ui: fix nginx conf

Signed-off-by: Viktor Login <[email protected]>

Author: batazor

boundaries/ui/ops/conf/nginx.conf

@@ -1,80 +1,75 @@
-# One worker process per CPU core
+# Load the OpenTelemetry (OTel) module for NGINX
 load_module modules/ngx_otel_module.so;
-worker_processes auto;
-pid /tmp/nginx.pid;
-env OTEL_EXPORTER_OTLP_ENDPOINT;
+
+worker_processes auto;        # Use one worker per CPU core
+pid /tmp/nginx.pid;           # PID file in /tmp (container-friendly)
+env OTEL_EXPORTER_OTLP_ENDPOINT;  # Inherit the environment variable into NGINX
 
 events {
-    worker_connections 2048;
-    use epoll;
-    multi_accept on;
+    worker_connections 2048;  # Max connections per worker
+    use epoll;                # Efficient Linux event notification mechanism
+    multi_accept on;          # Accept multiple connections at once
 }
 
 http {
-    map $env_OTEL_EXPORTER_OTLP_ENDPOINT $otel_exporter_endpoint {
-        default $env_OTEL_EXPORTER_OTLP_ENDPOINT;
+    # Map the environment variable to a configuration variable, with fallback
+    map $OTEL_EXPORTER_OTLP_ENDPOINT $otel_exporter_endpoint {
+        default $OTEL_EXPORTER_OTLP_ENDPOINT;
         ""      "http://grafana-tempo.grafana:4317";
     }
 
+    # OpenTelemetry exporter configuration
     otel_exporter {
-        endpoint $otel_exporter_endpoint;
-        interval 1s;
-        batch_size 2048;
-    }
-
-    map $request_time $adaptive_sample {
-        ~^0\.[0-4]  0.001;
-        ~^0\.[5-9]  0.01;
-        ~^[1-2]\.   0.1;
-        default     1.0;
+        endpoint $otel_exporter_endpoint;  # Send spans to this endpoint
+        interval 1s;                       # Flush interval
+        batch_size 2048;                   # Maximum spans per batch
     }
 
-    otel_service_name "shortlink-ui";
-    otel_trace on;
-    otel_trace_context propagate;
+    otel_service_name "shortlink-ui";  # Service name seen in tracing backend
+    otel_trace on;                      # Enable tracing for HTTP requests
+    otel_trace_context propagate;       # Propagate W3C trace context to upstream
 
-    # Temp paths (safe for container environments)
+    # Temporary file paths (suitable for containers)
     proxy_temp_path       /tmp/proxy_temp;
     client_body_temp_path /tmp/client_temp;
     fastcgi_temp_path     /tmp/fastcgi_temp;
     uwsgi_temp_path       /tmp/uwsgi_temp;
     scgi_temp_path        /tmp/scgi_temp;
 
-    # Static file optimizations
+    # Static file & connection optimisations
     sendfile        on;
     tcp_nopush      on;
     tcp_nodelay     on;
     keepalive_timeout 65s;
     keepalive_requests 1000;
 
-    # MIME types
     include       /etc/nginx/mime.types;
     default_type  application/octet-stream;
 
-    # Logging
+    # Logging in JSON format, including trace IDs
     map $upstream_response_time $temprt {
         default $upstream_response_time;
         ""      0;
     }
 
     log_format json escape=json
-        '{ "@timestamp": "$time_iso8601", '
-        '"remote_addr": "$remote_addr", '
-        '"body_bytes_sent": "$body_bytes_sent", '
-        '"status": $status, '
-        '"request": "$request", '
-        '"url": "$uri", '
-        '"request_method": "$request_method", '
-        '"response_time": $temprt, '
-        '"trace_id": "$otel_trace_id", '
-        '"span_id": "$otel_span_id", '
-        '"http_referrer": "$http_referer", '
-        '"http_user_agent": "$http_user_agent" }';
+        '{ "@timestamp":"$time_iso8601",'
+        '"remote_addr":"$remote_addr",'
+        '"body_bytes_sent":"$body_bytes_sent",'
+        '"status":$status,'
+        '"request":"$request",'
+        '"url":"$uri",'
+        '"request_method":"$request_method",'
+        '"response_time":"$temprt",'
+        '"trace_id":"$otel_trace_id",'
+        '"span_id":"$otel_span_id",'
+        '"http_referrer":"$http_referer",'
+        '"http_user_agent":"$http_user_agent"}';
 
-    access_log /var/log/nginx/access.log json;
-    error_log  /var/log/nginx/error.log warn;
+    access_log  /var/log/nginx/access.log json;
+    error_log   /var/log/nginx/error.log warn;
 
-    # Gzip compression (no double-compress on already-compressed formats)
+    # Gzip compression settings
     gzip              on;
     gzip_min_length   10240;
     gzip_proxied      any;
@@ -88,5 +83,6 @@ http {
         application/javascript
         image/svg+xml;
 
+    # Include other server/location configs
     include /etc/nginx/conf.d/*;
 }