add webfinger generator/parser from raven24's gem

.rubocop.yml

@@ -11,13 +11,16 @@ Metrics/LineLength:
 
 # Too short methods lead to extraction of single-use methods, which can make
 # the code easier to read (by naming things), but can also clutter the class
-Metrics/MethodLength: 
+Metrics/MethodLength:
   Max: 20
 
 # The guiding principle of classes is SRP, SRP can't be accurately measured by LoC
 Metrics/ClassLength:
   Max: 1500
 
+Metrics/ModuleLength:
+  Max: 1500
+
 # No space makes the method definition shorter and differentiates
 # from a regular assignment.
 Style/SpaceAroundEqualsInParameterDefault:
@@ -66,7 +69,7 @@ Lint/AssignmentInCondition:
   AllowSafeAssignment: false
 
 # A specialized exception class will take one or more arguments and construct the message from it.
-# So both variants make sense. 
+# So both variants make sense.
 Style/RaiseArgs:
   Enabled: false
 
@@ -124,11 +127,11 @@ Lint/ShadowingOuterLocalVariable:
 
 # Check with yard instead.
 Style/Documentation:
-  Enabled: false 
+  Enabled: false
 
 # This is just silly. Calling the argument `other` in all cases makes no sense.
 Style/OpMethod:
-  Enabled: false 
+  Enabled: false
 
 # There are valid cases, for example debugging Cucumber steps,
 # also they'll fail CI anyway

lib/diaspora_federation/web_finger.rb

@@ -10,3 +10,4 @@ end
 require "diaspora_federation/web_finger/exceptions"
 require "diaspora_federation/web_finger/xrd_document"
 require "diaspora_federation/web_finger/host_meta"
+require "diaspora_federation/web_finger/web_finger"

