video-streamer-frontend: json logs for later analysis

Requested by Basti in FOSDEM/video#46

ansible/playbooks/roles/video-streamer-frontend/templates/nginx/sites-enabled/stream.fosdem.org.conf

@@ -12,6 +12,48 @@ server {
 
 	add_header Strict-Transport-Security "max-age=15552000";
 
+
+	log_format json_analytics escape=json '{'
+                    '"msec": "$msec", ' # request unixtime in seconds with a milliseconds resolution
+                    '"connection": "$connection", ' # connection serial number
+                    '"connection_requests": "$connection_requests", ' # number of requests made in connection
+                    '"pid": "$pid", ' # process pid
+                    '"request_id": "$request_id", ' # the unique request id
+                    '"request_length": "$request_length", ' # request length (including headers and body)
+                    '"remote_addr": "$remote_addr", ' # client IP
+                    '"remote_user": "$remote_user", ' # client HTTP username
+                    '"remote_port": "$remote_port", ' # client port
+                    '"time_local": "$time_local", '
+                    '"time_iso8601": "$time_iso8601", ' # local time in the ISO 8601 standard format
+                    '"request": "$request", ' # full path no arguments if the request
+                    '"request_uri": "$request_uri", ' # full path and arguments if the request
+                    '"args": "$args", ' # args
+                    '"status": "$status", ' # response status code
+                    '"body_bytes_sent": "$body_bytes_sent", ' # the number of body bytes exclude headers sent to a client
+                    '"bytes_sent": "$bytes_sent", ' # the number of bytes sent to a client
+                    '"http_referer": "$http_referer", ' # HTTP referer
+                    '"http_user_agent": "$http_user_agent", ' # user agent
+                    '"http_x_forwarded_for": "$http_x_forwarded_for", ' # http_x_forwarded_for
+                    '"http_host": "$http_host", ' # the request Host: header
+                    '"server_name": "$server_name", ' # the name of the vhost serving the request
+                    '"request_time": "$request_time", ' # request processing time in seconds with msec resolution
+                    '"upstream": "$upstream_addr", ' # upstream backend server for proxied requests
+                    '"upstream_connect_time": "$upstream_connect_time", ' # upstream handshake time incl. TLS
+                    '"upstream_header_time": "$upstream_header_time", ' # time spent receiving upstream headers
+                    '"upstream_response_time": "$upstream_response_time", ' # time spend receiving upstream body
+                    '"upstream_response_length": "$upstream_response_length", ' # upstream response length
+                    '"upstream_cache_status": "$upstream_cache_status", ' # cache HIT/MISS where applicable
+                    '"ssl_protocol": "$ssl_protocol", ' # TLS protocol
+                    '"ssl_cipher": "$ssl_cipher", ' # TLS cipher
+                    '"scheme": "$scheme", ' # http or https
+                    '"request_method": "$request_method", ' # request method
+                    '"server_protocol": "$server_protocol", ' # request protocol, like HTTP/1.1 or HTTP/2.0
+                    '"pipe": "$pipe", ' # "p" if request was pipelined, "." otherwise
+                    '"gzip_ratio": "$gzip_ratio", '
+                    '}';
+
+	access_log /var/log/nginx/fosdem.analytics.json.log json_analytics;
+
 	root /var/www/html;
 
 	index index.html;