module RSence module Plugins # The Plugin__ is actually available as +Plugin+ from plugin bundles using the {RSence::Plugins::Plugin} class mimic method. # # The Plugin class is the base class for extending server logic. A single Plugin instance serves the requests of all sessions, which makes them very cpu and memory efficient compared to systems, where the server classes are constructed and destructed for each request. # # Plugins are designed to be contained in a plugin directory bundle and to be loaded by the main {PluginManager}, which is also responsible for delegating the events and other calls throughout the system. # # # == Anatomy of a plugin bundle # # First read about the {file:PluginBundles Plugin Bundles}. # # The plugin bundle contains all data needed to run the plugin. Design your plugin without any hard-coded paths, remember that it's intended to be installed by moving or copying the whole plugin into one of the "plugins" directories. Use {#bundle_path} to construct paths. # # The {PluginManager} looks for these bundles and evaluates them into an anonymous +Module+ namespace. The contents of the ruby source file is then responsible for including its libraries, constructing an instance of itself and registering itself as a part of the system. # # Use the {GUIPlugin__ GUIPlugin} class for plugins that handle user interfaces. Use the {Plugin__ Plugin} class for plugin bundles that provide supplemental functionality, value responders and other utilities that supplement the user interface. # # = Extension hooks for server events # These methods are provided as the basic server event hooks: # * {#init +#init+} -- Use instead of +initialize+ # * {#open +#open+} -- Extend to open objects # * {#flush +#flush+} -- Extend to write the state and to flush buffers # * {#close +#close+} -- Extend to close objects # # = Extension hooks for session events # * {#idle +#idle+} -- Extend to implement logic for each client data synchronization and "idle poll" request. # * {#init_ses +#init_ses+} -- Extend to implement logic when a new session is created. A new session is created, when a user enters accesses the server the first time, or the first time after the previous session expired. # * {#restore_ses +#restore_ses+} -- Extend to implement logic when an old session is restored. A session is restored, when the user returns to the page or reloads the page before the session is expired. # # == Extension hooks for session events, If the server is configured to restore and clone previous sessions (default): # When sessions are cloned, the previous session is not invalidated and exists until timing out as a result of the web browser window being closed or client computer losing network connectivity for a certain (configurable) time frame. # * {#cloned_target +#cloned_target+} -- Extend to implement logic in the request when session is a clone of the original session. # * {#cloned_source +#cloned_source+} -- Extend to implement logic in the next request of the original session after it has been cloned. # # == If the server is configured to not clone sessions: # When the user accesses the same page using the same browser (in different tabs or windows), only the most recently restored one is valid, while the previous ones are immediately invalidated. This is a more secure mode of operation, but has several drawback to usability, so it's not enabled by default. # # = Utility methods # These are general utility methods not intended to be extended. # * {#get_ses +#get_ses+} Returns the bundle-specific session Hash. # * {#file_read +#file_read+} Use to read files # * {#yaml_read +#yaml_read+} Use to read yaml data # * {#file_write +#file_write+} Use to write files # * {#bundle_path +#bundle_path+} Use for plugin bundle -specific paths # * {#httime +#httime+} Use for HTTP date/time # # = Client-support # These methods are intended for server-client interaction. Namely, commanding the client. # * {#read_js +#read_js+} Returns a javascript source file. # * {#read_js_once +#read_js_once+} Returns a javascript source file once per session. # * {#values_js +#values_js+} Returns a javascript source snippet containing references to values. # * {#include_js +#include_js+} Tells the client to load a library package. # # = See also # * {file:PluginBundles Plugin Bundles} -- General information about the plugin bundle system # * {file:Values Values} -- General information about the value exchange system # * {file:PluginBundleInfo Plugin Bundle +info.yaml+ files} -- General information about the meta-information files. # * {PluginBase PluginBase} -- The PluginBase module # * {Servlet__ Servlet} -- The Servlet base class # * {GUIPlugin__ GUIPlugin} -- The GUIPlugin base class class Plugin__ include PluginBase # @private Class type identifier for the PluginManager. # @return [:Plugin] def self.bundle_type; :Plugin; end # @return [Symbol] The name of the plugin bundle attr_reader :name # @return [String] The absolute path of the plugin bundle. attr_reader :path # @return [Hash] The {file:PluginBundleInfo meta-information} of the plugin bundle. attr_reader :info # @private State of the plugin. attr_reader :inited # @private The constructor should not be accessed from anywhere else than the PluginManager, which does it automatically. def initialize( bundle_name, bundle_info, bundle_path, plugin_manager ) @inited = false @info = bundle_info @name = bundle_name @path = bundle_path @plugins = plugin_manager register unless @info[:inits_self] end # Extend this method to do any initial tasks before other methods are called. # # By default {#init_values} is called to load the {file:Values +values.yaml+} configuration file. # # @return [nil] # # @see PluginBase#init def init @values = init_values end # Extend this method to do any tasks every time the client makes a request. # # @param [Message] msg The message is supplied by the system. # # @return [nil] def idle( msg ) end # Extend this method to invoke actions, when a new session is created. # # By default {#init_ses_values} is called to initialize values defined in the {file:Values +values.yaml+} configuration file. # # @param [Message] msg The message is supplied by the system. # # @return [nil] def init_ses( msg ) init_ses_values( msg ) end # Extend this method to invoke actions, when a previous session is restored. # # By default +#restore_ses_values+ is called to perform actions on values as defined in the {file:Values +values.yaml+} configuration file. # # @param [Message] msg The message is supplied by the system. # # @return [nil] def restore_ses( msg ) restore_ses_values( msg ) end # Extend this method to invoke actions, when the session is a clone of another session. It's called once, just before {#restore_ses} is called. # # A session is cloned, when a user opens a another browser window or tab, while the previous session is still active. # # @param [Message] msg The message is supplied by the system. # @param [Hash] source_session The actual previous session object, which was used as the source of the clone. # # @return [nil] def cloned_target( msg, source_session ) end # Extend this method to invoke actions, when the session has been cloned to another session. It's called once, just before {#restore_ses} is called on the first request after the cloning happened. # # A session is cloned, when a user opens a another browser window or tab, while the previous session is still active. # # @param [Message] msg The message is supplied by the system. # @param [Hash] target_session The actual cloned session object, which is a copy of the current session. # # @return [nil] def cloned_source( msg, target_sessions ) end # @private This method must be called to register the plugin instance into the system. Otherwise, it's subject to destruction and garbage collection. Use the +name+ parameter to give the (unique) name of your plugin. def register( name=false ) if @inited @plugins.register_alias( @name, name ) else if name name = name.to_s else name = @name end @plugins.register_bundle( self, name ) @inited = true end end def name_with_manager_s if @info[:manager] return "#{@info[:manager].to_s}:#{@name.to_s}" else return @name.to_s end end # This method returns (or creates and returns) the entry in the session based on the name your plugin is registered as. It's advised to use this call instead of manually managing {Message#session msg#session} in most cases. # # Uses the first name registered for the plugin and converts it to a symbol. # # @param [Message] msg The message is supplied by the system. # @param [Symbol] key (optional) returns a ses key, if defined. # # @return [Hash] Plugin-specific session hash def get_ses( msg, key=false ) name_sym = name_with_manager_s.to_sym if msg.class == RSence::Message session = msg.session elsif msg.class == Hash session = msg else warn "Invalid class (#{msg.class}) for get_ses in #{name_sym.inspect}!" return nil end unless session.has_key?