Unity Dash Online Video Search in Ubuntu 12.10

I was learning how to use ngrep, a command line tool that let you search and filter all the network traffic coming in and out from our machine. While testing to see what being transfer from and to port 80 ( see command below), I notice my newly upgraded Ubuntu 12.10 keep on making HTTP request to videosearch.ubuntu.com.
$ sudo apt-get install ngrep
$ sudo ngrep -d any port 80

It seems, default settings in Ubuntu 12.10 enables unity video lens to periodically connect to this server to search information for video recommendation. It is advisable to remove or disable this unused and unnecessary feature. Just type this command and logout and re-login your session.
$ sudo apt-get --purge remove unity-scope-video-remote

I was curious of the content in the JSON file. So we going to make a manual HTTP query to capture the file. Note that direct browser query will return empty result (suspect user agent checking) so we have to use curl or wget.
$ curl -o videosearch.json http://videosearch.ubuntu.com/v0/search?q=&sources=Amazon

The returned JSON file contains a list of YouTube videos. Changes to the request parameters(q and sources) returns almost similar result. Nothing interesting here. Let's inspect the HTTP response header instead.
$ curl -D header videosearch.json http://videosearch.ubuntu.com/v0/search?q=&sources=Amazon

Note that I removed the timestamp and added some comments
$ cat header
HTTP/1.1 200 OK
Date: .....
Server: gevent/0.13.0 gunicorn/0.13.4

The response is coming from gunicorn, a lightweight Python WSGI HTTP server using gevent, a coroutine Python networking library.
Vary: X-Geo-Country

What HTTP request header fields (in this case X-Geo-Country) to be used in caching decision either to regenerate from application server or reload from proxy server.
Content-Type: application/json
Content-Length: 10309
Expires: ......

Age: 203

The age in seconds of the JSON file in the proxy cache.
X-Cache: HIT from alkes.canonical.com
X-Cache-Lookup: HIT from alkes.canonical.com:3128

Requested content is found in the cache (HIT) of the caching server.
Via: 1.0 alkes.canonical.com:3128 (squid/2.7.STABLE7)

Squid, popular web caching server.
Via: 1.1 videosearch.ubuntu.com
Connection: close

The HTTP request has gone (back and forth) through these two servers. Note that alkes.canonical.com is Ubuntu music search API server.