.htaccess

# Apache Server Configs v3.2.1 | 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
# https://enable-cors.org/
# https://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.
#
# https://developers.google.com/fonts/docs/troubleshooting

<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.
#
# https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Timing-Allow-Origin
# https://www.w3.org/TR/resource-timing/
# https://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.
#
# https://msdn.microsoft.com/en-us/library/ie/bg182625.aspx#docmode
# https://blogs.msdn.microsoft.com/ie/2014/04/02/stay-up-to-date-with-enterprise-mode-for-internet-explorer-11/
# https://msdn.microsoft.com/en-us/library/ff955275.aspx

<IfModule mod_headers.c>
    Header set X-UA-Compatible "IE=edge" "expr=%{CONTENT_TYPE} =~ m#text/html#i"
</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/atom+xml                        atom
    AddType application/json                            json map topojson
    AddType application/ld+json                         jsonld
    AddType application/rss+xml                         rss
    AddType application/geo+json                        geojson
    AddType application/rdf+xml                         rdf
    AddType application/xml                             xml


  # JavaScript

    # Servers should use text/javascript for JavaScript resources.
    # https://html.spec.whatwg.org/multipage/scripting.html#scriptingLanguages

    AddType text/javascript                             js mjs


  # Manifest files

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


  # Media files

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

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

    AddType image/x-icon                                cur ico


  # WebAssembly

    AddType application/wasm                            wasm


  # Web fonts

    AddType font/woff                                   woff
    AddType font/woff2                                  woff2
    AddType application/vnd.ms-fontobject               eot
    AddType font/ttf                                    ttf
    AddType font/collection                             ttc
    AddType font/otf                                    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/calendar                               ics
    AddType text/markdown                               markdown md
    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 .appcache \
                     .bbaw \
                     .css \
                     .htc \
                     .ics \
                     .js \
                     .json \
                     .manifest \
                     .map \
                     .markdown \
                     .md \
                     .mjs \
                     .topojson \
                     .vtt \
                     .vcard \
                     .vcf \
                     .webmanifest \
                     .xloc
</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`.
#
#     https://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
#
# (6) Set %{ENV:PROTO} variable, to allow rewrites to redirect with the
#     appropriate schema automatically (http or https).

<IfModule mod_rewrite.c>

    # (1)
    RewriteEngine On

    # (2)
    Options +FollowSymlinks

    # (3)
    # Options +SymLinksIfOwnerMatch

    # (4)
    # RewriteBase /

    # (5)
    # RewriteOptions <options>

    # (6)
    RewriteCond %{HTTPS} =on
    RewriteRule ^ - [env=proto:https]
    RewriteCond %{HTTPS} !=on
    RewriteRule ^ - [env=proto:http]

</IfModule>

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

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

# (1) If you're using cPanel AutoSSL or the Let's Encrypt webroot
#     method it will fail to validate the certificate if validation
#     requests are redirected to HTTPS. Turn on the condition(s)
#     you need.
#
#     https://www.iana.org/assignments/well-known-uris/well-known-uris.xhtml
#     https://tools.ietf.org/html/draft-ietf-acme-acme-12

# <IfModule mod_rewrite.c>
#    RewriteEngine On
#    RewriteCond %{HTTPS} !=on
#    # (1)
#    # RewriteCond %{REQUEST_URI} !^/\.well-known/acme-challenge/
#    # RewriteCond %{REQUEST_URI} !^/\.well-known/cpanel-dcv/[\w-]+$
#    # RewriteCond %{REQUEST_URI} !^/\.well-known/pki-validation/[A-F0-9]{32}\.txt(?:\ Comodo\ DCV)?$
#    RewriteRule ^ https://%{HTTP_HOST}%{REQUEST_URI} [R=301,L]
# </IfModule>

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

# Rewrite www.example.com → example.com

# 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.
#
# (!) NEVER USE BOTH WWW-RELATED RULES AT THE SAME TIME!

# (1) The rule assumes by default that both HTTP and HTTPS
#     environments are available for redirection.
#     If your SSL certificate could not handle one of the domains
#     used during redirection, you should turn the condition on.
#
#     https://github.com/h5bp/server-configs-apache/issues/52

