api/v1/versions endpoint

lib/gemstash/gem_source/private_source.rb

@@ -50,6 +50,17 @@ def serve_versions
         halt 403, "Not yet supported"
       end
 
+      def serve_gem_versions(name)
+        authorization.protect(self) do
+          auth.check("fetch") if gemstash_env.config[:protected_fetch]
+          name.slice! ".json"
+          gem = fetch_gem(name)
+          halt 404 unless gem.exist?(:spec)
+          content_type "application/json;charset=UTF-8"
+          fetch_gem_versions(name).to_json
+        end
+      end
+
       def serve_info(name)
         halt 403, "Not yet supported"
       end
@@ -118,6 +129,29 @@ def fetch_gem(gem_full_name)
         halt 403, "That gem has been yanked" unless gem.properties[:indexed]
         gem
       end
+
+      def fetch_gem_versions(gem)
+        results = db["
+          SELECT rubygem.name,
+                 version.number, version.platform
+          FROM rubygems rubygem
+          JOIN versions version
+            ON version.rubygem_id = rubygem.id
+          WHERE rubygem.name = ?
+            AND version.indexed = ?", gem.to_a, true].to_a
+        results.group_by {|r| r[:name] }.each do |gem, rows|
+          requirements = rows.group_by {|r| [r[:number], r[:platform]] }
+
+          value = requirements.map do |version, r|
+
+            {
+              :number => version.first,
+              :platform => version.last
+            }
+          end
+
+          yield(gem, value)
+      end
     end
   end
 end

lib/gemstash/gem_source/upstream_source.rb

@@ -62,6 +62,10 @@ def serve_versions
         redirect index_upstream.url("versions", request.query_string)
       end
 
+      def serve_gem_versions(name)
+        redirect index_upstream.url("api/v1/versions/#{name}", request.query_string)
+      end
+
       def serve_info(name)
         redirect index_upstream.url("info/#{name}", request.query_string)
       end

lib/gemstash/web.rb

@@ -45,6 +45,10 @@ def http_client_for(server_url)
       @gem_source.serve_dependencies_json
     end
 
+    get "/api/v1/versions/:name" do
+      @gem_source.serve_gem_versions(params[:name])
+    end
+
     post "/api/v1/gems" do
       @gem_source.serve_add_gem
     end