( name_sym ) session[ name_sym ] = {} end ses = session[ name_sym ] return ses[key] if key return ses end # Returns an array of type (:js/:coffee/:none), path (string) def guess_js_path( js_name ) has_slash = js_name.include?('/') is_coffee = false is_js = false if has_slash js_fn = js_name.split('/')[-1] else js_fn = js_name end if js_fn.include?('.') js_ext = js_fn.split('.')[-1] if js_ext == 'coffee' is_coffee = true elsif js_ext == 'js' is_js = true end end if has_slash sub_ptah = false else sub_path = 'js' end if is_coffee or is_js path = bundle_path( js_name, sub_path, '.'+js_ext ) found = file_exist?( path ) else path = bundle_path( js_name, sub_path, '.coffee' ) found = file_exist?( path ) if found is_coffee = true else is_js = true path = bundle_path( js_name, sub_path, '.js' ) found = file_exist?( path ) end end foundtype = found ? ( is_coffee ? :coffee : ( is_js ? :js : :none ) ) : :none path = false if foundtype == :none [ foundtype, path ] end # Returns coffee compiled to js def brew_coffee( path ) client_pkg.coffee( file_read( path ) ) end def squeezed_js( path ) client_pkg.squeeze( file_read( path ) ) end # Returns the source code of the javascript file +js_name+ in the 'js' subdirectory of the plugin bundle. Use it to send raw javascript command code to the client. Use {#read_js_once} for libraries. # # @param [String] js_name Javascript source file name without the '.js' suffix. # # @return [String] The source of the file. # @return [false] Returns false, when file was not found. def read_js( js_name ) ( type, path ) = guess_js_path( js_name ) if type == :none warn "File not found: #{js_name}" return '' end return brew_coffee( path ) if type == :coffee # return squeezed_js( path ) if type == :js return file_read( path ) if type == :js warn "read_js: unknown type #{type.inspect}" end # Like {#read_js}, but reads the file only once per session. Use for inclusion of custom library code. # # @param [Message] msg The message is supplied by the system. # @param [String] js_name Javascript source file name without the '.js' suffix. # # @return [String] The source of the file on the first call in a session, or an empty string on the subsequent calls. # @return [false] Returns false, when file was not found. def read_js_once( msg, js_name ) ses = msg.session if not ses.has_key?(:deps) ses[:deps] = [] end ( found, path ) = guess_js_path( js_name ) return false if found == :none unless ses[:deps].include?( path ) ses[:deps].push( path ) return read_js( path ) else return '' end end # Extracts +HValue+ references as javascript from the session Hash. # # @param [Message] msg The message is supplied by the system. # @param [Hash] ses Used for supplying a Hash with the {HValue} instances. It's optional and defaults to the current plugin node in the active session. # # @return [String] A string representing a javascript object similar to the ruby Hash +ses+. # # @example # values_js( msg, get_ses(msg) ) def values_js( msg, ses=false ) # backwards-compatible with pre-1.3 behavior ses = msg if msg.class == Hash # gets the session automatically, if false ses = get_ses( msg ) unless ses js_references = [] ses.each_key do |key_name| if ses[key_name].class == HValue js_references.push( "#{key_name.to_s}:HVM.values['#{ses[key_name].val_id}']" ) end end return "{#{js_references.join(',')}}" end # Tells the js client framework to load a list of pre-packaged client libraries. # # It keeps track of what's loaded, so nothing library loaded twice. # # @param [Message] msg The message is supplied by the system. # @param [Array] dependencies A list of package names. # # @return [nil] # # @example # include_js( msg, [ 'default_theme', 'controls' ] ) # def include_js( msg, dependencies=[] ) ses = msg.session # check, if the session has a dependency array if not ses.has_key?