example.vcl

# A simplified version of the Lullabot best-practices Varnish configuration as
# described at:
#
# http://www.lullabot.com/articles/varnish-multiple-web-servers-drupal
#
# This configuration only uses a single web server on the localhost, optimized
# for a single machine instead of multiple web servers.
#

vcl 4.0;

# Define the internal network subnet.
# These are used below to allow internal access to certain files while not
# allowing access from the public internet.
acl internal {
  "127.0.0.0"/24;
}

backend default {
  .host = "127.0.0.1";
  .port = "8080";
}

# Respond to incoming requests.
sub vcl_recv {

  if (req.http.x-forwarded-for) {
    set req.http.X-Forwarded-For = req.http.X-Forwarded-For + ", " + client.ip;
  } else {
    set req.http.X-Forwarded-For = client.ip;
  }

  # Do not cache these paths.
  if (req.url ~ "^/status\.php$" ||
      req.url ~ "^/update\.php$" ||
      req.url ~ "^/admin/build/features" ||
      req.url ~ "^/check_locale.*$" ||
      req.url ~ "^/info/.*$" ||
      req.url ~ "^/flag/.*$" ||
      req.url ~ "^.*/ajax/.*$" ||
      req.url ~ "^.*/ahah/.*$") {
       return (pass);
  }

  # Pipe these paths directly to Apache for streaming.
  if (req.url ~ "^/admin/content/backup_migrate/export") {
    return (pipe);
  }

  # Do not allow outside access to cron.php, install.php, or php files in /info.
  if (req.url ~ "^/(cron|install|/info/.*)\.php$" && !client.ip ~ internal) {
    # Have Varnish throw the error directly.
    return (synth(404, "Page not found."));
    # Use a custom error page that you've defined in Drupal at the path "404".
    # set req.url = "/404";
  }

  # Handle compression correctly. Different browsers send different
  # "Accept-Encoding" headers, even though they mostly all support the same
  # compression mechanisms. By consolidating these compression headers into
  # a consistent format, we can reduce the size of the cache and get more hits.=
  # @see: http:// varnish.projects.linpro.no/wiki/FAQ/Compression
  if (req.http.Accept-Encoding) {
    if (req.http.Accept-Encoding ~ "gzip") {
      # If the browser supports it, we'll use gzip.
      set req.http.Accept-Encoding = "gzip";
    }
    else if (req.http.Accept-Encoding ~ "deflate") {
      # Next, try deflate if it is supported.
      set req.http.Accept-Encoding = "deflate";
    }
    else {
      # Unknown algorithm. Remove it and send unencoded.
      unset req.http.Accept-Encoding;
    }
  }

  # Always cache the following file types for all users.
  if (req.url ~ "(?i)\.(png|gif|jpeg|jpg|ico|swf|css|js)(\?[a-z0-9]+)?$") {
    unset req.http.Cookie;
  }

  # Remove all cookies that Drupal doesn't need to know about. ANY remaining
  # cookie will cause the request to pass-through to Apache. For the most part
  # we always set the NO_CACHE cookie after any POST request, disabling the
  # Varnish cache temporarily. The session cookie allows all authenticated users
  # to pass through as long as they're logged in.
  if (req.http.Cookie) {
    set req.http.Cookie = ";" + req.http.Cookie;
    set req.http.Cookie = regsuball(req.http.Cookie, "; +", ";");
    set req.http.Cookie = regsuball(req.http.Cookie, ";(SESS[a-z0-9]+|NO_CACHE)=", "; \1=");
    set req.http.Cookie = regsuball(req.http.Cookie, ";[^ ][^;]*", "");
    set req.http.Cookie = regsuball(req.http.Cookie, "^[; ]+|[; ]+$", "");

    if (req.http.Cookie == "") {
      # If there are no remaining cookies, remove the cookie header. If there
      # aren't any cookie headers, Varnish's default behavior will be to cache
      # the page.
      unset req.http.Cookie;
    }
    else {
      # If there is any cookies left (a session or NO_CACHE cookie), do not
      # cache the page. Pass it on to Apache directly.
      return (pass);
    }
  }
}

# Routine used to determine the cache key if storing/retrieving a cached page.
sub vcl_hash {
  # Include cookie in cache hash.
  # This check is unnecessary because we already pass on all cookies.
  # if (req.http.Cookie) {
  #   set req.hash += req.http.Cookie;
  # }
}

# Code determining what to do when serving items from the Apache servers.
sub vcl_backend_response {
  # Don't allow static files to set cookies.
  if (bereq.url ~ "(?i)\.(png|gif|jpeg|jpg|ico|swf|css|js)(\?[a-z0-9]+)?$") {
    # beresp == Back-end response from the web server.
    unset beresp.http.set-cookie;
  }

  # Cache 404 errors for 10 seconds.
  if (beresp.status == 404) {
    set beresp.ttl = 10s;
  }

  # Keep stale copies for a long, long time so they can be used on infrequent pages.
  set beresp.grace = 30d;
}

# In the event of an error, show friendlier messages.
sub vcl_synth {
  # Redirect to some other URL in the case of a homepage failure.
  #if (req.url ~ "^/?$") {
  #  set resp.status = 302;
  #  set resp.http.Location = "http://backup.example.com/";
  #}

  # Otherwise redirect to the homepage, which will likely be in the cache.
  set resp.http.Content-Type = "text/html; charset=utf-8";
  synthetic ({"
  <html>
  <head>
    <title>Page Unavailable</title>
    <style>
      body {
        background: #F1F2F6;
        font-family: Helvetica, Arial, sans-serif;
        font-size: 20px;
        text-align: center;
        color: #36323A;
      }
      #page {
        border: 1px solid #F1F2F6;
        -moz-box-shadow: 0 2px 4px rgba(46,47,51,0.5);
        -webkit-box-shadow: 0 2px 4px rgba(46,47,51,0.5);
        box-shadow: 0 2px 4px rgba(46,47,51,0.5);
        width: 600px;
        margin: 100px auto 0;
        background: #FFF;
      }
      #page-inner {
        padding: 30px;
      }
      .site-name {
        background-color: #2A3142;
        color: #fff;
        padding: 15px 30px;
      }
      .site-name span {
        color: #20F0B3;
      }
      a, a:link, a:visited { color: #CCC; }
      .error { color: #222; }
    </style>
  </head>
  <body>
    <div id="page">
      <div class="site-name"><span>Online</span> MBA REPORT</div>
      <div id="page-inner">
        <h1 class="title">Page Unavailable</h1>
        <p>The page you requested is temporarily unavailable.</p>
        <div class="error">(Error "} + resp.status + " " + resp.reason + {")</div>
      </div>
    </div>
  </body>
  </html>
"});
  return (deliver);
}