gistfile1.txt

You'll want to replace 'localwiki.org' with your hostname here.
----------------------
Add to localsettings.py:

OLWIDGET_CUSTOM_LAYER_TYPES = {
    'cachedcloudmade': """OpenLayers.Layer.CachedCloudMade('CachedCloudMade',
            ['//map-a.localwiki.org/tile/ca694687020d468283a545db191bcb81/35165/256/',
             '//map-b.localwiki.org/tile/ca694687020d468283a545db191bcb81/35165/256/',
             '//map-c.localwiki.org/tile/ca694687020d468283a545db191bcb81/35165/256/'])""",
}

--------------

Add to templates/olwidget/multi_layer_map.html:

diff --git a/sapling/templates/olwidget/multi_layer_map.html b/sapling/templates/olwidget/multi_layer_map.html
index 5631fc6..aa3746c 100644
--- a/sapling/templates/olwidget/multi_layer_map.html
+++ b/sapling/templates/olwidget/multi_layer_map.html
@@ -3,6 +3,15 @@
 <div id="{{ id }}"></div>
 {{ layer_html|join:"" }}
 
+{% comment %}
+  We need to explicitly include this JS file because we're using a custom
+  base layer *and* we are using a custom class we defined, CachedCloudMade.
+
+  We can remove this line once we switch to a real TMS/XYZ server -- which
+  will probably happen when we create our own custom tiles from OSM data.
+{% endcomment %}
+<script type="text/javascript" src="{% static "olwidget/js/sapling_cloudmade.js" %}"></script>
+
 <script type="text/javascript">
     SaplingMap.init_openlayers();
     OpenLayers.ImgPath = '{% static "img/openlayers/themes/dark/" %}';

--------------------

Then we have an apache host set up for 'map.localwiki.org'.  The apache config proxies request to a varnish instance.  We have to proxy because varnish doesn't do SSL.  If you don't use ssl you can just point to varnish directly and have it listen on a public port.  If your site is running with SSL, though, you'll want the tiles to be SSL or you may see a warning:


<VirtualHost *:443>
        SSLEngine on
        SSLCertificateFile /etc/apache2/ssl/localwiki.org/localwiki.org.crt
        SSLCertificateKeyFile /etc/apache2/ssl/localwiki.org/localwiki.org.key
        SSLCACertificateFile /etc/apache2/ssl/localwiki.org/intermediate.crt
        Header set Strict-Transport-Security "max-age=1800"

        ServerName map.localwiki.org
        ServerAlias map-a.localwiki.org map.localwiki.org
        ServerAlias map-b.localwiki.org map.localwiki.org
        ServerAlias map-c.localwiki.org map.localwiki.org

        DocumentRoot /var/www/
        <Directory />
                Options FollowSymLinks
                AllowOverride None
        </Directory>
        <Directory /var/www/>
                Options -Indexes FollowSymLinks MultiViews
                AllowOverride None
                Order allow,deny
                allow from all
        </Directory>

        ErrorLog /var/log/apache2/error.log

        # Possible values include: debug, info, notice, warn, error, crit,
        # alert, emerg.
        LogLevel warn

        CustomLog /var/log/apache2/access.log combined

        <Proxy *>
            Order deny,allow
            Allow from all
        </Proxy>
        ProxyRequests off

        #####################################
        # Route /tile/ to cloudmade cache.
        #####################################
        # :6081 is our varnish instance that's caching cloudmade tiles
        <Location "/tile/">
            SetEnv proxy-nokeepalive 1
            SetEnv force-proxy-request-1.0

            ProxyPass http://127.0.0.1:6081/
            ProxyPassReverse http://127.0.0.1:6081/
        </Location>

</VirtualHost>


-----------------

And here's our /etc/varnish/default.vcl:

# This is a basic VCL configuration file for varnish.  See the vcl(7)
# man page for details on VCL syntax and semantics.
#
# Default backend definition.  Set this to point to your content
# server.
#
 backend default {
     #.host = "b.tile.cloudmade.com";
     .host = "205.251.203.16";
     .port = "80";
 }
#
# Below is a commented-out copy of the default VCL logic.  If you
# redefine any of these subroutines, the built-in logic will be
# appended to your code.
#
 sub vcl_recv {
     # Hardcode Host header to point to cloudmade tile server.
     set req.http.host = "b.tile.cloudmade.com";

     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;
     }
     if (req.request != "GET" &&
       req.request != "HEAD" &&
       req.request != "PUT" &&
       req.request != "POST" &&
       req.request != "TRACE" &&
       req.request != "OPTIONS" &&
       req.request != "DELETE") {
         /* Non-RFC2616 or CONNECT which is weird. */
         return (pipe);
     }
     if (req.request != "GET" && req.request != "HEAD") {
         /* We only deal with GET and HEAD by default */
         return (pass);
     }
     return (lookup);
 }
#
     if (!beresp.cacheable) {
         return (pass);
     }

     /* Remove Expires from backend, it's not long enough */
     unset beresp.http.expires;

     /* Set the clients TTL on this object */
     set beresp.http.cache-control = "max-age=900";

     /* Set how long Varnish will keep it */
     set beresp.ttl = 20w;

     /* marker for vcl_deliver to reset Age: */
     set beresp.http.magicmarker = "1";

     return (deliver);
 }

sub vcl_deliver {
    if (resp.http.magicmarker) {
        /* Remove the magic marker */
        unset resp.http.magicmarker;

        /* By definition we have a fresh object */
        set resp.http.age = "0";
    }
    return (deliver);
}