nginx: add cache to the logs, include accept header in cache key

nginx/default.conf

@@ -1,5 +1,12 @@
 vhost_traffic_status_zone;
 
+log_format cache_log '$server_name $upstream_cache_status - '
+	'$remote_addr [$time_local] '
+	'"$request" $status $body_bytes_sent '
+	'"$http_referer" "$http_user_agent" '
+	'$upstream_response_time $request_time';
+access_log /var/log/nginx/access.log cache_log;
+
 server {
 	listen 80 default_server;
 

nginx/etc/nginx.conf

@@ -66,6 +66,11 @@ http {
 		loader_files=200
 		max_size=200m;
 
+	# use the accept header since some activitypub servers
+	# have both HTML and JSON on the same URI
+        proxy_cache_key $scheme$proxy_host$uri$is_args$args$http_accept;
+
+
 	##
 	# Virtual Host Configs
 	##