lib/diaspora_federation/web_finger/web_finger.rb

@@ -0,0 +1,203 @@
+module DiasporaFederation
+  module WebFinger
+    ##
+    # The WebFinger document used for Diaspora* user discovery is based on an older
+    # draft of the specification you can find in the wiki of the "webfinger" project
+    # on {http://code.google.com/p/webfinger/wiki/WebFingerProtocol Google Code}
+    # (from around 2010).
+    #
+    # In the meantime an actual RFC draft has been in development, which should
+    # serve as a base for all future changes of this implementation.
+    #
+    # @example Creating a WebFinger document from account data
+    #   wf = WebFinger.from_account({
+    #     acct_uri:    "acct:user@server.example",
+    #     alias_url:   "https://server.example/people/0123456789abcdef",
+    #     hcard_url:   "https://server.example/hcard/users/user",
+    #     seed_url:    "https://server.example/",
+    #     profile_url: "https://server.example/u/user",
+    #     updates_url: "https://server.example/public/user.atom",
+    #     guid:        "0123456789abcdef",
+    #     pubkey:      "ABCDEF=="
+    #   })
+    #   xml_string = wf.to_xml
+    #
+    # @example Creating a WebFinger instance from an xml document
+    #   wf = WebFinger.from_xml(xml_string)
+    #   ...
+    #   hcard_url = wf.hcard_url
+    #   ...
+    #
+    # @see http://tools.ietf.org/html/draft-jones-appsawg-webfinger "WebFinger" -
+    #   current draft
+    # @see http://code.google.com/p/webfinger/wiki/CommonLinkRelations
+    # @see http://www.iana.org/assignments/link-relations/link-relations.xhtml
+    #   official list of IANA link relations
+    class WebFinger
+      private_class_method :new
+
+      attr_reader :acct_uri, :alias_url, :hcard_url, :seed_url, :profile_url, :updates_url
+
+      # @deprecated Either convert these to +Property+ elements or move to the
+      #   +hCard+, which actually has fields for an +UID+ and +KEY+ defined in
+      #   the +vCard+ specification (will affect older Diaspora* installations).
+      attr_reader :guid, :pubkey
+
+      # +hcard+ link relation
+      REL_HCARD = "http://microformats.org/profile/hcard"
+
+      # +seed_location+ link relation
+      REL_SEED = "http://joindiaspora.com/seed_location"
+
+      # @deprecated This should be a +Property+ or moved to the +hCard+, but +Link+
+      #   is inappropriate according to the specification (will affect older
+      #   Diaspora* installations).
+      # +guid+ link relation
+      REL_GUID = "http://joindiaspora.com/guid"
+
+      # +profile-page+ link relation.
+      # @note This might just as well be an +Alias+ instead of a +Link+.
+      REL_PROFILE = "http://webfinger.net/rel/profile-page"
+
+      # Atom feed link relation
+      REL_UPDATES = "http://schemas.google.com/g/2010#updates-from"
+
+      # @deprecated This should be a +Property+ or moved to the +hcard+, but +Link+
+      #   is inappropriate according to the specification (will affect older
+      #   Diaspora* installations).
+      # +diaspora-public-key+ link relation
+      REL_PUBKEY = "diaspora-public-key"
+
+      # Create the XML string from the current WebFinger instance
+      # @return [String] XML string
+      def to_xml
+        doc = XrdDocument.new
+        doc.subject = @acct_uri
+        doc.aliases << @alias_url
+
+        add_links_to(doc)
+
+        doc.to_xml
+      end
+
+      # Create a WebFinger instance from the given account data Hash.
+      # @param [Hash] data account data
+      # @return [WebFinger] WebFinger instance
+      # @raise [InvalidData] if the given data Hash is invalid or incomplete
+      def self.from_account(data)
+        raise InvalidData unless account_data_complete?(data)
+
+        wf = allocate
+        wf.instance_eval {
+          @acct_uri    = data[:acct_uri]
+          @alias_url   = data[:alias_url]
+          @hcard_url   = data[:hcard_url]
+          @seed_url    = data[:seed_url]
+          @profile_url = data[:profile_url]
+          @updates_url = data[:updates_url]
+
+          # TODO: change me!  #########
+          @guid        = data[:guid]
+          @pubkey      = data[:pubkey]
+          #############################
+        }
+        wf
+      end
+
+      # Create a WebFinger instance from the given XML string.
+      # @param [String] webfinger_xml WebFinger XML string
+      # @return [WebFinger] WebFinger instance
+      def self.from_xml(webfinger_xml)
+        data = XrdDocument.xml_data(webfinger_xml)
+        raise InvalidData unless xml_data_valid?(data)
+
+        hcard, seed, guid, profile, updates, pubkey = parse_links(data)
+
+        wf = allocate
+        wf.instance_eval {
+          @acct_uri    = data[:subject]
+          @alias_url   = data[:aliases].first
+          @hcard_url   = hcard[:href]
+          @seed_url    = seed[:href]
+          @profile_url = profile[:href]
+          @updates_url = updates[:href]
+
+          # TODO: change me!  ##########
+          @guid        = guid[:href]
+          @pubkey      = pubkey[:href]
+          ##############################
+        }
+        wf
+      end
+
+      private
+
+      # Checks the given account data Hash for correct type and completeness.
+      # @param [Hash] data account data
+      # @return [Boolean] validation result
+      def self.account_data_complete?(data)
+        !data.nil? && data.instance_of?(Hash) &&
+        data.key?(:acct_uri) && data.key?(:alias_url) &&
+        data.key?(:hcard_url) && data.key?(:seed_url) &&
+        data.key?(:guid) && data.key?(:profile_url) &&
+        data.key?(:updates_url) && data.key?(:pubkey)
+      end
+      private_class_method :account_data_complete?
+
+      # Does some rudimentary checking on the data Hash produced from parsing the
+      # XML string
+      # @param [Hash] data XML data
+      # @return [Boolean] validation result
+      def self.xml_data_valid?(data)
+        data.key?(:subject) && data.key?(:aliases) && data.key?(:links)
+      end
+      private_class_method :xml_data_valid?
+
+      def add_links_to(doc)
+        doc.links << {rel:  REL_HCARD,
+                      type: "text/html",
+                      href: @hcard_url}
+        doc.links << {rel:  REL_SEED,
+                      type: "text/html",
+                      href: @seed_url}
+
+        # TODO: change me!  ##############
+        doc.links << {rel:  REL_GUID,
+                      type: "text/html",
+                      href: @guid}
+        ##################################
+
+        doc.links << {rel:  REL_PROFILE,
+                      type: "text/html",
+                      href: @profile_url}
+        doc.links << {rel:  REL_UPDATES,
+                      type: "application/atom+xml",
+                      href: @updates_url}
+
+        # TODO: change me!  ##############
+        doc.links << {rel:  REL_PUBKEY,
+                      type: "RSA",
+                      href: @pubkey}
+        ##################################
+      end
+
+      def self.parse_links(data)
+        links = data[:links]
+        hcard   = parse_link(links, REL_HCARD)
+        seed    = parse_link(links, REL_SEED)
+        guid    = parse_link(links, REL_GUID)
+        profile = parse_link(links, REL_PROFILE)
+        updates = parse_link(links, REL_UPDATES)
+        pubkey  = parse_link(links, REL_PUBKEY)
+        raise InvalidData unless [hcard, seed, guid, profile, updates, pubkey].all?
+        [hcard, seed, guid, profile, updates, pubkey]
+      end
+      private_class_method :parse_links
+
+      def self.parse_link(links, rel)
+        links.find {|l| l[:rel] == rel }
+      end
+      private_class_method :parse_link
+    end
+  end
+end

