Second attempt at conditionally slicing requests

overlay/etc/nginx/conf.d/31_slice_maps.conf

@@ -1,4 +1,15 @@
-map "${cacheidentifier}${http_range}" $slice_range_actual {
+map "${cacheidentifier}${http_range}" $lcn_use_slicing {
+    default 1; # Use the calculated slice range by default
+    ~steam$ 0; # Disable slicing for Steam when the client request isn't a range, as not all CDN nodes accept range requests
+}
+
+# map of location names to use for sliced/unsliced requests
+map "${lcn_use_slicing}" $lcn_request_location_name {
+    1 "@lcn_sliced_request";
+    0 "@lcn_unsliced_request";
+}
+
+map "${cacheidentifier}${http_range}" $lcn_slice_range {
     default $slice_range; # Use the calculated slice range by default
     ~steam$ ""; # Disable slicing for Steam when the client request isn't a range, as not all CDN nodes accept range requests
 }

overlay/etc/nginx/sites-available/cache.conf.d/10_root.conf

@@ -1,7 +1,20 @@
   resolver UPSTREAM_DNS ipv6=off;
 
   location / {
+    # use the location block named by $lcn_request_location_name - set in 31_slice_maps.conf - to service the request
+    try_files "" $lcn_request_location_name;
+  }
+
+  location @lcn_sliced_request {
+    slice 1m;
 
     include /etc/nginx/sites-available/cache.conf.d/root/*.conf;
 
+    # $lcn_slice_range is set from the map in 31_slice_maps.conf
+    proxy_set_header  Range $lcn_slice_range;
+  }
+
+  location @lcn_unsliced_request {
+    # slice directive deliberately not included
+    include /etc/nginx/sites-available/cache.conf.d/root/*.conf;
   }

overlay/etc/nginx/sites-available/cache.conf.d/root/20_cache.conf

@@ -1,11 +1,8 @@
     # Cache Location
-    slice 1m;
     proxy_cache generic;
 
     proxy_ignore_headers Expires Cache-Control;
     proxy_cache_valid 200 206 CACHE_MAX_AGE;
-    # $slice_range_actual is set from the map in 31_slice_maps.conf
-    proxy_set_header  Range $slice_range_actual;
 
     # Only download one copy at a time and use a large timeout so
     # this really happens, otherwise we end up wasting bandwith

overlay/etc/nginx/sites-available/cache.conf.d/root/30_cache_key.conf

@@ -1 +1 @@
-    proxy_cache_key      $cacheidentifier$uri$slice_range_actual;
+    proxy_cache_key      $cacheidentifier$uri$lcn_slice_range;

overlay/hooks/entrypoint-pre.d/10_setup.sh

@@ -16,7 +16,7 @@ sed -i "s/CACHE_DISK_SIZE/${CACHE_DISK_SIZE}/" /etc/nginx/conf.d/20_proxy_cache_
 sed -i "s/MIN_FREE_DISK/${MIN_FREE_DISK}/" /etc/nginx/conf.d/20_proxy_cache_path.conf
 sed -i "s/CACHE_MAX_AGE/${CACHE_MAX_AGE}/" /etc/nginx/conf.d/20_proxy_cache_path.conf
 sed -i "s/CACHE_MAX_AGE/${CACHE_MAX_AGE}/"    /etc/nginx/sites-available/cache.conf.d/root/20_cache.conf
-sed -i "s/slice 1m;/slice ${CACHE_SLICE_SIZE};/" /etc/nginx/sites-available/cache.conf.d/root/20_cache.conf
+sed -i "s/slice 1m;/slice ${CACHE_SLICE_SIZE};/" /etc/nginx/sites-available/cache.conf.d/10_root.conf
 sed -i "s/UPSTREAM_DNS/${UPSTREAM_DNS}/"    /etc/nginx/sites-available/cache.conf.d/10_root.conf
 sed -i "s/UPSTREAM_DNS/${UPSTREAM_DNS}/"    /etc/nginx/sites-available/upstream.conf.d/10_resolver.conf
 sed -i "s/UPSTREAM_DNS/${UPSTREAM_DNS}/"    /etc/nginx/stream-available/10_sni.conf