.htaccess_html5bp

# Apache Server Configs v2.11.0 | MIT License
# https://github.com/h5bp/server-configs-apache

# (!) Using `.htaccess` files slows down Apache, therefore, if you have
# access to the main server configuration file (which is usually called
# `httpd.conf`), you should add this logic there.
#
# https://httpd.apache.org/docs/current/howto/htaccess.html.

# ######################################################################
# # CROSS-ORIGIN                                                       #
# ######################################################################

# ----------------------------------------------------------------------
# | Cross-origin requests                                              |
# ----------------------------------------------------------------------

# Allow cross-origin requests.
#
# https://developer.mozilla.org/en-US/docs/Web/HTTP/Access_control_CORS
# http://enable-cors.org/
# http://www.w3.org/TR/cors/

# <IfModule mod_headers.c>
#     Header set Access-Control-Allow-Origin "*"
# </IfModule>

# ----------------------------------------------------------------------
# | Cross-origin images                                                |
# ----------------------------------------------------------------------

# Send the CORS header for images when browsers request it.
#
# https://developer.mozilla.org/en-US/docs/Web/HTML/CORS_enabled_image
# https://blog.chromium.org/2011/07/using-cross-domain-images-in-webgl-and.html

<IfModule mod_setenvif.c>
    <IfModule mod_headers.c>
        <FilesMatch "\.(bmp|cur|gif|ico|jpe?g|png|svgz?|webp)$">
            SetEnvIf Origin ":" IS_CORS
            Header set Access-Control-Allow-Origin "*" env=IS_CORS
        </FilesMatch>
    </IfModule>
</IfModule>

# ----------------------------------------------------------------------
# | Cross-origin web fonts                                             |
# ----------------------------------------------------------------------

# Allow cross-origin access to web fonts.

<IfModule mod_headers.c>
    <FilesMatch "\.(eot|otf|tt[cf]|woff2?)$">
        Header set Access-Control-Allow-Origin "*"
    </FilesMatch>
</IfModule>

# ----------------------------------------------------------------------
# | Cross-origin resource timing                                       |
# ----------------------------------------------------------------------

# Allow cross-origin access to the timing information for all resources.
#
# If a resource isn't served with a `Timing-Allow-Origin` header that
# would allow its timing information to be shared with the document,
# some of the attributes of the `PerformanceResourceTiming` object will
# be set to zero.
#
# http://www.w3.org/TR/resource-timing/
# http://www.stevesouders.com/blog/2014/08/21/resource-timing-practical-tips/

# <IfModule mod_headers.c>
#     Header set Timing-Allow-Origin: "*"
# </IfModule>


# ######################################################################
# # ERRORS                                                             #
# ######################################################################

# ----------------------------------------------------------------------
# | Custom error messages/pages                                        |
# ----------------------------------------------------------------------

# Customize what Apache returns to the client in case of an error.
# https://httpd.apache.org/docs/current/mod/core.html#errordocument

ErrorDocument 404 /404.html

# ----------------------------------------------------------------------
# | Error prevention                                                   |
# ----------------------------------------------------------------------

# Disable the pattern matching based on filenames.
#
# This setting prevents Apache from returning a 404 error as the result
# of a rewrite when the directory with the same name does not exist.
#
# https://httpd.apache.org/docs/current/content-negotiation.html#multiviews

Options -MultiViews


# ######################################################################
# # INTERNET EXPLORER                                                  #
# ######################################################################

# ----------------------------------------------------------------------
# | Document modes                                                     |
# ----------------------------------------------------------------------

# Force Internet Explorer 8/9/10 to render pages in the highest mode
# available in the various cases when it may not.
#
# https://hsivonen.fi/doctype/#ie8
#
# (!) Starting with Internet Explorer 11, document modes are deprecated.
# If your business still relies on older web apps and services that were
# designed for older versions of Internet Explorer, you might want to
# consider enabling `Enterprise Mode` throughout your company.
#
# http://msdn.microsoft.com/en-us/library/ie/bg182625.aspx#docmode
# http://blogs.msdn.com/b/ie/archive/2014/04/02/stay-up-to-date-with-enterprise-mode-for-internet-explorer-11.aspx

