Where can I see all log_append placeholders for reverse proxy?

fishnux · April 5, 2025, 10:49am

Hi,

For example, I found a reference to rp.upstream.duration_ms in the docs for the log_append directive:

But I cannot find a list of all of them… How does one knows which directives exist?

timelordx · April 5, 2025, 5:18pm

They might or should be somewhere in the documentation, but you can always find them in the source code.

github.com/caddyserver/caddy

modules/caddyhttp/reverseproxy/reverseproxy.go

5a6b2f8d1


      
          // Placeholder | Description
          // ------------|-------------
          // `{http.reverse_proxy.upstream.address}` | The full address to the upstream as given in the config
          // `{http.reverse_proxy.upstream.hostport}` | The host:port of the upstream
          // `{http.reverse_proxy.upstream.host}` | The host of the upstream
          // `{http.reverse_proxy.upstream.port}` | The port of the upstream
          // `{http.reverse_proxy.upstream.requests}` | The approximate current number of requests to the upstream
          // `{http.reverse_proxy.upstream.max_requests}` | The maximum approximate number of requests allowed to the upstream
          // `{http.reverse_proxy.upstream.fails}` | The number of recent failed requests to the upstream
          // `{http.reverse_proxy.upstream.latency}` | How long it took the proxy upstream to write the response header.
          // `{http.reverse_proxy.upstream.latency_ms}` | Same as 'latency', but in milliseconds.
          // `{http.reverse_proxy.upstream.duration}` | Time spent proxying to the upstream, including writing response body to client.
          // `{http.reverse_proxy.upstream.duration_ms}` | Same as 'upstream.duration', but in milliseconds.
          // `{http.reverse_proxy.duration}` | Total time spent proxying, including selecting an upstream, retries, and writing response.
          // `{http.reverse_proxy.duration_ms}` | Same as 'duration', but in milliseconds.
          // `{http.reverse_proxy.retries}` | The number of retries actually performed to communicate with an upstream.