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

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

# Rewrite example.com → www.example.com

# 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.
#
# (!) NEVER USE BOTH WWW-RELATED RULES AT THE SAME TIME!

# (1) The rule assumes by default that both HTTP and HTTPS
#     environments are available for redirection.
#     If your SSL certificate could not handle one of the domains
#     used during redirection, you should turn the condition on.
#
#     https://github.com/h5bp/server-configs-apache/issues/52

# 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
#     # (1)
#     # RewriteCond %{HTTPS} !=on
#     RewriteCond %{HTTP_HOST} !^www\. [NC]
#     RewriteCond %{SERVER_ADDR} !=127.0.0.1
#     RewriteCond %{SERVER_ADDR} !=::1
#     RewriteRule ^ %{ENV:PROTO}://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://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Frame-Options
# https://tools.ietf.org/html/rfc7034
# https://blogs.msdn.microsoft.com/ieinternals/2010/03/30/combating-clickjacking-with-x-frame-options/
# https://www.owasp.org/index.php/Clickjacking

# <IfModule mod_headers.c>
#     Header set X-Frame-Options "DENY" "expr=%{CONTENT_TYPE} =~ m#text/html#i"
# </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.
#
# There is no policy that fits all websites, you will have to modify
# the `Content-Security-Policy` directives in the example below depending
# on your needs.
#
# The example policy below aims to:
#
#  (1) Restrict all fetches by default to the origin of the current website
#      by setting the `default-src` directive to `'self'` - which acts as a
#      fallback to all "Fetch directives" (https://developer.mozilla.org/en-US/docs/Glossary/Fetch_directive).
#
#      This is convenient as you do not have to specify all Fetch directives
#      that apply to your site, for example:
#      `connect-src 'self'; font-src 'self'; script-src 'self'; style-src 'self'`, etc.
#
#      This restriction also means that you must explicitly define from
#      which site(s) your website is allowed to load resources from.
#
#  (2) The `<base>` element is not allowed on the website. This is to
#      prevent attackers from changing the locations of resources loaded
#      from relative URLs.
#
#      If you want to use the `<base>` element, then `base-uri 'self'`
#      can be used instead.
#
#  (3) Form submissions are only allowed from the current website by
#      setting: `form-action 'self'`.
#
#  (4) Prevents all websites (including your own) from embedding your
#      webpages within e.g. the `<iframe>` or `<object>` element by
#      setting `frame-ancestors 'none'`.
#
#	   The `frame-ancestors` directive helps avoid "Clickjacking" attacks
#      and is similar to the `X-Frame-Options` header.
#
#      Browsers that support the CSP header will ignore `X-Frame-Options`
#      if `frame-ancestors` is also specified.
#
#  (5) Forces the browser to treat all the resources that are served over
#      HTTP as if they were loaded securely over HTTPS by setting the
#      `upgrade-insecure-requests` directive.
#
#      Please note that `upgrade-insecure-requests` does not ensure
#      HTTPS for the top-level navigation. If you want to force the
#      website itself to be loaded over HTTPS you must include the
#      `Strict-Transport-Security` header.
#
# To make your CSP implementation easier, you can use an online CSP header
# generator such as:
# https://report-uri.com/home/generate/
#
# It is encouraged that you validate your CSP header using a CSP validator
# such as:
# https://csp-evaluator.withgoogle.com
#
# https://csp.withgoogle.com/docs/
# https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy
# https://www.html5rocks.com/en/tutorials/security/content-security-policy/
# https://www.w3.org/TR/CSP/

# <IfModule mod_headers.c>
#     #                                   (1)                 (2)              (3)                 (4)                     (5)
#     Header set Content-Security-Policy "default-src 'self'; base-uri 'none'; form-action 'self'; frame-ancestors 'none'; upgrade-insecure-requests" "expr=%{CONTENT_TYPE} =~ m#text/html#i"
# </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.
#
# https://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..