<IfModule mod_headers.c>
    Header set X-UA-Compatible "IE=edge"
    # `mod_headers` cannot match based on the content-type, however,
    # the `X-UA-Compatible` response header should be send only for
    # HTML documents and not for the other resources.
    <FilesMatch "\.(appcache|atom|bbaw|bmp|crx|css|cur|eot|f4[abpv]|flv|geojson|gif|htc|ico|jpe?g|js|json(ld)?|m4[av]|manifest|map|mp4|oex|og[agv]|opus|otf|pdf|png|rdf|rss|safariextz|svgz?|swf|topojson|tt[cf]|txt|vcard|vcf|vtt|webapp|web[mp]|woff2?|xloc|xml|xpi)$">
        Header unset X-UA-Compatible
    </FilesMatch>
</IfModule>

# ----------------------------------------------------------------------
# | Iframes cookies                                                    |
# ----------------------------------------------------------------------

# Allow cookies to be set from iframes in Internet Explorer.
#
# http://msdn.microsoft.com/en-us/library/ms537343.aspx
# http://www.w3.org/TR/2000/CR-P3P-20001215/

# <IfModule mod_headers.c>
#     Header set P3P "policyref=\"/w3c/p3p.xml\", CP=\"IDC DSP COR ADM DEVi TAIi PSA PSD IVAi IVDi CONi HIS OUR IND CNT\""
# </IfModule>


# ######################################################################
# # MEDIA TYPES AND CHARACTER ENCODINGS                                #
# ######################################################################

# ----------------------------------------------------------------------
# | Media types                                                        |
# ----------------------------------------------------------------------

# Serve resources with the proper media types (f.k.a. MIME types).
#
# https://www.iana.org/assignments/media-types/media-types.xhtml
# https://httpd.apache.org/docs/current/mod/mod_mime.html#addtype

<IfModule mod_mime.c>

  # Data interchange

    AddType application/json                            json map topojson
    AddType application/ld+json                         jsonld
    AddType application/vnd.geo+json                    geojson
    AddType application/xml                             atom rdf rss xml


  # JavaScript

    # Normalize to standard type.
    # https://tools.ietf.org/html/rfc4329#section-7.2

    AddType application/javascript                      js


  # Manifest files

    # If you are providing a web application manifest file (see
    # the specification: https://w3c.github.io/manifest/), it is
    # recommended that you serve it with the `application/manifest+json`
    # media type.
    #
    # Because the web application manifest file doesn't have its
    # own unique file extension, you can set its media type either
    # by matching:
    #
    # 1) the exact location of the file (this can be done using a
    #    directive such as `<Location>`, but it will NOT work in
    #    the `.htaccess` file, so you will have to do it in the main
    #    server configuration file or inside of a `<VirtualHost>`
    #    container)
    #
    #    e.g.:
    #
    #       <Location "/.well-known/manifest.json">
    #           AddType application/manifest+json               json
    #       </Location>
    #
    # 2) the filename (this can be problematic as you will need to
    #    ensure that you don't have any other file with the same name
    #    as the one you gave to your web application manifest file)
    #
    #    e.g.:
    #
    #       <Files "manifest.json">
    #           AddType application/manifest+json               json
    #       </Files>

    AddType application/x-web-app-manifest+json         webapp
    AddType text/cache-manifest                         appcache manifest


  # Media files

    AddType audio/mp4                                   f4a f4b m4a
    AddType audio/ogg                                   oga ogg opus
    AddType image/bmp                                   bmp
    AddType image/webp                                  webp
    AddType video/mp4                                   f4v f4p m4v mp4
    AddType video/ogg                                   ogv
    AddType video/webm                                  webm
    AddType video/x-flv                                 flv
    AddType image/svg+xml                               svg svgz

    # Serving `.ico` image files with a different media type
    # prevents Internet Explorer from displaying then as images:
    # https://github.com/h5bp/html5-boilerplate/commit/37b5fec090d00f38de64b591bcddcb205aadf8ee

    AddType image/x-icon                                cur ico


  # Web fonts

    AddType application/font-woff                       woff
    AddType application/font-woff2                      woff2
    AddType application/vnd.ms-fontobject               eot

    # Browsers usually ignore the font media types and simply sniff
    # the bytes to figure out the font type.
    # https://mimesniff.spec.whatwg.org/#matching-a-font-type-pattern
    #
    # However, Blink and WebKit based browsers will show a warning
    # in the console if the following font types are served with any
    # other media types.

