Re: [PATCH 11/18] gitweb: add isDumbClient() check
From: Jakub Narebski <hidden>
Date: 2016-06-15 22:50:13
"John 'Warthog9' Hawley" [off-list ref] writes:
quoted hunk ↗ jump to hunk
Basic check for the claimed Agent string, if it matches a known blacklist (wget and curl currently) don't display the 'Generating...' page. Jakub has mentioned a couple of other possible ways to handle this, so if a better way comes along this should be used as a wrapper to any better way we can find to deal with this. Signed-off-by: John 'Warthog9' Hawley <warthog9@eaglescrag.net> --- gitweb/lib/cache.pl | 30 ++++++++++++++++++++++++++++++ 1 files changed, 30 insertions(+), 0 deletions(-)diff --git a/gitweb/lib/cache.pl b/gitweb/lib/cache.pl index d55b572..5182a94 100644 --- a/gitweb/lib/cache.pl +++ b/gitweb/lib/cache.pl@@ -116,6 +116,34 @@ sub isFeedAction { return 0; # False } +# There have been a number of requests that things like "dumb" clients, I.E. wget +# lynx, links, etc (things that just download, but don't parse the html) actually +# work without getting the wonkiness that is the "Generating..." page. +# +# There's only one good way to deal with this, and that's to read the browser User +# Agent string and do matching based on that. This has a whole slew of error cases +# and mess, but there's no other way to determine if the "Generating..." page +# will break things. +# +# This assumes the client is not dumb, thus the default behavior is to return +# "false" (0) (and eventually the "Generating..." page). If it is a dumb client +# return "true" (1) +sub isDumbClient {
Please don't use mixedCase, but underline_separated words, e.g. browser_is_robot(), or client_is_dumb().
+ my($user_agent) = $ENV{'HTTP_USER_AGENT'};
What if $ENV{'HTTP_USER_AGENT'} is unset / undef, e.g. because we are
runing gitweb as a script... which includes running gitweb tests?
+
+ if(
+ # wget case
+ $user_agent =~ /^Wget/i
+ ||
+ # curl should be excluded I think, probably better safe than sorry
+ $user_agent =~ /^curl/i
+ ){
+ return 1; # True
+ }
+
+ return 0;
+}
Compare (note: handcrafted solution is to whitelist, not blacklist):
+sub browser_is_robot {
+ return 1 if !exists $ENV{'HTTP_USER_AGENT'}; # gitweb run as script
+ if (eval { require HTTP::BrowserDetect; }) {
+ my $browser = HTTP::BrowserDetect->new();
+ return $browser->robot();
+ }
+ # fallback on detecting known web browsers
+ return 0 if ($ENV{'HTTP_USER_AGENT'} =~ /\b(?:Mozilla|Opera|Safari|IE)\b/);
+ # be conservative; if not sure, assume non-interactive
+ return 1;
+}
from
"[PATCHv6 17/24] gitweb: Show appropriate "Generating..." page when regenerating cache"
http://thread.gmane.org/gmane.comp.version-control.git/163052/focus=163040
http://repo.or.cz/w/git/jnareb-git.git/commitdiff/48679f7985ccda16dc54fda97790841bab4a0ba2
--
Jakub Narebski
Poland
ShadeHawk on #git