<IfModule mod_authz_core.c>
    <FilesMatch "(^#.*#|\.(bak|conf|dist|fla|in[ci]|log|orig|psd|sh|sql|sw[op])|~)$">
        Require all denied
    </FilesMatch>
</IfModule>

# ----------------------------------------------------------------------
# | 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.
#
# (!) Be aware that this, once published, is not revokable and you must ensure
# being able to serve the site via SSL for the duration you've specified
# in max-age. When you don't have a valid SSL connection (anymore) your
# visitors will see a nasty error message even when attempting to connect
# via simple HTTP.
#
# (!) Remove the `includeSubDomains` optional directive if the website's
# subdomains are not using HTTPS.
#
# (1) If you want to submit your site for HSTS preload (2) you must
#     * ensure the `includeSubDomains` directive to be present
#     * the `preload` directive to be specified
#     * the `max-age` to be at least 31536000 seconds (1 year) according to the current status.
#
#     It is also advised (3) to only serve the HSTS header via a secure connection
#     which can be done with either `env=https` or `"expr=%{HTTPS} == 'on'"` (4). The
#     exact way depends on your environment and might just be tried.
#
# (2) https://hstspreload.org/
# (3) https://tools.ietf.org/html/rfc6797#section-7.2
# (4) https://stackoverflow.com/questions/24144552/how-to-set-hsts-header-from-htaccess-only-on-https/24145033#comment81632711_24145033
#
# https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Strict-Transport-Security
# https://tools.ietf.org/html/rfc6797#section-6.1
# https://www.html5rocks.com/en/tutorials/security/transport-layer-security/
# https://blogs.msdn.microsoft.com/ieinternals/2014/08/18/strict-transport-security/

# <IfModule mod_headers.c>
#     Header always set Strict-Transport-Security "max-age=16070400; includeSubDomains"
#     # (1) or if HSTS preloading is desired (respect (2) for current requirements):
#     # Header always set Strict-Transport-Security "max-age=31536000; includeSubDomains; preload" env=HTTPS
#     # (4) respectively… (respect (2) for current requirements):
#     # Header always set Strict-Transport-Security "max-age=31536000; includeSubDomains; preload" "expr=%{HTTPS} == 'on'"
# </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.
#
# https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Content-Type-Options
# https://blogs.msdn.microsoft.com/ie/2008/07/02/ie8-security-part-v-comprehensive-protection/
# 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.
#
#     https://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.
#
# https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-XSS-Protection
# https://blogs.msdn.microsoft.com/ie/2008/07/02/ie8-security-part-iv-the-xss-filter/
# https://blogs.msdn.microsoft.com/ieinternals/2011/01/31/controlling-the-xss-filter/
# 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" "expr=%{CONTENT_TYPE} =~ m#text/html#i"
# </IfModule>

# ----------------------------------------------------------------------
# | Referrer Policy                                                    |
# ----------------------------------------------------------------------

# A web application uses HTTPS and a URL-based session identifier.
# The web application might wish to link to HTTPS resources on other
# web sites without leaking the user's session identifier in the URL.
#
# This can be done by setting a `Referrer Policy` which
# whitelists trusted sources of content for your website.
#
# To check your referrer policy, you can use an online service
# such as: https://securityheaders.io/.
#
# https://scotthelme.co.uk/a-new-security-header-referrer-policy/
# https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Referrer-Policy

# <IfModule mod_headers.c>
#     # no-referrer-when-downgrade (default)
#     # This should be the user agent's default behavior if no policy is
#     # specified.The origin is sent as referrer to a-priori as-much-secure
#     # destination (HTTPS->HTTPS), but isn't sent to a less secure destination
#     # (HTTPS->HTTP).
#     Header set Referrer-Policy "no-referrer-when-downgrade" "expr=%{CONTENT_TYPE} =~ m#text/html#i"
# </IfModule>

# ----------------------------------------------------------------------
# | Disable TRACE HTTP Method                                          |
# ----------------------------------------------------------------------