    AddType application/x-font-ttf                      ttc ttf
    AddType font/opentype                               otf


  # Other

    AddType application/octet-stream                    safariextz
    AddType application/x-bb-appworld                   bbaw
    AddType application/x-chrome-extension              crx
    AddType application/x-opera-extension               oex
    AddType application/x-xpinstall                     xpi
    AddType text/vcard                                  vcard vcf
    AddType text/vnd.rim.location.xloc                  xloc
    AddType text/vtt                                    vtt
    AddType text/x-component                            htc

</IfModule>

# ----------------------------------------------------------------------
# | Character encodings                                                |
# ----------------------------------------------------------------------

# Serve all resources labeled as `text/html` or `text/plain`
# with the media type `charset` parameter set to `UTF-8`.
#
# https://httpd.apache.org/docs/current/mod/core.html#adddefaultcharset

AddDefaultCharset utf-8

# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

# Serve the following file types with the media type `charset`
# parameter set to `UTF-8`.
#
# https://httpd.apache.org/docs/current/mod/mod_mime.html#addcharset

<IfModule mod_mime.c>
    AddCharset utf-8 .atom \
                     .bbaw \
                     .css \
                     .geojson \
                     .js \
                     .json \
                     .jsonld \
                     .rdf \
                     .rss \
                     .topojson \
                     .vtt \
                     .webapp \
                     .xloc \
                     .xml
</IfModule>


# ######################################################################
# # REWRITES                                                           #
# ######################################################################

# ----------------------------------------------------------------------
# | Rewrite engine                                                     |
# ----------------------------------------------------------------------

# (1) Turn on the rewrite engine (this is necessary in order for
#     the `RewriteRule` directives to work).
#
#     https://httpd.apache.org/docs/current/mod/mod_rewrite.html#RewriteEngine
#
# (2) Enable the `FollowSymLinks` option if it isn't already.
#
#     https://httpd.apache.org/docs/current/mod/core.html#options
#
# (3) If your web host doesn't allow the `FollowSymlinks` option,
#     you need to comment it out or remove it, and then uncomment
#     the `Options +SymLinksIfOwnerMatch` line (4), but be aware
#     of the performance impact.
#
#     https://httpd.apache.org/docs/current/misc/perf-tuning.html#symlinks
#
# (4) Some cloud hosting services will require you set `RewriteBase`.
#
#     http://www.rackspace.com/knowledge_center/frequently-asked-question/why-is-modrewrite-not-working-on-my-site
#     https://httpd.apache.org/docs/current/mod/mod_rewrite.html#rewritebase
#
# (5) Depending on how your server is set up, you may also need to
#     use the `RewriteOptions` directive to enable some options for
#     the rewrite engine.
#
#     https://httpd.apache.org/docs/current/mod/mod_rewrite.html#rewriteoptions

<IfModule mod_rewrite.c>

    # (1)
    RewriteEngine On

    # (2)
    Options +FollowSymlinks

    # (3)
    # Options +SymLinksIfOwnerMatch

    # (4)
    # RewriteBase /

    # (5)
    # RewriteOptions <options>

</IfModule>

# ----------------------------------------------------------------------
# | Forcing `https://`                                                 |
# ----------------------------------------------------------------------

# Redirect from the `http://` to the `https://` version of the URL.
# https://wiki.apache.org/httpd/RewriteHTTPToHTTPS

# <IfModule mod_rewrite.c>
#    RewriteEngine On
#    RewriteCond %{HTTPS} !=on
#    RewriteRule ^(.*)$ https://%{HTTP_HOST}/$1 [R=301,L]
# </IfModule>

# ----------------------------------------------------------------------
# | Suppressing / Forcing the `www.` at the beginning of URLs          |
# ----------------------------------------------------------------------

# The same content should never be available under two different
# URLs, especially not with and without `www.` at the beginning.
# This can cause SEO problems (duplicate content), and therefore,
# you should choose one of the alternatives and redirect the other
# one.
#
# By default `Option 1` (no `www.`) is activated.
# http://no-www.org/faq.php?q=class_b
#
# If you would prefer to use `Option 2`, just comment out all the
# lines from `Option 1` and uncomment the ones from `Option 2`.
#
# (!) NEVER USE BOTH RULES AT THE SAME TIME!

# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

# Option 1: rewrite www.example.com → example.com

<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteCond %{HTTPS} !=on
    RewriteCond %{HTTP_HOST} ^www\.(.+)$ [NC]
    RewriteRule ^ http://%1%{REQUEST_URI} [R=301,L]
</IfModule>

# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

# Option 2: rewrite example.com → www.example.com
#
# Be aware that the following might not be a good idea if you use "real"
# subdomains for certain parts of your website.

# <IfModule mod_rewrite.c>
#     RewriteEngine On
#     RewriteCond %{HTTPS} !=on
#     RewriteCond %{HTTP_HOST} !^www\. [NC]
#     RewriteCond %{SERVER_ADDR} !=127.0.0.1
#     RewriteCond %{SERVER_ADDR} !=::1
#     RewriteRule ^ http://www.%{HTTP_HOST}%{REQUEST_URI} [R=301,L]
# </IfModule>


# ######################################################################
# # SECURITY                                                           #
# ######################################################################

# ----------------------------------------------------------------------
# | Clickjacking                                                       |
# ----------------------------------------------------------------------

# Protect website against clickjacking.
#
# The example below sends the `X-Frame-Options` response header with
# the value `DENY`, informing browsers not to display the content of
# the web page in any frame.
#
# This might not be the best setting for everyone. You should read
# about the other two possible values the `X-Frame-Options` header
# field can have: `SAMEORIGIN` and `ALLOW-FROM`.
# https://tools.ietf.org/html/rfc7034#section-2.1.
#
# Keep in mind that while you could send the `X-Frame-Options` header
# for all of your website’s pages, this has the potential downside that
# it forbids even non-malicious framing of your content (e.g.: when
# users visit your website using a Google Image Search results page).
#
# Nonetheless, you should ensure that you send the `X-Frame-Options`
# header for all pages that allow a user to make a state changing
# operation (e.g: pages that contain one-click purchase links, checkout
# or bank-transfer confirmation pages, pages that make permanent
# configuration changes, etc.).
#
# Sending the `X-Frame-Options` header can also protect your website
# against more than just clickjacking attacks:
# https://cure53.de/xfo-clickjacking.pdf.
#
# https://tools.ietf.org/html/rfc7034
# http://blogs.msdn.com/b/ieinternals/archive/2010/03/30/combating-clickjacking-with-x-frame-options.aspx
# https://www.owasp.org/index.php/Clickjacking

# <IfModule mod_headers.c>
#     Header set X-Frame-Options "DENY"
#     # `mod_headers` cannot match based on the content-type, however,
#     # the `X-Frame-Options` response header should be send only for
#     # HTML documents and not for the other resources.
#     <FilesMatch "\.(appcache|atom|bbaw|bmp|crx|css|cur|eot|f4[abpv]|flv|geojson|gif|htc|ico|jpe?g|js|json(ld)?|m4[av]|manifest|map|mp4|oex|og[agv]|opus|otf|pdf|png|rdf|rss|safariextz|svgz?|swf|topojson|tt[cf]|txt|vcard|vcf|vtt|webapp|web[mp]|woff2?|xloc|xml|xpi)$">
#         Header unset X-Frame-Options
#     </FilesMatch>
# </IfModule>

# ----------------------------------------------------------------------
# | Content Security Policy (CSP)                                      |
# ----------------------------------------------------------------------

# Mitigate the risk of cross-site scripting and other content-injection
# attacks.
#
# This can be done by setting a `Content Security Policy` which
# whitelists trusted sources of content for your website.
#
# The example header below allows ONLY scripts that are loaded from the
# current website's origin (no inline scripts, no CDN, etc). That almost
# certainly won't work as-is for your website!
#
# For more details on how to craft a reasonable policy for your website,
# read: http://www.html5rocks.com/en/tutorials/security/content-security-policy/
# (or the specification: http://www.w3.org/TR/CSP11/). Also, to make
# things easier, you can use an online CSP header generator such as:
# http://cspisawesome.com/.

