Improve access log handler to handle HEAD method.

[ksauzz]

This fix prevents to include BytesOut element on Head Object(KeyStat) request the same as Head Bucket(BucketStat).

Requires the latest erlcloud commit: https://github.com/basho/erlcloud/pull/12/commits
Fix #789

[kuenishi]

 BytesOut = case Method of
                  'HEAD' -> 0;
                  _ ->      Length
            end,

I prefer this style.

[kuenishi]

Would you mind tagging erlcloud as 0.4.3 point to it from rebar.confg ?

Then I'll give my small +1.

make test and make pulse was confirmed eventually.

[shino]

Sorry for stepping in, but I have a question/not-so-clear-point-for-me.

I don't what #wm_log_data.response_length represents, the name suggests
it's a length of response body, not Content-Length header value.
Does someone have information on this point?

If my above understanding is correct, #wm_log_data.response_length should be set
by Webmachine to zero for every HEAD request.

Quick fix by Webmachine side is:

diff --git a/src/webmachine_request.erl b/src/webmachine_request.erl
index 2a5ff7a..cc25d0c 100644
--- a/src/webmachine_request.erl
+++ b/src/webmachine_request.erl
@@ -389,7 +389,7 @@ send_response(Code, PassedState=#wm_reqstate{reqdata=RD}, _Req) ->
           make_code(Code), <<"\r\n">> |
          make_headers(Code, Length, RD)]),
     FinalLength = case wrq:method(RD) of
-         'HEAD' -> Length;
+         'HEAD' -> 0;
          _ ->
             case Body of
                 {stream, Body2} ->

With this fix,

• Content-Length of response for HEAD request is correct, same as GET,
• Access stats for KeyStat has only Count, no BytesOut.

[shino]

Oh, the above quick fix has a side effect to access log [1].

BEFORE fix:

127.0.0.1 - - [06/Feb/2014:00:34:14 +0900] "HEAD /buckets/test5/objects/A.txt HTTP/1.1" 200 2 "" "curl/7.27.0"
                                                                                            ^

AFTER fix:

127.0.0.1 - - [06/Feb/2014:00:47:54 +0900] "HEAD /buckets/test5/objects/A.txt HTTP/1.1" 200 0 "" "curl/7.27.0"
                                                                                            ^

The number of "The response size in bytes" differs.
Zero is good for HEAD or not?

[1] Logging · basho/webmachine Wiki > https://github.com/basho/webmachine/wiki/Logging

[kuenishi]

Looks like a wm bug. Fixing webmachine won't conflict with this fix and r_t added here , which is very useful. I also prefer faster 1.4.5 roll out for customers. Let's fix webmachine eventually. Maybe it's busy but not too busy. Thoughts?

[shino]

Bug is fixed by this PR. +1 for defering WM fix.
@ksauzz Would you file a issue about access log?

[ksauzz]

@kota I'll bump the version of erlcloud to 0.4.4 since the latest version is 0.4.3.
@shino OK. I'll do that later.

[kota]

@ksauzz @shino you guys mentioning a wrong person again.

[shino]

@kota I'm very sorry for bothering again (and again)... Internal ID to mention @kuenishi is @kota so my fingers type the spell ....

[ksauzz]

@kota So sorry. Please accept my apologies....

[kota]

@shino @ksauzz No problem. :)

[ksauzz]

Updated the code style and bumped erlcloud version.