refactor: split EmailHandler in 3

InvalidEmailHandler - handle emails with an invalid format
LocalEmailHandler   - handle emails on the local domain
EmailHandler        - handle all other emails by using hkp

This is a preparation to add leap provider email lookup and remove
hkp eventually. But for now we keep the behaviour the same and only
refactor.

4 files changed, 55 insertions, 36 deletions

diff --git a/lib/nickserver/dispatcher.rb b/lib/nickserver/dispatcher.rb
index 833a2ad..8bcfd05 100644
--- a/lib/nickserver/dispatcher.rb
+++ b/lib/nickserver/dispatcher.rb
@@ -14,6 +14,8 @@
 #
 
 require 'nickserver/request'
+require 'nickserver/request_handlers/invalid_email_handler'
+require 'nickserver/request_handlers/local_email_handler'
 require 'nickserver/request_handlers/email_handler'
 require 'nickserver/request_handlers/fingerprint_handler'
 
@@ -45,6 +47,8 @@ module Nickserver
 
     def handler_chain
       [
+        RequestHandlers::InvalidEmailHandler.new,
+        RequestHandlers::LocalEmailHandler.new,
         RequestHandlers::EmailHandler.new,
         RequestHandlers::FingerprintHandler.new,
         Proc.new { Nickserver::Response.new(404, "Not Found\n") }
diff --git a/lib/nickserver/request_handlers/email_handler.rb b/lib/nickserver/request_handlers/email_handler.rb
index b163b27..96fcaf3 100644
--- a/lib/nickserver/request_handlers/email_handler.rb
+++ b/lib/nickserver/request_handlers/email_handler.rb
@@ -1,7 +1,5 @@
 require 'nickserver/email_address'
-require 'nickserver/error_response'
 require 'nickserver/hkp/source'
-require 'nickserver/couch_db/source'
 
 module Nickserver
   module RequestHandlers
@@ -9,46 +7,16 @@ module Nickserver
 
       def call(request)
         return unless request.email
-        handle_request(request)
-      end
-
-      protected
-
-      def handle_request(request)
         email = EmailAddress.new(request.email)
-        if email.invalid?
-          ErrorResponse.new("Not a valid address")
-        else
-          send_key(email, request)
-        end
-      end
-
-      def send_key(email, request)
-        if local_address?(email, request)
-          source = Nickserver::CouchDB::Source.new
-        else
-          source = Nickserver::Hkp::Source.new
-        end
         source.query(email)
-      rescue MissingHostHeader
-        ErrorResponse.new("HTTP request must include a Host header.")
       end
 
-      #
-      # Return true if the user address is for a user of this service provider.
-      # e.g. if the provider is example.org, then alice@example.org returns true.
-      #
-      # If 'domain' is not configured, we rely on the Host header of the HTTP request.
-      #
-      def local_address?(email, request)
-        domain = Config.domain || request.domain
-        raise MissingHostHeader if domain == ''
-        email.domain? domain
-      end
-    end
+      protected
 
+      def source
+        Nickserver::Hkp::Source.new
+      end
 
-    class MissingHostHeader < StandardError
     end
   end
 end
diff --git a/lib/nickserver/request_handlers/invalid_email_handler.rb b/lib/nickserver/request_handlers/invalid_email_handler.rb
new file mode 100644
index 0000000..eaf8156
--- /dev/null
+++ b/lib/nickserver/request_handlers/invalid_email_handler.rb
@@ -0,0 +1,15 @@
+require 'nickserver/email_address'
+require 'nickserver/error_response'
+
+module Nickserver
+  module RequestHandlers
+    class InvalidEmailHandler
+      def call(request)
+        return unless request.email
+        email = EmailAddress.new(request.email)
+        ErrorResponse.new("Not a valid address") if email.invalid?
+      end
+
+    end
+  end
+end
diff --git a/lib/nickserver/request_handlers/local_email_handler.rb b/lib/nickserver/request_handlers/local_email_handler.rb
new file mode 100644
index 0000000..1f2abc2
--- /dev/null
+++ b/lib/nickserver/request_handlers/local_email_handler.rb
@@ -0,0 +1,32 @@
+require 'nickserver/email_address'
+require 'nickserver/error_response'
+require 'nickserver/couch_db/source'
+
+module Nickserver
+  module RequestHandlers
+    class LocalEmailHandler
+
+      def call(request)
+        return nil unless request.email
+        domain = Config.domain || request.domain
+        return missing_domain_response if domain.nil? || domain == ''
+        email = EmailAddress.new(request.email)
+        return nil unless email.domain?(domain)
+        source.query email
+      end
+
+      protected
+
+      attr_reader :domain
+
+      def source
+        Nickserver::CouchDB::Source.new
+      end
+
+      def missing_domain_response
+        ErrorResponse.new "HTTP request must include a Host header."
+      end
+
+    end
+  end
+end