# <IfModule mod_headers.c>
#     Header set Content-Security-Policy "script-src 'self'; object-src 'self'"
#     # `mod_headers` cannot match based on the content-type, however,
#     # the `Content-Security-Policy` response header should be send
#     # only for HTML documents and not for the other resources.
#     <FilesMatch "\.(appcache|atom|bbaw|bmp|crx|css|cur|eot|f4[abpv]|flv|geojson|gif|htc|ico|jpe?g|js|json(ld)?|m4[av]|manifest|map|mp4|oex|og[agv]|opus|otf|pdf|png|rdf|rss|safariextz|svgz?|swf|topojson|tt[cf]|txt|vcard|vcf|vtt|webapp|web[mp]|woff2?|xloc|xml|xpi)$">
#         Header unset Content-Security-Policy
#     </FilesMatch>
# </IfModule>

# ----------------------------------------------------------------------
# | File access                                                        |
# ----------------------------------------------------------------------

# Block access to directories without a default document.
#
# You should leave the following uncommented, as you shouldn't allow
# anyone to surf through every directory on your server (which may
# includes rather private places such as the CMS's directories).

<IfModule mod_autoindex.c>
    Options -Indexes
</IfModule>

# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

# Block access to all hidden files and directories with the exception of
# the visible content from within the `/.well-known/` hidden directory.
#
# These types of files usually contain user preferences or the preserved
# state of an utility, and can include rather private places like, for
# example, the `.git` or `.svn` directories.
#
# The `/.well-known/` directory represents the standard (RFC 5785) path
# prefix for "well-known locations" (e.g.: `/.well-known/manifest.json`,
# `/.well-known/keybase.txt`), and therefore, access to its visible
# content should not be blocked.
#
# https://www.mnot.net/blog/2010/04/07/well-known
# https://tools.ietf.org/html/rfc5785

<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteCond %{REQUEST_URI} "!(^|/)\.well-known/([^./]+./?)+$" [NC]
    RewriteCond %{SCRIPT_FILENAME} -d [OR]
    RewriteCond %{SCRIPT_FILENAME} -f
    RewriteRule "(^|/)\." - [F]
</IfModule>

# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

# Block access to files that can expose sensitive information.
#
# By default, block access to backup and source files that may be
# left by some text editors and can pose a security risk when anyone
# has access to them.
#
# http://feross.org/cmsploit/
#
# (!) Update the `<FilesMatch>` regular expression from below to
# include any files that might end up on your production server and
# can expose sensitive information about your website. These files may
# include: configuration files, files that contain metadata about the
# project (e.g.: project dependencies), build scripts, etc..

<FilesMatch "(^#.*#|\.(bak|conf|dist|fla|in[ci]|log|psd|sh|sql|sw[op])|~)$">

    # Apache < 2.3
    <IfModule !mod_authz_core.c>
        Order allow,deny
        Deny from all
        Satisfy All
    </IfModule>

    # Apache ≥ 2.3
    <IfModule mod_authz_core.c>
        Require all denied
    </IfModule>

</FilesMatch>

# ----------------------------------------------------------------------
# | HTTP Strict Transport Security (HSTS)                              |
# ----------------------------------------------------------------------

# Force client-side SSL redirection.
#
# If a user types `example.com` in their browser, even if the server
# redirects them to the secure version of the website, that still leaves
# a window of opportunity (the initial HTTP connection) for an attacker
# to downgrade or redirect the request.
#
# The following header ensures that browser will ONLY connect to your
# server via HTTPS, regardless of what the users type in the browser's
# address bar.
#
# (!) Remove the `includeSubDomains` optional directive if the website's
# subdomains are not using HTTPS.
#
# http://www.html5rocks.com/en/tutorials/security/transport-layer-security/
# https://tools.ietf.org/html/draft-ietf-websec-strict-transport-sec-14#section-6.1
# http://blogs.msdn.com/b/ieinternals/archive/2014/08/18/hsts-strict-transport-security-attacks-mitigations-deployment-https.aspx

# <IfModule mod_headers.c>
#     Header set Strict-Transport-Security "max-age=16070400; includeSubDomains"
# </IfModule>

# ----------------------------------------------------------------------
# | Reducing MIME type security risks                                  |
# ----------------------------------------------------------------------

# Prevent some browsers from MIME-sniffing the response.
#
# This reduces exposure to drive-by download attacks and cross-origin
# data leaks, and should be left uncommented, especially if the server
# is serving user-uploaded content or content that could potentially be
# treated as executable by the browser.
#
# http://www.slideshare.net/hasegawayosuke/owasp-hasegawa
# http://blogs.msdn.com/b/ie/archive/2008/07/02/ie8-security-part-v-comprehensive-protection.aspx
# http://msdn.microsoft.com/en-us/library/ie/gg622941.aspx
# https://mimesniff.spec.whatwg.org/