# Prevent Apache from responding to `TRACE` HTTP request.
#
# The TRACE method, while apparently harmless, can be successfully
# leveraged in some scenarios to steal legitimate users' credentials
#
# Modern browsers now prevent TRACE requests being made via JavaScript,
# however, other ways of sending TRACE requests with browsers have been
# discovered, such as using Java.
#
# (!) The `TraceEnable` directive will only work in the main server
# configuration file, so don't try to enable it in the `.htaccess` file!
#
# https://tools.ietf.org/html/rfc7231#section-4.3.8
# https://www.owasp.org/index.php/Cross_Site_Tracing
# https://www.owasp.org/index.php/Test_HTTP_Methods_(OTG-CONFIG-006)
# https://httpd.apache.org/docs/current/mod/core.html#traceenable

# TraceEnable Off

# ----------------------------------------------------------------------
# | Server-side technology information                                 |
# ----------------------------------------------------------------------

# Remove the `X-Powered-By` response header that:
#
#  * is set by some frameworks and server-side languages
#    (e.g.: ASP.NET, PHP), and its value contains information
#    about them (e.g.: their name, version number)
#
#  * doesn't provide any value to users, contributes to header
#    bloat, and in some cases, the information it provides can
#    expose vulnerabilities
#
# (!) If you can, you should disable the `X-Powered-By` header from the
# language / framework level (e.g.: for PHP, you can do that by setting
# `expose_php = off` in `php.ini`)
#
# https://php.net/manual/en/ini.core.php#ini.expose-php

<IfModule mod_headers.c>
    Header unset X-Powered-By
    Header always unset X-Powered-By
</IfModule>

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

# Prevent Apache from adding a trailing footer line containing
# information about the server to the server-generated documents
# (e.g.: error messages, directory listings, etc.)
#
# https://httpd.apache.org/docs/current/mod/core.html#serversignature

ServerSignature Off

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

# 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.mozilla.org/en-US/docs/Web/HTTP/Headers/Accept-Encoding
    # https://calendar.perfplanet.com/2010/pushing-beyond-gzipping/

    <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.
    #
    # 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/geo+json" \
                                      "application/vnd.ms-fontobject" \
                                      "application/wasm" \
                                      "application/x-font-ttf" \
                                      "application/x-javascript" \
                                      "application/x-web-app-manifest+json" \
                                      "application/xhtml+xml" \
                                      "application/xml" \
                                      "font/eot" \
                                      "font/opentype" \
                                      "font/otf" \
                                      "image/bmp" \
                                      "image/svg+xml" \
                                      "image/vnd.microsoft.icon" \
                                      "text/cache-manifest" \
                                      "text/calendar" \
                                      "text/css" \
                                      "text/html" \
                                      "text/javascript" \
                                      "text/plain" \
                                      "text/markdown" \
                                      "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://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Encoding
    # https://httpd.apache.org/docs/current/mod/mod_mime.html#addencoding

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

</IfModule>

# ----------------------------------------------------------------------
# | Brotli pre-compressed content                                      |
# ----------------------------------------------------------------------

# Serve brotli compressed CSS, JS, HTML, SVG, ICS and JSON files
# if they exist and if the client accepts br encoding.
#
# (!) To make this part relevant, you need to generate encoded
# files by your own. Enabling this part will not auto-generate
# brotlied files.
#
# Note that some clients (eg. browsers) require a secure connection
# to request brotli-compressed resources.
# https://www.chromestatus.com/feature/5420797577396224
#
# https://httpd.apache.org/docs/current/mod/mod_brotli.html#precompressed

# <IfModule mod_headers.c>

#     RewriteCond %{HTTP:Accept-Encoding} br
#     RewriteCond %{REQUEST_FILENAME}\.br -f
#     RewriteRule \.(css|ics|js|json|html|svg)$ %{REQUEST_URI}.br [L]