( :deps ) # make an array of dependencies for this session, if not already done ses[:deps] = [] end dependencies = [dependencies] if dependencies.class == String # Check the required dependencies until everything is loaded. dependencies.each do |dependency| unless ses[:deps].include?( dependency ) if RSence.config[:client_pkg][:compound_packages].include?( dependency ) RSence.config[:client_pkg][:compound_packages][dependency].each do |pkg_name| ses[:deps].push( pkg_name ) msg.reply(%{jsLoader.loaded("#{pkg_name}");}) end end ses[:deps].push( dependency ) msg.reply(%{jsLoader.load("#{dependency}");}) end end end # @private Returns a hash with valid symbol keys for +#value_call+. def sanitize_value_call_hash( hash_dirty ) if hash_dirty.class == Symbol return { :method => hash_dirty } elsif hash_dirty.class == String if hash_dirty.include?('.') last_dot_index = hash_dirty.rindex('.') call_plugin = hash_dirty[0..(last_dot_index-1)].to_sym call_method = hash_dirty[(last_dot_index+1)..-1].to_sym return { :method => call_method, :plugin => call_plugin } else return { :method => hash_dirty.to_sym } end end hash_clean = {} hash_dirty.each do | key, value | if key.to_sym == :method hash_clean[:method] = value.to_sym elsif key.to_sym == :plugin hash_clean[:plugin] = value.to_sym elsif key.to_sym == :args if value.class == Array hash_clean[:args] = value else warn "Invalid arguments (#{value.inspect}). Expected Array." end elsif key.to_sym == :uses_msg value == false if value == nil if value.class == TrueClass or value.class == FalseClass hash_clean[:uses_msg] = value else warn "Invalid argument for :uses_msg (#{value.inspect}), expected boolean." end else warn "Undefined value_call key: #{key.inspect}" end end return hash_clean end # @private Returns a sanitized copy of a single responder specification. def sanitize_value_responders( responders_dirty ) if responders_dirty.class != Array responders_dirty = [ responders_dirty ] end responders_clean = [] responders_dirty.each do |responder_dirty| if responder_dirty.class != Hash if responder_dirty.class == Symbol responder_dirty = { :method => responder_dirty } elsif responder_dirty.class == String if responder_dirty.include?('.') last_dot_index = responder_dirty.rindex('.') responder_plugin = responder_dirty[0..(last_dot_index-1)].to_sym responder_method = responder_dirty[(last_dot_index+1)..-1].to_sym responder_dirty = { :method => responder_method, :plugin => responder_plugin } else responder_dirty = { :method => responder_dirty.to_sym } end else warn "Unsupported responder type: #{responder_dirty.inspect}. Skipping.." next end end responder_clean = {} responder_dirty.each do |key, value| if key.to_sym == :method responder_clean[ :method ] = value.to_sym elsif key.to_sym == :plugin responder_clean[ :plugin ] = value.to_sym else warn "Unsupported responder key: #{key.inspect} => #{value.inspect}. Ignoring.." end end if responder_clean.has_key?( :method ) responders_clean.push( responder_clean ) else warn "Responder (#{responder_clean.inspect}) is missing a :method specification. Skipping.." end end return responders_clean end # @private Returns a sanitized copy of a single value item. def sanitize_value_item( value_item_dirty ) unless value_item_dirty.class == Hash value_item_dirty = { :value => value_item_dirty, :restore_default => false } end value_item_clean = { :type => 0 } value_item_dirty.each do | key, value | if key.to_sym == :value or key.to_sym == :data if [Array, Hash, String, TrueClass, FalseClass, Fixnum, Bignum, Float, NilClass].include? value.class value_item_clean[:value] = value else warn "Unsupported value class (#{value.class.inspect}) for value: #{value.inspect}. Using 0 instead." value_item_clean[:value] = 0 end elsif key.to_sym == :value_call or key.to_sym == :call value_item_clean[:value_call] = sanitize_value_call_hash( value ) elsif key.to_sym == :msg_call value_item_clean[:value_call] = sanitize_value_call_hash( value ) value_item_clean[:value_call][:uses_msg] = true unless value_item_clean[:value_call].has_key?