Request for compressed response in AndroidWebRequest

[asmirnov]

Background

In order to save traffic and loading time we can request for 'gzip'ped stream from the server.
Related issue #4916

What to change

Change AndroidWebRequest class to request/return compressed stream from the server.

[asmirnov]

As reported in Google blog (​https://android-developers.googleblog.com/2011/09/androids-http-clients.html) gzip compression is requested by default and handled automatically:

In Gingerbread, we added transparent response compression. HttpURLConnection will automatically add this header to outgoing requests, and handle the corresponding response:

Accept-Encoding: gzip

Take advantage of this by configuring your Web server to compress responses for clients that can support it. If response compression is problematic, the class documentation shows how to disable it.

but i've seen some feedbacks that it's not done automatically for ​http:// requests. To be checked.

[asmirnov]

i've tested with gzipping and the response content length for ​https://easylist-downloads.adblockplus.org/easylist.txt?addonName=adblockplusandroid&addonVersion=1.0.1.2&application=android&applicationVersion=24&platform=libadblockplus&platformVersion=1.0&lastVersion=0&downloadCount=0 is only 545584 bytes (gzip) instead of 2297583 (identity)

[asmirnov]

gzip

[asmirnov]

identity

[abpbot]

A commit referencing this issue has landed:
​Issue 4977 - Request for compressed response in AndroidWebRequest