic authentication for proxy servers.  See BasicAuth for details.
+
     class ProxyBasicAuth < BasicAuth
       include ProxyAuthenticator
     end

lib/webrick/httpauth/digestauth.rb

@@ -29,12 +29,11 @@ module WEBrick
     #
     #   config = { :Realm => 'DigestAuth example realm' }
     #
-    #   htpasswd = WEBrick::HTTPAuth::Htpasswd.new 'my_password_file'
+    #   htdigest = WEBrick::HTTPAuth::Htdigest.new 'my_password_file'
-    #   htpasswd.auth_type = WEBrick::HTTPAuth::DigestAuth
+    #   htdigest.set_passwd config[:Realm], 'username', 'password'
-    #   htpasswd.set_passwd config[:Realm], 'username', 'password'
+    #   htdigest.flush
-    #   htpasswd.flush
     #
-    #   config[:UserDB] = htpasswd
+    #   config[:UserDB] = htdigest
     #
     #   digest_auth = WEBrick::HTTPAuth::DigestAuth.new config
     #
@@ -51,7 +50,7 @@ module WEBrick
       attr_reader :algorithm, :qop
 
       ##
-      # Used by UserDB to create a password entry
+      # Used by UserDB to create a digest password entry
 
       def self.make_passwd(realm, user, pass)
         pass ||= ""
@@ -68,8 +67,8 @@ module WEBrick
       # You must supply the following configuration entries:
       #
       # :Realm:: The name of the realm being protected.
-      # :UserDB:: A database of usernames and passwords.  See Htpasswd,
+      # :UserDB:: A database of usernames and passwords.
-      #           Htdigest, Htgroup
+      #           A WEBrick::HTTPAuth::Htdigest instance should be used.
 
       def initialize(config, default=Config::DigestAuth)
         check_init(config)
@@ -381,6 +380,9 @@ module WEBrick
 
     end
 
+    ##
+    # Digest authentication for proxy servers.  See DigestAuth for details.
+
     class ProxyDigestAuth < DigestAuth
       include ProxyAuthenticator
 

lib/webrick/httpauth/htdigest.rb

@@ -13,9 +13,26 @@ require 'tempfile'
 
 module WEBrick
   module HTTPAuth
+
+    ##
+    # Htdigest accesses apache-compatible digest password files.  Passwords are
+    # matched to a realm where they are valid.  For security, the path for a
+    # digest password database should be stored outside of the paths available
+    # to the HTTP server.
+    #
+    # Htdigest is intended for use with WEBrick::HTTPAuth::DigestAuth and
+    # stores passwords using cryptographic hashes.
+    #
+    #   htpasswd = WEBrick::HTTPAuth::Htdigest.new 'my_password_file'
+    #   htpasswd.set_passwd 'my realm', 'username', 'password'
+    #   htpasswd.flush
+
     class Htdigest
       include UserDB
 
+      ##
+      # Open a digest password database at +path+
+
       def initialize(path)
         @path = path
         @mtime = Time.at(0)
@@ -26,6 +43,9 @@ module WEBrick
         reload
       end
 
+      ##
+      # Reloads passwords from the database
+
       def reload
         mtime = File::mtime(@path)
         if mtime > @mtime
@@ -44,6 +64,10 @@ module WEBrick
         end
       end
 
+      ##
+      # Flush the password database.  If +output+ is given the database will
+      # be written there instead of to the original path.
+
       def flush(output=nil)
         output ||= @path
         tmp = Tempfile.new("htpasswd", File::dirname(output))
@@ -56,6 +80,10 @@ module WEBrick
         end
       end
 
+      ##
+      # Retrieves a password from the database for +user+ in +realm+.  If
+      # +reload_db+ is true the database will be reloaded first.
+
       def get_passwd(realm, user, reload_db)
         reload() if reload_db
         if hash = @digest[realm]
@@ -63,6 +91,9 @@ module WEBrick
         end
       end
 
+      ##
+      # Sets a password in the database for +user+ in +realm+ to +pass+.
+
       def set_passwd(realm, user, pass)
         @mutex.synchronize{
           unless @digest[realm]
@@ -72,13 +103,19 @@ module WEBrick
         }
       end
 
+      ##
+      # Removes a password from the database for +user+ in +realm+.
+
       def delete_passwd(realm, user)
         if hash = @digest[realm]
           hash.delete(user)
         end
       end
 
-      def each
+      ##
+      # Iterate passwords in the database.
+
+      def each # :yields: [user, realm, password_hash]
         @digest.keys.sort.each{|realm|
           hash = @digest[realm]
           hash.keys.sort.each{|user|

lib/webrick/httpauth/htgroup.rb

@@ -11,7 +11,26 @@ require 'tempfile'
 
 module WEBrick
   module HTTPAuth
+
+    ##
+    # Htgroup accesses apache-compatible group files.  Htgroup can be used to
+    # provide group-based authentication for users.  Currently Htgroup is not
+    # directly integrated with any authenticators in WEBrick.  For security,
+    # the path for a digest password database should be stored outside of the
+    # paths available to the HTTP server.
+    #
+    # Example:
+    #
+    #   htgroup = WEBrick::HTTPAuth::Htgroup.new 'my_group_file'
+    #   htgroup.add 'superheroes', %w[spiderman batman]
+    #
+    #   htgroup.members('superheroes').include? 'magneto' # => false
+
     class Htgroup
+
+      ##
+      # Open a group database at +path+
+
       def initialize(path)
         @path = path
         @mtime = Time.at(0)
@@ -20,6 +39,9 @@ module WEBrick
         reload
       end
 
