add Callbacks

lib/diaspora_federation.rb

@@ -1,12 +1,20 @@
 require "diaspora_federation/logging"
 
+require "diaspora_federation/callbacks"
 require "diaspora_federation/web_finger"
 
 # diaspora* federation library
 module DiasporaFederation
   extend Logging
 
+  @callbacks = Callbacks.new %i(
+    person_webfinger_fetch
+    person_hcard_fetch
+  )
+
   class << self
+    attr_reader :callbacks
+
     # the pod url
     #
     # @example with uri
@@ -15,124 +23,38 @@ module DiasporaFederation
     #   config.server_uri = AppConfig.pod_uri
     attr_accessor :server_uri
 
-    # the class to use as +Person+
-    #
-    # @example
-    #   config.person_class = Person
-    #
-    # This class must have the following class methods:::
-    #
-    #   +find_local_by_diaspora_handle+:
-    #   This should return a +Person+, which is on this pod and the account is not closed.
-    #
-    #   +find_local_by_guid+:
-    #   This should return a +Person+, which is on this pod and the account is not closed.
-    #
-    # This class must have the following instance methods or attributes:::
-    #
-    #   +diaspora_handle+: the diaspora handle
-    #     "user@server.example"
-    #
-    #   +nickname+: the username on the pod
-    #     "user"
-    #
-    #   +guid+: the guid
-    #     "0123456789abcdef"
-    #
-    #   +serialized_public_key+: the public key of the person (DER-encoded PKCS#1 key)
-    #     "-----BEGIN PUBLIC KEY-----
-    #     ABCDEF==
-    #     -----END PUBLIC KEY-----"
-    #
-    #   +searchable+: if the person is searchable by name
-    #     true
-    #
-    #   +alias_url+: alias url to the profile
-    #     "https://server.example/people/0123456789abcdef"
-    #
-    #   +hcard_url+: url to the hcard
-    #     "https://server.example/hcard/users/0123456789abcdef"
-    #
-    #   +seed_url+: pod url
-    #     "https://server.example/"
-    #
-    #   +profile_url+: url to the profile
-    #     "https://server.example/u/user"
-    #
-    #   +atom_url+: url to the atom rss feed
-    #     "https://server.example/public/user.atom"
-    #
-    #   +salmon_url+: private receive url for salmon
-    #     "https://server.example/receive/users/0123456789abcdef"
-    #
-    #   +photo_large_url+: large photo
-    #     "https://server.example/uploads/l.jpg"
-    #
-    #   +photo_medium_url+: medium photo
-    #     "https://server.example/uploads/m.jpg"
-    #
-    #   +photo_small_url+: small photo
-    #     "https://server.example/uploads/s.jpg"
-    #
-    #   +full_name+: full name
-    #     "User Name"
-    #
-    #   +first_name+: first name
-    #     "User"
-    #
-    #   +last_name+: last name
-    #     "Name"
-    attr_accessor :person_class
-
-    def person_class=(klass)
-      @person_class = klass.nil? ? nil : klass.to_s
-    end
-
-    def person_class
-      const_get(@person_class)
-    end
-
     # configure the federation library
     #
+    # @example
     #   DiasporaFederation.configure do |config|
-    #     config.server_uri = "http://localhost:3000/"
+    #     config.server_uri = URI("http://localhost:3000/")
+    #
+    #     config.define_callbacks do
+    #       # callback configuration
+    #     end
     #   end
     def configure
       yield self
     end
 
+    def define_callbacks(&block)
+      @callbacks.instance_eval(&block)
+    end
+
     # validates if the engine is configured correctly
     #
     # called from after_initialize
     # @raise [ConfigurationError] if the configuration is incomplete or invalid
     def validate_config
-      configuration_error "missing server_uri" unless @server_uri.respond_to? :host
-      validate_class(@person_class, "person_class", %i(
-        find_local_by_diaspora_handle find_local_by_guid
-        diaspora_handle nickname guid serialized_public_key searchable
-        alias_url hcard_url seed_url profile_url atom_url salmon_url
-        photo_large_url photo_medium_url photo_small_url
-        full_name first_name last_name
-      ))
+      configuration_error "Missing server_uri" unless @server_uri.respond_to? :host
+      unless @callbacks.definition_complete?
+        configuration_error "Missing handlers for #{@callbacks.missing_handlers.join(', ')}"
+      end
       logger.info "successfully configured the federation library"
     end
 
     private
 
-    def validate_class(klass, name, methods)
-      configuration_error "missing #{name}" unless klass
-      entity = const_get(klass)
-
-      return logger.warn "table for #{entity} doesn't exist, skip validation" unless entity.table_exists?
-
-      methods.each {|method| entity_respond_to?(entity, name, method) }
-    end
-
-    def entity_respond_to?(entity, name, method)
-      valid = entity.respond_to?(method) || entity.column_names.include?(method.to_s) || entity.method_defined?(method)
-      configuration_error "the configured class #{entity} for #{name} doesn't respond to #{method}" unless valid
-    end
-
     def configuration_error(message)
       logger.fatal("diaspora federation configuration error: #{message}")
       raise ConfigurationError, message

lib/diaspora_federation/callbacks.rb

@@ -0,0 +1,29 @@
+module DiasporaFederation
+  class Callbacks
+    def initialize(events)
+      @events   = events
+      @handlers = {}
+    end
+
+    def on(event, &callback)
+      raise ArgumentError, "Undefined event #{event}" unless @events.include? event
+      raise ArgumentError, "Already defined event #{event}" if @handlers.has_key? event
+
+      @handlers[event] = callback
+    end
+
+    def trigger(event, *args)
+      raise ArgumentError, "Undefined event #{event}" unless @events.include? event
+
+      @handlers[event].call(*args)
+    end
+
+    def definition_complete?
+      missing_handlers.empty?
+    end
+
+    def missing_handlers
+      @events - @handlers.keys
+    end
+  end
+end

spec/lib/diaspora_federation_spec.rb

@@ -2,22 +2,20 @@ module DiasporaFederation
   describe DiasporaFederation do
     context "validate_config" do
       it "should validate the config" do
-        expect(DiasporaFederation).to receive(:validate_class)
+        expect(DiasporaFederation.callbacks).to receive(:definition_complete?).and_return(true)
         DiasporaFederation.validate_config
       end
 
       it "should fails if the server_uri is missing" do
         temp = DiasporaFederation.server_uri
         DiasporaFederation.server_uri = nil
-        expect { DiasporaFederation.validate_config }.to raise_error ConfigurationError
+        expect { DiasporaFederation.validate_config }.to raise_error ConfigurationError, "Missing server_uri"
         DiasporaFederation.server_uri = temp
       end
 
-      it "should fails if the person_class is missing" do
-        temp = DiasporaFederation.person_class
-        DiasporaFederation.person_class = nil
-        expect { DiasporaFederation.validate_config }.to raise_error ConfigurationError
-        DiasporaFederation.person_class = temp
+      it "should validate the config" do
+        expect(DiasporaFederation.callbacks).to receive(:definition_complete?).and_return(false)
+        expect { DiasporaFederation.validate_config }.to raise_error ConfigurationError, "Missing handlers for "
       end
     end
   end

test/dummy/config/initializers/diaspora_federation.rb

@@ -3,6 +3,11 @@ DiasporaFederation.configure do |config|
   # the pod url
   config.server_uri = URI("http://localhost:3000/")
 
-  # the class to be used for a person
-  config.person_class = Person
+  config.define_callbacks do
+    on :person_webfinger_fetch do |handle|
+    end
+
+    on :person_hcard_fetch do |guid|
+    end
+  end
 end