jkbk

Well, duh, that’s exactly what I said, when you take the original post about an extra line break in account; note “note the weird line break” ??
I proposed the workaround to avoid messing with the plugin’s source file, as they will be overwritten when updated.

I managed to stumble over the solution!

This bug is essentially a duplicate of this, which is caused in lib/W3/Environment/WpLoader.php in line 26/27, which in some cases (like a separated wp/wp-content setup) generates wp-content/plugins/w3tc-wp-loader.php. Here’s the offending part, note the weird line break:

$file_data = "
<?php
    if (W3TC_WP_LOADING)

If used together with gzip, it’s not just headers/warnings (as in the linked post above), it really corrupts the compressed asset files.

Until this is fixed, here’s a workaround, which i found through a different issue (with a smilar setup – capistrano / “own wordpress directory”):

1. add define('DONOTVERIFY_WP_LOADER', true); to wp-config.php – this prevents the automatic creation of w3tc-wp-loader.php
2. create/modify w3tc-wp-loader.php and point it to wp-load.php

Mine looks like this:

<?php
    if (W3TC_WP_LOADING)
        require_once dirname(__FILE__).'/../../wp/wp-load.php';

Make sure there’s no newlines or whitespace before the opening php tag ??

I just checked the minified, gzipped file in the disk cache (wp-content/cache/minify/000000/01234/default.include.012345.css.gzip), and it is OK, as expected. I guess minification is triggered on request, this is where the extra newline gets tossed in; as soon as the file is served from disk, it’s gone.

Well, one server actually does have GZIP enabled (though there is no switch in the configuration tool); the other (a vanilla XAMPP) doesn’t. I checked both the conf files and did some curl’ing.
Here’s what phpinfo() says:


Apache Version Apache/2.4.18 (Unix) OpenSSL/1.0.2g PHP/5.6.20 mod_perl/2.0.8-dev Perl/v5.16.3

Loaded Modules core mod_so http_core prefork mod_authn_file mod_authn_dbm mod_authn_anon mod_authn_dbd mod_authn_socache mod_authn_core mod_authz_host mod_authz_groupfile mod_authz_user mod_authz_dbm mod_authz_owner mod_authz_dbd mod_authz_core mod_authnz_ldap mod_access_compat mod_auth_basic mod_auth_form mod_auth_digest mod_allowmethods mod_file_cache mod_socache_shmcb mod_socache_dbm mod_socache_memcache mod_dbd mod_bucketeer mod_dumpio mod_echo mod_case_filter mod_case_filter_in mod_buffer mod_ratelimit mod_reqtimeout mod_ext_filter mod_request mod_include mod_filter mod_substitute mod_sed mod_charset_lite mod_mime util_ldap mod_log_config mod_log_debug mod_logio mod_env mod_mime_magic mod_cern_meta mod_expires mod_headers mod_usertrack mod_unique_id mod_setenvif mod_version mod_remoteip mod_proxy mod_proxy_connect mod_proxy_ftp mod_proxy_http mod_proxy_fcgi mod_proxy_scgi mod_proxy_ajp mod_proxy_balancer mod_proxy_express mod_session mod_session_cookie mod_session_dbd mod_slotmem_shm mod_ssl mod_lbmethod_byrequests mod_lbmethod_bytraffic mod_lbmethod_bybusyness mod_lbmethod_heartbeat mod_unixd mod_dav mod_status mod_autoindex mod_info mod_suexec mod_cgi mod_cgid mod_dav_fs mod_vhost_alias mod_negotiation mod_dir mod_actions mod_speling mod_userdir mod_alias mod_rewrite mod_php5 mod_perl

Here’s the response headers of a corrupt file (GZIP enabled via W3TC):


HTTP/1.1 200 OK
Date: Tue, 12 Jul 2016 07:10:48 GMT
Server: Apache/2.4.18 (Unix) OpenSSL/1.0.2g PHP/5.6.20 mod_perl/2.0.8-dev Perl/v5.16.3
Vary: Accept-Encoding
X-Powered-By: PHP/5.6.20
Pragma: private
Last-Modified: Thu, 07 Jul 2016 13:25:58 GMT
Content-Length: 37162
Content-Encoding: gzip
Keep-Alive: timeout=5, max=99
Connection: Keep-Alive
Content-Type: text/css; charset=utf-8


And here’s the response of the following request


HTTP/1.1 200 OK
Date: Tue, 12 Jul 2016 07:12:32 GMT
Server: Apache/2.4.18 (Unix) OpenSSL/1.0.2g PHP/5.6.20 mod_perl/2.0.8-dev Perl/v5.16.3
Vary: Accept-Encoding
Last-Modified: Tue, 12 Jul 2016 07:10:49 GMT
ETag: "912a-5376af7eb3040"
Accept-Ranges: bytes
Content-Length: 37162
Keep-Alive: timeout=5, max=99
Connection: Keep-Alive
Content-Type: text/css
Content-Encoding: gzip


Note: I have not enabled eTags, that’s Apache’s doing, which I can’t turn off for some reason.

This is the same file, with W3TC’s GZIP disabled:


Accept-Ranges:bytes
Connection:Keep-Alive
Content-Length:243454
Content-Type:text/css
Date:Tue, 12 Jul 2016 07:35:25 GMT
ETag:"3b6fe-5376b12ae6280"
Keep-Alive:timeout=5, max=99
Last-Modified:Tue, 12 Jul 2016 07:18:18 GMT
Server:Apache/2.4.18 (Unix) OpenSSL/1.0.2g PHP/5.6.20 mod_perl/2.0.8-dev Perl/v5.16.3


hey ash, thanks for the quick response.
it’s not any one-click installer. iirc, i downloaded WP 4.5.2 and it updated itself once.
here’s the .htaccess:


# BEGIN W3TC Browser Cache
<IfModule mod_deflate.c>
<IfModule mod_headers.c>
Header append Vary User-Agent env=!dont-vary
</IfModule>
<IfModule mod_filter.c>
AddOutputFilterByType DEFLATE text/html text/richtext image/svg+xml text/plain text/xsd text/xsl text/xml image/x-icon application/json
<IfModule mod_mime.c>
# DEFLATE by extension
AddOutputFilter DEFLATE js css htm html xml
</IfModule>
</IfModule>
</IfModule>
# END W3TC Browser Cache
# BEGIN W3TC Page Cache core
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteCond %{HTTP:Accept-Encoding} gzip
RewriteRule .* - [E=W3TC_ENC:_gzip]
RewriteCond %{HTTP_COOKIE} w3tc_preview [NC]
RewriteRule .* - [E=W3TC_PREVIEW:_preview]
RewriteCond %{REQUEST_METHOD} !=POST
RewriteCond %{QUERY_STRING} =""
RewriteCond %{REQUEST_URI} \/$
RewriteCond %{HTTP_COOKIE} !(comment_author|wp\-postpass|w3tc_logged_out|wordpress_logged_in|wptouch_switch_toggle) [NC]
RewriteCond "%{DOCUMENT_ROOT}/wp-content/cache/page_enhanced/%{HTTP_HOST}/%{REQUEST_URI}/_index%{ENV:W3TC_PREVIEW}.html%{ENV:W3TC_ENC}" -f
RewriteRule .* "/wp-content/cache/page_enhanced/%{HTTP_HOST}/%{REQUEST_URI}/_index%{ENV:W3TC_PREVIEW}.html%{ENV:W3TC_ENC}" [L]
</IfModule>
# END W3TC Page Cache core
# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

# END WordPress