Add support to parse RFC 7033 WebFinger JSON

Also:
* Fix date format when generating JRD document
* Sort elements always with the same order

lib/diaspora_federation/discovery/web_finger.rb

@@ -119,8 +119,20 @@ module DiasporaFederation
       # @return [WebFinger] WebFinger instance
       # @raise [InvalidData] if the given XML string is invalid or incomplete
       def self.from_xml(webfinger_xml)
-        data = parse_xml_and_validate(webfinger_xml)
+        from_hash(parse_xml_and_validate(webfinger_xml))
+      end
 
+      # Creates a WebFinger instance from the given JSON string
+      # @param [String] webfinger_json WebFinger JSON string
+      # @return [WebFinger] WebFinger instance
+      def self.from_json(webfinger_json)
+        from_hash(XrdDocument.json_data(webfinger_json))
+      end
+
+      # Creates a WebFinger instance from the given data
+      # @param [Hash] data WebFinger data hash
+      # @return [WebFinger] WebFinger instance
+      def self.from_hash(data)
         links = data[:links]
 
         new(

lib/diaspora_federation/discovery/xrd_document.rb

@@ -83,10 +83,10 @@ module DiasporaFederation
       def to_json
         {
           subject:    subject,
-          expires:    expires,
+          expires:    (expires.strftime(DATETIME_FORMAT) if expires.instance_of?(DateTime)),
           aliases:    (aliases if aliases.any?),
-          links:      (links if links.any?),
-          properties: (properties if properties.any?)
+          properties: (properties if properties.any?),
+          links:      (links if links.any?)
         }.reject {|_, v| v.nil? }
       end
 
@@ -115,6 +115,27 @@ module DiasporaFederation
         end
       end
 
+      # Parse the JRD document from the given string and create a hash containing
+      # the extracted data with symbolized keys.
+      #
+      # @param [String] jrd_doc JSON string
+      # @return [Hash] extracted data
+      # @raise [InvalidDocument] if the JRD is malformed
+      def self.json_data(jrd_doc)
+        json_hash = JSON.parse(jrd_doc)
+
+        {
+          subject:    json_hash["subject"],
+          expires:    (DateTime.strptime(json_hash["expires"], DATETIME_FORMAT) if json_hash.key?("expires")),
+          aliases:    json_hash["aliases"],
+          properties: json_hash["properties"],
+          links:      symbolize_keys_for_links(json_hash["links"])
+        }.reject {|_, v| v.nil? }
+      rescue JSON::JSONError => e
+        raise InvalidDocument,
+              "Not a JRD document: #{e.class}: #{e.message[0..255].encode(Encoding.default_external, undef: :replace)}"
+      end
+
       private
 
       attr_reader :expires
@@ -180,6 +201,17 @@ module DiasporaFederation
         end
         data[:links] = links unless links.empty?
       end
+
+      # symbolize link keys from JSON hash, but only convert known keys
+      private_class_method def self.symbolize_keys_for_links(links)
+        links.map do |link|
+          {}.tap do |hash|
+            LINK_ATTRS.each do |attr|
+              hash[attr] = link[attr.to_s] if link.key?(attr.to_s)
+            end
+          end
+        end
+      end
     end
   end
 end

spec/lib/diaspora_federation/discovery/web_finger_spec.rb

@@ -39,6 +39,63 @@ XML
 </XRD>
 XML
 
+    let(:json) { <<-JSON }
+{
+  "subject": "#{acct}",
+  "aliases": [
+    "#{person.alias_url}"
+  ],
+  "links": [
+    {
+      "rel": "http://microformats.org/profile/hcard",
+      "type": "text/html",
+      "href": "#{person.hcard_url}"
+    },
+    {
+      "rel": "http://joindiaspora.com/seed_location",
+      "type": "text/html",
+      "href": "#{person.url}"
+    },
+    {
+      "rel": "http://webfinger.net/rel/profile-page",
+      "type": "text/html",
+      "href": "#{person.profile_url}"
+    },
+    {
+      "rel": "http://schemas.google.com/g/2010#updates-from",
+      "type": "application/atom+xml",
+      "href": "#{person.atom_url}"
+    },
+    {
+      "rel": "salmon",
+      "href": "#{person.salmon_url}"
+    },
+    {
+      "rel": "http://ostatus.org/schema/1.0/subscribe",
+      "template": "http://somehost:3000/people?q={uri}"
+    }
+  ]
+}
+JSON
+
+    let(:minimal_json) { <<-JSON }
+{
+  "subject": "#{acct}",
+  "links": [
+    {
+      "rel": "http://microformats.org/profile/hcard",
+      "type": "text/html",
+      "href": "#{person.hcard_url}"
+    },
+    {
+      "rel": "http://joindiaspora.com/seed_location",
+      "type": "text/html",
+      "href": "#{person.url}"
+    }
+  ]
+}
+JSON
+
     let(:string) { "WebFinger:#{data[:acct_uri]}" }
 