#     # Prevent mod_deflate double gzip
#     RewriteRule \.br$ - [E=no-gzip:1]

#     <FilesMatch "\.br$">

#         <IfModule mod_mime.c>
#             # Serve correct content types
#             AddType text/css              css.br
#             AddType text/calendar         ics.br
#             AddType text/javascript       js.br
#             AddType application/json      json.br
#             AddType text/html             html.br
#             AddType image/svg+xml         svg.br

#             # Serve correct content charset
#             AddCharset utf-8 .css.br \
#                              .ics.br \
#                              .js.br \
#                              .json.br
#         </IfModule>

#         # Force proxies to cache brotlied and non-brotlied files separately
#         Header append Vary Accept-Encoding

#     </FilesMatch>

#     # Serve correct encoding type
#     AddEncoding br .br

# </IfModule>

# ----------------------------------------------------------------------
# | GZip pre-compressed content                                        |
# ----------------------------------------------------------------------

# Serve gzip compressed CSS, JS, HTML, SVG, ICS and JSON files
# if they exist and if the client accepts gzip encoding.
#
# (!) To make this part relevant, you need to generate encoded
# files by your own. Enabling this part will not auto-generate
# gziped files.
#
# https://httpd.apache.org/docs/current/mod/mod_deflate.html#precompressed
#
# (1)
# Removing default MIME Type for .gz files allowing to add custom
# sub-types.
# You may prefer using less generic extensions such as .html_gz in
# order to keep default behavior regarding .gz files.
# https://httpd.apache.org/docs/current/mod/mod_mime.html#removetype

# <IfModule mod_headers.c>

#     RewriteCond %{HTTP:Accept-Encoding} gzip
#     RewriteCond %{REQUEST_FILENAME}\.gz -f
#     RewriteRule \.(css|ics|js|json|html|svg)$ %{REQUEST_URI}.gz [L]

#     # Prevent mod_deflate double gzip
#     RewriteRule \.gz$ - [E=no-gzip:1]

#     <FilesMatch "\.gz$">

#         # Serve correct content types
#         <IfModule mod_mime.c>
#             # (1)
#             RemoveType gz

#             # Serve correct content types
#             AddType text/css              css.gz
#             AddType text/calendar         ics.gz
#             AddType text/javascript       js.gz
#             AddType application/json      json.gz
#             AddType text/html             html.gz
#             AddType image/svg+xml         svg.gz

#             # Serve correct content charset
#             AddCharset utf-8 .css.gz \
#                              .ics.gz \
#                              .js.gz \
#                              .json.gz
#         </IfModule>

#         # Force proxies to cache gzipped and non-gzipped files separately
#         Header append Vary Accept-Encoding

#     </FilesMatch>

#     # Serve correct encoding type
#     AddEncoding gzip .gz

# </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://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cache-Control
# 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.mozilla.org/en-US/docs/Web/HTTP/Headers/ETag
# 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

# ----------------------------------------------------------------------
# | Cache expiration                                                   |
# ----------------------------------------------------------------------

# Serve resources with far-future expiration date.
#
# (!) If you don't control versioning with filename-based
# cache busting, you should consider lowering the cache times
# to something like one week.
#
# https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cache-Control
# https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Expires
# 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/geo+json                  "access plus 0 seconds"
    ExpiresByType application/xml                       "access plus 0 seconds"
    ExpiresByType text/calendar                         "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 week"
    ExpiresByType application/x-web-app-manifest+json   "access plus 0 seconds"
    ExpiresByType text/cache-manifest                   "access plus 0 seconds"


  # Markdown

    ExpiresByType text/markdown                         "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 image/webp                            "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"


  # WebAssembly

    ExpiresByType application/wasm                      "access plus 1 year"


  # Web fonts

    # Collection
    ExpiresByType font/collection                       "access plus 1 month"

    # 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"
    ExpiresByType font/otf                              "access plus 1 month"

    # TrueType
    ExpiresByType application/x-font-ttf                "access plus 1 month"
    ExpiresByType 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"
    ExpiresByType 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:
# https://www.stevesouders.com/blog/2008/08/23/revving-filenames-dont-use-querystring/

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