<IfModule mod_headers.c>
    Header set X-Content-Type-Options "nosniff"
</IfModule>

# ----------------------------------------------------------------------
# | Reflected Cross-Site Scripting (XSS) attacks                       |
# ----------------------------------------------------------------------

# (1) Try to re-enable the cross-site scripting (XSS) filter built
#     into most web browsers.
#
#     The filter is usually enabled by default, but in some cases it
#     may be disabled by the user. However, in Internet Explorer for
#     example, it can be re-enabled just by sending the
#     `X-XSS-Protection` header with the value of `1`.
#
# (2) Prevent web browsers from rendering the web page if a potential
#     reflected (a.k.a non-persistent) XSS attack is detected by the
#     filter.
#
#     By default, if the filter is enabled and browsers detect a
#     reflected XSS attack, they will attempt to block the attack
#     by making the smallest possible modifications to the returned
#     web page.
#
#     Unfortunately, in some browsers (e.g.: Internet Explorer),
#     this default behavior may allow the XSS filter to be exploited,
#     thereby, it's better to inform browsers to prevent the rendering
#     of the page altogether, instead of attempting to modify it.
#
#     http://hackademix.net/2009/11/21/ies-xss-filter-creates-xss-vulnerabilities
#
# (!) Do not rely on the XSS filter to prevent XSS attacks! Ensure that
#     you are taking all possible measures to prevent XSS attacks, the
#     most obvious being: validating and sanitizing your website's inputs.
#
# http://blogs.msdn.com/b/ie/archive/2008/07/02/ie8-security-part-iv-the-xss-filter.aspx
# http://blogs.msdn.com/b/ieinternals/archive/2011/01/31/controlling-the-internet-explorer-xss-filter-with-the-x-xss-protection-http-header.aspx
# https://www.owasp.org/index.php/Cross-site_Scripting_%28XSS%29

# <IfModule mod_headers.c>
#     #                           (1)    (2)
#     Header set X-XSS-Protection "1; mode=block"
#     # `mod_headers` cannot match based on the content-type, however,
#     # the `X-XSS-Protection` response header should be send only for
#     # HTML documents and not for the other resources.
#     <FilesMatch "\.(appcache|atom|bbaw|bmp|crx|css|cur|eot|f4[abpv]|flv|geojson|gif|htc|ico|jpe?g|js|json(ld)?|m4[av]|manifest|map|mp4|oex|og[agv]|opus|otf|pdf|png|rdf|rss|safariextz|svgz?|swf|topojson|tt[cf]|txt|vcard|vcf|vtt|webapp|web[mp]|woff2?|xloc|xml|xpi)$">
#         Header unset X-XSS-Protection
#     </FilesMatch>
# </IfModule>

# ----------------------------------------------------------------------
# | Server software information                                        |
# ----------------------------------------------------------------------

# Prevent Apache from sending in the `Server` response header its
# exact version number, the description of the generic OS-type or
# information about its compiled-in modules.
#
# (!) The `ServerTokens` directive will only work in the main server
# configuration file, so don't try to enable it in the `.htaccess` file!
#
# https://httpd.apache.org/docs/current/mod/core.html#servertokens

# ServerTokens Prod


# ######################################################################
# # WEB PERFORMANCE                                                    #
# ######################################################################

# ----------------------------------------------------------------------
# | Compression                                                        |
# ----------------------------------------------------------------------

<IfModule mod_deflate.c>

    # Force compression for mangled `Accept-Encoding` request headers
    # https://developer.yahoo.com/blogs/ydn/pushing-beyond-gzipping-25601.html

    <IfModule mod_setenvif.c>
        <IfModule mod_headers.c>
            SetEnvIfNoCase ^(Accept-EncodXng|X-cept-Encoding|X{15}|~{15}|-{15})$ ^((gzip|deflate)\s*,?\s*)+|[X~-]{4,13}$ HAVE_Accept-Encoding
            RequestHeader append Accept-Encoding "gzip,deflate" env=HAVE_Accept-Encoding
        </IfModule>
    </IfModule>

    # - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

    # Compress all output labeled with one of the following media types.
    #
    # (!) For Apache versions below version 2.3.7 you don't need to
    # enable `mod_filter` and can remove the `<IfModule mod_filter.c>`
    # and `</IfModule>` lines as `AddOutputFilterByType` is still in
    # the core directives.
    #
    # https://httpd.apache.org/docs/current/mod/mod_filter.html#addoutputfilterbytype

    <IfModule mod_filter.c>
        AddOutputFilterByType DEFLATE "application/atom+xml" \
                                      "application/javascript" \
                                      "application/json" \
                                      "application/ld+json" \
                                      "application/manifest+json" \
                                      "application/rdf+xml" \
                                      "application/rss+xml" \
                                      "application/schema+json" \
                                      "application/vnd.geo+json" \
                                      "application/vnd.ms-fontobject" \
                                      "application/x-font-ttf" \
                                      "application/x-javascript" \
                                      "application/x-web-app-manifest+json" \
                                      "application/xhtml+xml" \
                                      "application/xml" \
                                      "font/eot" \
                                      "font/opentype" \
                                      "image/bmp" \
                                      "image/svg+xml" \
                                      "image/vnd.microsoft.icon" \
                                      "image/x-icon" \
                                      "text/cache-manifest" \
                                      "text/css" \
                                      "text/html" \
                                      "text/javascript" \
                                      "text/plain" \
                                      "text/vcard" \
                                      "text/vnd.rim.location.xloc" \
                                      "text/vtt" \
                                      "text/x-component" \
                                      "text/x-cross-domain-policy" \
                                      "text/xml"

    </IfModule>

    # - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

    # Map the following filename extensions to the specified
    # encoding type in order to make Apache serve the file types
    # with the appropriate `Content-Encoding` response header
    # (do note that this will NOT make Apache compress them!).
    #
    # If these files types would be served without an appropriate
    # `Content-Enable` response header, client applications (e.g.:
    # browsers) wouldn't know that they first need to uncompress
    # the response, and thus, wouldn't be able to understand the
    # content.
    #
    # https://httpd.apache.org/docs/current/mod/mod_mime.html#addencoding

    <IfModule mod_mime.c>
        AddEncoding gzip              svgz
    </IfModule>

</IfModule>

# ----------------------------------------------------------------------
# | Content transformation                                             |
# ----------------------------------------------------------------------

# Prevent intermediate caches or proxies (e.g.: such as the ones
# used by mobile network providers) from modifying the website's
# content.
#
# https://tools.ietf.org/html/rfc2616#section-14.9.5
#
# (!) If you are using `mod_pagespeed`, please note that setting
# the `Cache-Control: no-transform` response header will prevent
# `PageSpeed` from rewriting `HTML` files, and, if the
# `ModPagespeedDisableRewriteOnNoTransform` directive isn't set
# to `off`, also from rewriting other resources.
#
# https://developers.google.com/speed/pagespeed/module/configuration#notransform

# <IfModule mod_headers.c>
#     Header merge Cache-Control "no-transform"
# </IfModule>

# ----------------------------------------------------------------------
# | ETags                                                              |
# ----------------------------------------------------------------------

# Remove `ETags` as resources are sent with far-future expires headers.
#
# https://developer.yahoo.com/performance/rules.html#etags
# https://tools.ietf.org/html/rfc7232#section-2.3

# `FileETag None` doesn't work in all cases.
<IfModule mod_headers.c>
    Header unset ETag
</IfModule>

FileETag None

# ----------------------------------------------------------------------
# | Expires headers                                                    |
# ----------------------------------------------------------------------

# Serve resources with far-future expires headers.
#
# (!) If you don't control versioning with filename-based
# cache busting, you should consider lowering the cache times
# to something like one week.
#
# https://httpd.apache.org/docs/current/mod/mod_expires.html

<IfModule mod_expires.c>

    ExpiresActive on
    ExpiresDefault                                      "access plus 1 month"

  # CSS
    ExpiresByType text/css                              "access plus 1 year"

  # Data interchange
    ExpiresByType application/atom+xml                  "access plus 1 hour"
    ExpiresByType application/rdf+xml                   "access plus 1 hour"
    ExpiresByType application/rss+xml                   "access plus 1 hour"

