fn on_event()

in hf_xet/src/log_buffer.rs [199:244]

• 44 lines of code
• 5 McCabe index (conditional complexity)

    fn on_event(&self, event: &tracing::Event<'_>, _ctx: tracing_subscriber::layer::Context<'_, S>) {
        let mut buffer = self.buffer.lock().unwrap();
        let mut http_headers = HeaderMap::new();

        {
            let mut user_agent = self.telemetry_versions.clone();
            let mut visitor = |field: &tracing::field::Field, value: &dyn std::fmt::Debug| {
                user_agent.push_str(&format!("{}/{:?}; ", field.name(), value));
            };
            event.record(&mut visitor);
            user_agent = user_agent.replace("\"", "");
            if let Ok(header_value) = HeaderValue::from_str(&user_agent) {
                http_headers.insert("User-Agent", header_value);
            } else {
                self.stats.records_refused.fetch_add(1, Ordering::Relaxed);
                return;
            }
        }
        let serializable: SerializableHeaders = (&http_headers).into();
        if let Ok(serialized_headers) = serde_json::to_string(&serializable) {
            if let Ok(reserved) = buffer.reserve(serialized_headers.len()) {
                if reserved.len() < serialized_headers.len() {
                    // log goes to /dev/null if not enough free space
                    self.stats.records_refused.fetch_add(1, Ordering::Relaxed);
                    self.stats
                        .bytes_refused
                        .fetch_add(serialized_headers.len() as u64, Ordering::Relaxed);
                    buffer.commit(0);
                } else {
                    self.stats.records_written.fetch_add(1, Ordering::Relaxed);
                    self.stats
                        .bytes_written
                        .fetch_add(serialized_headers.len() as u64, Ordering::Relaxed);
                    reserved[..serialized_headers.len()].copy_from_slice(serialized_headers.as_bytes());
                    buffer.commit(serialized_headers.len());
                }
            } else {
                self.stats.records_refused.fetch_add(1, Ordering::Relaxed);
                self.stats
                    .bytes_refused
                    .fetch_add(serialized_headers.len() as u64, Ordering::Relaxed);
            }
        } else {
            self.stats.records_refused.fetch_add(1, Ordering::Relaxed);
        }
    }