(:uses_msg) elsif key.to_sym == :restore_default or key.to_sym == :restore if [TrueClass, FalseClass].include? value.class value_item_clean[:restore_default] = value else warn "Unsupported type of restore (expected true or false): #{value.inspect}. Using true instead." value_item_clean[:restore_default] = true end elsif key.to_sym == :responders or key.to_sym == :responder sanitized_responders = sanitize_value_responders( value ) value_item_clean[:responders] = sanitized_responders unless sanitized_responders.empty? elsif key.to_sym == :type if [0,1,2].include? value value_type = value elsif ['normal',:normal,'push',:push,'pull',:pull].include? value # server concept of push and pull are reversed relative to the client value_type = { 'normal' => 0, :normal => 0, 'pull' => 1, :pull => 1, 'push' => 2, :push => 2 }[value] else warn "Unsupported value type: #{value}" end value_item_clean[:type] = value_type else warn "Unsupported value specification key: #{key.inspect}." end end return value_item_clean end # @private Returns sanitized hash of the structure specified in values.yaml def sanitize_values_yaml( values_path ) values_dirty = yaml_read( values_path ) return false if values_dirty == false if values_dirty.class == Hash values_clean = {} values_dirty.each do |key, value| values_clean[ key.to_sym ] = sanitize_value_item( value ) end return values_clean unless values_clean.empty? elsif values_dirty.class == Array values_clean = [] values_dirty.each do |values_dirty_segment| values_clean_segment = {} values_dirty_segment.each do |key, value| values_clean_segment[ key.to_sym ] = sanitize_value_item( value ) end values_clean.push( values_clean_segment ) end return values_clean unless values_clean.empty? else warn "Unsupported format of #{bundle_path('values.yaml')}, got: #{values_dirty.inspect}, expected Hash or Array." end return false end # @private This method looks looks for a file called "values.yaml" in the plugin's bundle directory. # If this file is found, it loads it for initial value definitions. # These definitions are accessible as the +@values+ attribute. def init_values values_path = bundle_path( 'values.yaml' ) return sanitize_values_yaml( values_path ) end # @private Creates a new instance of HValue, assigns it as +value_name+ into the # session and uses the +value_properties+ Hash to define the default # value and value responders. # # This method is invoked automatically, when handling the properties # of the +values.yaml+ configuration file of a new session. # # It's invoked by +#init_ses+ via +#init_ses_values+. # # Structure of +value_properties+, all top-level items are optional: # # { # # Default value; defaults to 0 # :value => 'foo', # # # A plugin method to call to define the default value instead of the one defined in :value # :value_call => { # :plugin => 'plugin_name', # defaults to the plugin where defined # :method => 'method_name', # mandatory; name of the method to call # :args => [ 1, 'foo', 3 ], # optional, list of parameter values for the :method # :uses_msg => true # defaults to true; when false, doesn't pass the msg as the first parameter # }, # # # Restore the default, when the session is restored; defaults to true # :restore_default => false, # # # List of value responder methods to bind. # :responders => [ # { # :plugin => 'plugin_name', # defaults to the plugin where defined # :method => 'method_name' # mandatory, name of the method to call # }, # # You can supply as many responders as you like: # { :plugin => 'another_plugin', :method => 'another_method' } # ] # } # def init_ses_value( msg, value_name, value_properties ) ses = get_ses( msg ) if value_properties.has_key?(:value_call) default_value = init_value_call( msg, value_properties[:value_call] ) elsif value_properties.has_key?(:value) default_value = value_properties[:value] else default_value = 0 end name = name_with_manager_s ses[value_name] = HValue.new( msg, default_value, { :name => "#{name}.#{value_name}", :type => value_properties[:type] } ) if value_properties.has_key?(:responders) init_responders( msg, ses[value_name], value_properties[:responders] ) end end # @private Initialize a responder for a value. def init_responder( msg, value, responder ) name = name_with_manager_s if responder.has_key?(:plugin) responder_plugin = responder[:plugin] else responder_plugin = name end if responder.has_key?(:method) responder_method = responder[:method] if not value.bound?