spec/lib/web_finger/web_finger_spec.rb

@@ -0,0 +1,117 @@
+module DiasporaFederation
+  describe WebFinger::WebFinger do
+    acct = "acct:user@pod.example.tld"
+    alias_url = "http://pod.example.tld/"
+    hcard_url = "https://pod.example.tld/hcard/users/abcdef0123456789"
+    seed_url = "https://pod.geraspora.de/"
+    guid = "abcdef0123456789"
+    profile_url = "https://pod.example.tld/u/user"
+    updates_url = "https://pod.example.tld/public/user.atom"
+    pubkey = "AAAAAA=="
+
+    xml = <<-XML
+<?xml version="1.0" encoding="UTF-8"?>
+<XRD xmlns="http://docs.oasis-open.org/ns/xri/xrd-1.0">
+  <Subject>#{acct}</Subject>
+  <Alias>#{alias_url}</Alias>
+  <Link rel="http://microformats.org/profile/hcard" type="text/html" href="#{hcard_url}"/>
+  <Link rel="http://joindiaspora.com/seed_location" type="text/html" href="#{seed_url}"/>
+  <Link rel="http://joindiaspora.com/guid" type="text/html" href="#{guid}"/>
+  <Link rel="http://webfinger.net/rel/profile-page" type="text/html" href="#{profile_url}"/>
+  <Link rel="http://schemas.google.com/g/2010#updates-from" type="application/atom+xml" href="#{updates_url}"/>
+  <Link rel="diaspora-public-key" type="RSA" href="#{pubkey}"/>
+</XRD>
+XML
+
+    it "must not create blank instances" do
+      expect { WebFinger::WebFinger.new }.to raise_error
+    end
+
+    context "generation" do
+      it "creates a nice XML document" do
+        wf = WebFinger::WebFinger.from_account(
+          acct_uri:    acct,
+          alias_url:   alias_url,
+          hcard_url:   hcard_url,
+          seed_url:    seed_url,
+          profile_url: profile_url,
+          updates_url: updates_url,
+          guid:        guid,
+          pubkey:      pubkey
+        )
+        expect(wf.to_xml).to eq(xml)
+      end
+
+      it "fails if some params are missing" do
+        expect {
+          WebFinger::WebFinger.from_account(
+            acct_uri:  acct,
+            alias_url: alias_url,
+            hcard_url: hcard_url
+          )
+        }.to raise_error(WebFinger::InvalidData)
+      end
+
+      it "fails if nothing was given" do
+        expect { WebFinger::WebFinger.from_account({}) }.to raise_error(WebFinger::InvalidData)
+      end
+    end
+
+    context "parsing" do
+      it "reads its own output" do
+        wf = WebFinger::WebFinger.from_xml(xml)
+        expect(wf.acct_uri).to eq(acct)
+        expect(wf.alias_url).to eq(alias_url)
+        expect(wf.hcard_url).to eq(hcard_url)
+        expect(wf.seed_url).to eq(seed_url)
+        expect(wf.profile_url).to eq(profile_url)
+        expect(wf.updates_url).to eq(updates_url)
+
+        expect(wf.guid).to eq(guid)
+        expect(wf.pubkey).to eq(pubkey)
+      end
+
+      it "reads old-style XML" do
+        historic_xml = <<-XML
+<?xml version="1.0" encoding="UTF-8"?>
+<XRD xmlns="http://docs.oasis-open.org/ns/xri/xrd-1.0">
+  <Subject>#{acct}</Subject>
+  <Alias>#{alias_url}</Alias>
+  <Link rel="http://microformats.org/profile/hcard" type="text/html" href="#{hcard_url}"/>
+  <Link rel="http://joindiaspora.com/seed_location" type = "text/html" href="#{seed_url}"/>
+  <Link rel="http://joindiaspora.com/guid" type = "text/html" href="#{guid}"/>
+
+  <Link rel="http://webfinger.net/rel/profile-page" type="text/html" href="#{profile_url}"/>
+  <Link rel="http://schemas.google.com/g/2010#updates-from" type="application/atom+xml" href="#{updates_url}"/>
+
+  <Link rel="diaspora-public-key" type = "RSA" href="#{pubkey}"/>
+</XRD>
+XML
+
+        wf = WebFinger::WebFinger.from_xml(historic_xml)
+        expect(wf.acct_uri).to eq(acct)
+        expect(wf.alias_url).to eq(alias_url)
+        expect(wf.hcard_url).to eq(hcard_url)
+        expect(wf.seed_url).to eq(seed_url)
+        expect(wf.profile_url).to eq(profile_url)
+        expect(wf.updates_url).to eq(updates_url)
+
+        expect(wf.guid).to eq(guid)
+        expect(wf.pubkey).to eq(pubkey)
+      end
+
+      it "fails if the document is empty" do
+        invalid_xml = <<XML
+<?xml version="1.0" encoding="UTF-8"?>
+<XRD xmlns="http://docs.oasis-open.org/ns/xri/xrd-1.0">
+</XRD>
+XML
+        expect { WebFinger::WebFinger.from_xml(invalid_xml) }.to raise_error(WebFinger::InvalidData)
+      end
+
+      it "fails if the document is not XML" do
+        expect { WebFinger::WebFinger.from_xml("") }.to raise_error(WebFinger::InvalidDocument)
+      end
+    end
+  end
+end