Adding compression support can be very simple -- if your spider is coded in Perl using LWP::UserAgent, then the
addition of a single line of code will enable compression support.
$ua->default_header('Accept-Encoding' => 'gzip');
and then you need to make sure that you always refer to 'decoded_content' when dealing with the response object.
For other languages, all
you need to do is to add
Accept-encoding: gzipto the HTTP request that you send, and then be prepared to deal with a 'content-encoding: gzip' in the response.
Happily, some of the large spiders do support compression -- the googlebot and Yahoo Slurp do (to name but two). Since I started prodding crawler implementors, a couple have implemented compression (one within hours), and another reported that it was a bug that it didn't work -- which would be fixed shortly.
Crawlers which do more than 5% of the total (uncompressed) crawling activity are marked in bold below.
| Crawler | Last IP used |
|---|---|
| CowBot/0.4" "gladstonefamily.net | 90.92.88.131 |
| CowBot/0.4" "pond1.gladstonefamily.net | 90.92.88.131 |
| ia_archiver" "pond1.gladstonefamily.net | 54.173.35.129 |
| masscan/1.0 (https://github.com/robertdavidgraham/masscan)" "- | 67.219.125.132 |
| Mozilla/5.0 (compatible; archive.org_bot +http://archive.org/details/archive.org_bot)" "pond1.gladstonefamily.net | 207.241.231.163 |
| Mozilla/5.0 (compatible; DotBot/1.1; http://www.opensiteexplorer.org/dotbot, help@moz.com)" "blog1.gladstonefamily.net | 216.244.66.194 |
| Mozilla/5.0 (compatible; DotBot/1.1; http://www.opensiteexplorer.org/dotbot, help@moz.com)" "charon.gladstonefamily.net | 216.244.66.194 |
| Mozilla/5.0 (compatible; DotBot/1.1; http://www.opensiteexplorer.org/dotbot, help@moz.com)" "gladstone.name | 216.244.66.228 |
| Mozilla/5.0 (compatible; DotBot/1.1; http://www.opensiteexplorer.org/dotbot, help@moz.com)" "pond.gladstonefamily.net | 216.244.66.194 |
| Mozilla/5.0 (compatible; DotBot/1.1; http://www.opensiteexplorer.org/dotbot, help@moz.com)" "pond1.gladstonefamily.net | 216.244.66.194 |
| Mozilla/5.0 (compatible; DotBot/1.1; http://www.opensiteexplorer.org/dotbot, help@moz.com)" "www.gladstone.name | 216.244.66.228 |
| Mozilla/5.0 (compatible; ips-agent)" "www.gladstonefamily.net | 69.58.178.56 |
| Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:50.0) Gecko/20100101 Firefox/50.0" "gladstonefamily.net | 198.46.177.93 |
| Python-urllib/2.7 | 118.219.252.177 |