+      ##
+      # Reload groups from the database
+
       def reload
         if (mtime = File::mtime(@path)) > @mtime
           @group.clear
@@ -34,6 +56,10 @@ module WEBrick
         end
       end
 
+      ##
+      # Flush the group database.  If +output+ is given the database will be
+      # written there instead of to the original path.
+
       def flush(output=nil)
         output ||= @path
         tmp = Tempfile.new("htgroup", File::dirname(output))
@@ -48,11 +74,17 @@ module WEBrick
         end
       end
 
+      ##
+      # Retrieve the list of members from +group+
+
       def members(group)
         reload
         @group[group] || []
       end
 
+      ##
+      # Add an Array of +members+ to +group+
+
       def add(group, members)
         @group[group] = members(group) | members
       end

lib/webrick/httpauth/htpasswd.rb

@@ -13,9 +13,27 @@ require 'tempfile'
 
 module WEBrick
   module HTTPAuth
+
+    ##
+    # Htpasswd accesses apache-compatible password files.  Passwords are
+    # matched to a realm where they are valid.  For security, the path for a
+    # password database should be stored outside of the paths available to the
+    # HTTP server.
+    #
+    # Htpasswd is intended for use with WEBrick::HTTPAuth::BasicAuth.
+    #
+    # To create an Htpasswd database with a single user:
+    #
+    #   htpasswd = WEBrick::HTTPAuth::Htpasswd.new 'my_password_file'
+    #   htpasswd.set_passwd 'my realm', 'username', 'password'
+    #   htpasswd.flush
+
     class Htpasswd
       include UserDB
 
+      ##
+      # Open a password database at +path+
+
       def initialize(path)
         @path = path
         @mtime = Time.at(0)
@@ -25,6 +43,9 @@ module WEBrick
         reload
       end
 
+      ##
+      # Reload passwords from the database
+
       def reload
         mtime = File::mtime(@path)
         if mtime > @mtime
@@ -48,6 +69,10 @@ module WEBrick
         end
       end
 
+      ##
+      # Flush the password database.  If +output+ is given the database will
+      # be written there instead of to the original path.
+
       def flush(output=nil)
         output ||= @path
         tmp = Tempfile.new("htpasswd", File::dirname(output))
@@ -60,20 +85,33 @@ module WEBrick
         end
       end
 
+      ##
+      # Retrieves a password from the database for +user+ in +realm+.  If
+      # +reload_db+ is true the database will be reloaded first.
+
       def get_passwd(realm, user, reload_db)
         reload() if reload_db
         @passwd[user]
       end
 
+      ##
+      # Sets a password in the database for +user+ in +realm+ to +pass+.
+
       def set_passwd(realm, user, pass)
         @passwd[user] = make_passwd(realm, user, pass)
       end
 
+      ##
+      # Removes a password from the database for +user+ in +realm+.
+
       def delete_passwd(realm, user)
         @passwd.delete(user)
       end
 
-      def each
+      ##
+      # Iterate passwords in the database.
+
+      def each # :yields: [user, password]
         @passwd.keys.sort.each{|user|
           yield([user, @passwd[user]])
         }

lib/webrick/httpauth/userdb.rb

@@ -9,19 +9,42 @@
 
 module WEBrick
   module HTTPAuth
+
+    ##
+    # User database mixin for HTTPAuth.  This mixin dispatches user record
+    # access to the underlying auth_type for this database.
+
     module UserDB
-      attr_accessor :auth_type # BasicAuth or DigestAuth
+
+      ##
+      # The authentication type.
+      #
+      # WEBrick::HTTPAuth::BasicAuth or WEBrick::HTTPAuth::DigestAuth are
+      # built-in.
+
+      attr_accessor :auth_type
+
+      ##
+      # Creates an obscured password in +realm+ with +user+ and +password+
+      # using the auth_type of this database.
 
       def make_passwd(realm, user, pass)
         @auth_type::make_passwd(realm, user, pass)
       end
 
+      ##
+      # Sets a password in +realm+ with +user+ and +password+ for the
+      # auth_type of this database.
+
       def set_passwd(realm, user, pass)
         self[user] = pass
       end
 
+      ##
+      # Retrieves a password in +realm+ for +user+ for the auth_type of this
+      # database.  +reload_db+ is a dummy value.
+
       def get_passwd(realm, user, reload_db=false)
-        # reload_db is dummy
         make_passwd(realm, user, self[user])
       end
     end