write CaaS cat as a temporary file

this will make it eaiser to set the content-type correctly

app.rb

@@ -499,19 +499,28 @@ get "/bytes/:size" do
 end
 
 get "/kitty" do
-  caas_host = ENV.fetch "CAAS_SERVICE_HOST"
-  caas_port = ENV.fetch "CAAS_SERVICE_PORT"
+  caas_host = ENV.fetch "CAAS_SERVICE_HOST", nil
+  caas_port = ENV.fetch "CAAS_SERVICE_PORT", nil
   url = "http://#{caas_host}:#{caas_port}/"
-  response = HTTParty.head(url)
-  content_type response.headers["content-type"]
-  stream do |out|
+  unless caas_host && caas_port
+    # fail-safe url
+    url = "https://i.imgur.com/epzPw7L.jpeg"
+  end
+  path = Tempfile.open binmode: true do |f|
+    # f.chmod 0o644
     response = HTTParty.get(url, stream_body: true) do |fragment|
       if [301, 302].include? fragment.code
+        print "skip writing for redirect"
       elsif fragment.code == 200
-        out << fragment
+        f.write fragment
       else
         raise StandardError, "non-success status code while streaming #{fragment.code}"
       end
     end
+
+    content_type response.headers["content-type"]
+    f.path
   end
+  send_file path
+  File.delete path
 end