( responder_plugin, responder_method ) value.bind( responder_plugin, responder[:method] ) end end end # @private Initialize several responders for a value def init_responders( msg, value, responders ) members = value.members release_list = [] members.each_key do |pre_plugin| members[pre_plugin].each do |pre_method| found = false responders.each do |responder| name = name_with_manager_s if responder.has_key?(:plugin) responder_plugin = responder[:plugin] else responder_plugin = name end if responder.has_key?(:method) responder_method = responder[:method] if responder_plugin == pre_plugin and responder_method == pre_method found = true break end end end unless found release_list.push( [ pre_plugin, pre_method ] ) end end end release_list.each do | rel_plugin, rel_method | value.release( rel_plugin, rel_method ) end responders.each do |responder| init_responder( msg, value, responder ) end end # @private Releases all responders of a value def release_responders( msg, value ) members = value.members members.each_key do |responder_plugin| members.each do |responder_method| value.release( responder_plugin, responder_method ) end end end # @private Initializes session values, if the contents of the +values.yaml+ # file is defined in the bundle directory and loaded in +#init_values+. def init_ses_values( msg ) return unless @values if @values.class == Array @values.each do | value_item | value_item.each do | value_name, value_properties | init_ses_value( msg, value_name, value_properties ) end end elsif @values.class == Hash @values.each do | value_name, value_properties | init_ses_value( msg, value_name, value_properties ) end end end # @private Returns a value based on the :method and :plugin members of the # +value_call+ hash. # # The call is made via msg.run if the method is not defined in # the local plugin bundle. # # This method is called from +#init_ses_value+. # # Structure of the +value_call+ Hash: # { :plugin => 'plugin_name', # defaults to the plugin where defined # :method => 'method_name', # mandatory; name of the method to call # :args => [ 1, 'foo', 3 ], # optional, list of parameter values for the :method # :uses_msg => true # defaults to true; when false, doesn't pass the msg as the first parameter # } def init_value_call( msg, value_call ) value_call_method = value_call[:method] if value_call.has_key?(:plugin) value_call_plugin = value_call[:plugin] else value_call_plugin = false end if value_call.has_key?(:args) if value_call.has_key?(:uses_msg) and value_call[:uses_msg] != false if value_call_plugin return msg.run( value_call_plugin, value_call_method, msg, *value_call[:args] ) else return self.method( value_call_method ).call( msg, *value_call[:args] ) end else if value_call_plugin return msg.run( value_call_plugin, value_call_method, *value_call[:args] ) else return self.method( value_call_method ).call( *value_call[:args] ) end end else if value_call.has_key?(:uses_msg) and value_call[:uses_msg] != false if value_call_plugin return msg.run( value_call_plugin, value_call_method, msg ) else return self.method( value_call_method ).call( msg ) end else if value_call_plugin return msg.run( value_call_plugin, value_call_method ) else return self.method( value_call_method ).call( ) end end end end def restore_ses_value( msg, value_name, value_properties ) ses = get_ses( msg ) if ses.has_key?( value_name ) and ses[ value_name ].class == HValue if value_properties.has_key?(:responders) init_responders( msg, ses[value_name], value_properties[:responders] ) else release_responders( msg, ses[value_name] ) end unless value_properties[:restore_default] == false if value_properties.has_key?(:value_call) default_value = init_value_call( msg, value_properties[:value_call] ) elsif value_properties.has_key?(:value) default_value = value_properties[:value] else default_value = 0 end ses[value_name].set( msg, default_value ) end else init_ses_value( msg, value_name, value_properties ) end end # @private Restores session values to default, unless specified otherwise. # # Called from +#restore_ses+ def restore_ses_values( msg ) return unless @values if @values.class == Array @values.each do | value_item | value_item.each do | value_name, value_properties | restore_ses_value( msg, value_name, value_properties ) end end elsif @values.class == Hash @values.each do | value_name, value_properties | restore_ses_value( msg, value_name, value_properties ) end end end end end end