    ExpiresByType application/json                      "access plus 0 seconds"
    ExpiresByType application/ld+json                   "access plus 0 seconds"
    ExpiresByType application/schema+json               "access plus 0 seconds"
    ExpiresByType application/vnd.geo+json              "access plus 0 seconds"
    ExpiresByType application/xml                       "access plus 0 seconds"
    ExpiresByType text/xml                              "access plus 0 seconds"

  # Favicon (cannot be renamed!) and cursor images
    ExpiresByType image/vnd.microsoft.icon              "access plus 1 week"
    ExpiresByType image/x-icon                          "access plus 1 week"

  # HTML
    ExpiresByType text/html                             "access plus 0 seconds"

  # JavaScript
    ExpiresByType application/javascript                "access plus 1 year"
    ExpiresByType application/x-javascript              "access plus 1 year"
    ExpiresByType text/javascript                       "access plus 1 year"

  # Manifest files
    ExpiresByType application/manifest+json             "access plus 1 year"

    ExpiresByType application/x-web-app-manifest+json   "access plus 0 seconds"
    ExpiresByType text/cache-manifest                   "access plus 0 seconds"

  # Media files
    ExpiresByType audio/ogg                             "access plus 1 month"
    ExpiresByType image/bmp                             "access plus 1 month"
    ExpiresByType image/gif                             "access plus 1 month"
    ExpiresByType image/jpeg                            "access plus 1 month"
    ExpiresByType image/png                             "access plus 1 month"
    ExpiresByType image/svg+xml                         "access plus 1 month"
    ExpiresByType video/mp4                             "access plus 1 month"
    ExpiresByType video/ogg                             "access plus 1 month"
    ExpiresByType video/webm                            "access plus 1 month"

  # Web fonts

    # Embedded OpenType (EOT)
    ExpiresByType application/vnd.ms-fontobject         "access plus 1 month"
    ExpiresByType font/eot                              "access plus 1 month"

    # OpenType
    ExpiresByType font/opentype                         "access plus 1 month"

    # TrueType
    ExpiresByType application/x-font-ttf                "access plus 1 month"

    # Web Open Font Format (WOFF) 1.0
    ExpiresByType application/font-woff                 "access plus 1 month"
    ExpiresByType application/x-font-woff               "access plus 1 month"
    ExpiresByType font/woff                             "access plus 1 month"

    # Web Open Font Format (WOFF) 2.0
    ExpiresByType application/font-woff2                "access plus 1 month"

  # Other
    ExpiresByType text/x-cross-domain-policy            "access plus 1 week"

</IfModule>

# ----------------------------------------------------------------------
# | File concatenation                                                 |
# ----------------------------------------------------------------------

# Allow concatenation from within specific files.
#
# e.g.:
#
#   If you have the following lines in a file called, for
#   example, `main.combined.js`:
#
#       <!--#include file="js/jquery.js" -->
#       <!--#include file="js/jquery.timer.js" -->
#
#   Apache will replace those lines with the content of the
#   specified files.

# <IfModule mod_include.c>
#     <FilesMatch "\.combined\.js$">
#         Options +Includes
#         AddOutputFilterByType INCLUDES application/javascript \
#                                        application/x-javascript \
#                                        text/javascript
#         SetOutputFilter INCLUDES
#     </FilesMatch>
#     <FilesMatch "\.combined\.css$">
#         Options +Includes
#         AddOutputFilterByType INCLUDES text/css
#         SetOutputFilter INCLUDES
#     </FilesMatch>
# </IfModule>

# ----------------------------------------------------------------------
# | Filename-based cache busting                                       |
# ----------------------------------------------------------------------

# If you're not using a build process to manage your filename version
# revving, you might want to consider enabling the following directives
# to route all requests such as `/style.12345.css` to `/style.css`.
#
# To understand why this is important and even a better solution than
# using something like `*.css?v231`, please see:
# http://www.stevesouders.com/blog/2008/08/23/revving-filenames-dont-use-querystring/

# <IfModule mod_rewrite.c>
#     RewriteEngine On
#     RewriteCond %{REQUEST_FILENAME} !-f
#     RewriteRule ^(.+)\.(\d+)\.(bmp|css|cur|gif|ico|jpe?g|js|png|svgz?|webp)$ $1.$3 [L]
# </IfModule>