     it_behaves_like "an Entity subclass"
@@ -95,66 +152,11 @@ XML
 
       context "json" do
         it "creates a nice JSON document" do
-          json = <<-JSON
-{
-  "subject": "#{acct}",
-  "aliases": [
-    "#{person.alias_url}"
-  ],
-  "links": [
-    {
-      "rel": "http://microformats.org/profile/hcard",
-      "type": "text/html",
-      "href": "#{person.hcard_url}"
-    },
-    {
-      "rel": "http://joindiaspora.com/seed_location",
-      "type": "text/html",
-      "href": "#{person.url}"
-    },
-    {
-      "rel": "http://webfinger.net/rel/profile-page",
-      "type": "text/html",
-      "href": "#{person.profile_url}"
-    },
-    {
-      "rel": "http://schemas.google.com/g/2010#updates-from",
-      "type": "application/atom+xml",
-      "href": "#{person.atom_url}"
-    },
-    {
-      "rel": "salmon",
-      "href": "#{person.salmon_url}"
-    },
-    {
-      "rel": "http://ostatus.org/schema/1.0/subscribe",
-      "template": "http://somehost:3000/people?q={uri}"
-    }
-  ]
-}
-JSON
           wf = Discovery::WebFinger.new(data, aliases: [person.alias_url])
           expect(JSON.pretty_generate(wf.to_json)).to eq(json.strip)
         end
 
         it "creates minimal JSON document" do
-          minimal_json = <<-JSON
-{
-  "subject": "#{acct}",
-  "links": [
-    {
-      "rel": "http://microformats.org/profile/hcard",
-      "type": "text/html",
-      "href": "#{person.hcard_url}"
-    },
-    {
-      "rel": "http://joindiaspora.com/seed_location",
-      "type": "text/html",
-      "href": "#{person.url}"
-    }
-  ]
-}
-JSON
           wf = Discovery::WebFinger.new(minimal_data)
           expect(JSON.pretty_generate(wf.to_json)).to eq(minimal_json.strip)
         end
@@ -167,6 +169,9 @@ JSON
     "#{person.alias_url}",
     "#{person.profile_url}"
   ],
+  "properties": {
+    "http://webfinger.example/ns/name": "Bob Smith"
+  },
   "links": [
     {
       "rel": "http://microformats.org/profile/hcard",
@@ -191,10 +196,7 @@ JSON
       "rel": "http://openid.net/specs/connect/1.0/issuer",
       "href": "https://pod.example.tld/"
     }
-  ],
-  "properties": {
-    "http://webfinger.example/ns/name": "Bob Smith"
-  }
+  ]
 }
 JSON
 
@@ -205,7 +207,7 @@ JSON
     end
 
     context "parsing" do
-      it "reads its own output" do
+      it "reads its own xml output" do
         wf = Discovery::WebFinger.from_xml(xml)
         expect(wf.acct_uri).to eq(acct)
         expect(wf.hcard_url).to eq(person.hcard_url)
@@ -223,6 +225,24 @@ JSON
         expect(wf.seed_url).to eq(person.url)
       end
 
+      it "reads its own json output" do
+        wf = Discovery::WebFinger.from_json(json)
+        expect(wf.acct_uri).to eq(acct)
+        expect(wf.hcard_url).to eq(person.hcard_url)
+        expect(wf.seed_url).to eq(person.url)
+        expect(wf.profile_url).to eq(person.profile_url)
+        expect(wf.atom_url).to eq(person.atom_url)
+        expect(wf.salmon_url).to eq(person.salmon_url)
+        expect(wf.subscribe_url).to eq(person.subscribe_url)
+      end
+
+      it "reads minimal json" do
+        wf = Discovery::WebFinger.from_json(minimal_json)
+        expect(wf.acct_uri).to eq(acct)
+        expect(wf.hcard_url).to eq(person.hcard_url)
+        expect(wf.seed_url).to eq(person.url)
+      end
+
       it "is frozen after parsing" do
         wf = Discovery::WebFinger.from_xml(xml)
         expect(wf).to be_frozen

spec/lib/diaspora_federation/discovery/xrd_document_spec.rb

@@ -15,6 +15,36 @@ module DiasporaFederation
 </XRD>
 XML
 
+    let(:json) { <<-JSON }
+{
+  "subject": "http://blog.example.com/article/id/314",
+  "expires": "2010-01-30T09:30:00Z",
+  "aliases": [
+    "http://blog.example.com/cool_new_thing",
+    "http://blog.example.com/steve/article/7"
+  ],
+  "properties": {
+    "http://blgx.example.net/ns/version": "1.3",
+    "http://blgx.example.net/ns/ext": null
+  },
+  "links": [
+    {
+      "rel": "author",
+      "type": "text/html",
+      "href": "http://blog.example.com/author/steve"
+    },
+    {
+      "rel": "author",
+      "href": "http://example.com/author/john"
+    },
+    {
+      "rel": "copyright",
+      "template": "http://example.com/copyright?id={uri}"
+    }
+  ]
+}
+JSON
+
     let(:data) {
       {
         subject:    "http://blog.example.com/article/id/314",
@@ -72,7 +102,7 @@ XML
 
     describe "#to_json" do
       it "provides the hash for json" do
-        expect(doc.to_json).to eq(data)
+        expect(JSON.pretty_generate(doc.to_json)).to eq(json.strip)
       end
     end
 
@@ -90,5 +120,16 @@ XML
         expect { Discovery::XrdDocument.xml_data("<html></html>") }.to raise_error Discovery::InvalidDocument
       end
     end
+
+    describe ".json_data" do
+      it "reads the json document" do
+        hash = Discovery::XrdDocument.json_data(json)
+        expect(hash).to eq(data)
+      end
+
+      it "raises InvalidDocument when a JSON error occurs" do
+        expect { Discovery::XrdDocument.json_data("foo") }.to raise_error Discovery::InvalidDocument
+      end
+    end
   end
 end