Pulse (Observability)

# Observability — Pulse
PULSE_ENABLED=true
PULSE_USERNAME=admin
PULSE_PASSWORD=pulse
PULSE_STORAGE=memory                 # "memory" (default) | "sqlite"
PULSE_STORAGE_DSN=pulse.db           # path used when PULSE_STORAGE=sqlite

// Mount Pulse observability
if cfg.PulseEnabled {
    pulseOpts := []pulse.Option{
        pulse.WithAppName(cfg.AppName),
        pulse.WithCredentials(cfg.PulseUsername, cfg.PulsePassword),
        pulse.WithExcludePaths("/studio/*", "/sentinel/*", "/docs/*", "/pulse/*"),
        pulse.WithPrometheus(),
        // Pulse's error middleware snapshots a request-body snippet for context,
        // but restores ONLY the first 4096 bytes — silently truncating larger
        // uploads/JSON. Disable capture so the full body reaches the handler.
        pulse.WithRequestBodyCaptureDisabled(),
    }
    if cfg.IsDevelopment() {
        pulseOpts = append(pulseOpts, pulse.WithDevMode())
    }
    if cfg.PulseStorage == "sqlite" && cfg.PulseStorageDSN != "" {
        pulseOpts = append(pulseOpts, pulse.WithSQLite(cfg.PulseStorageDSN))
    }

    p := pulse.Mount(context.Background(), r, db, pulseOpts...)

    // Register health checks for connected services
    if svc.Cache != nil {
        p.AddHealthCheck(pulse.HealthCheck{
            Name:     "redis",
            Type:     "redis",
            Critical: false,
            CheckFunc: func(ctx context.Context) error {
                return svc.Cache.Client().Ping(ctx).Err()
            },
        })
    }
}

p := pulse.Mount(context.Background(), r, db, pulseOpts...)

// Redis health check
p.AddHealthCheck(pulse.HealthCheck{
    Name:     "redis",
    Type:     "redis",
    Critical: false,  // non-critical = won't fail /ready
    CheckFunc: func(ctx context.Context) error {
        return redisClient.Ping(ctx).Err()
    },
})

// External API health check
p.AddHealthCheck(pulse.HealthCheck{
    Name:     "payment-api",
    Type:     "http",
    Critical: true,  // critical = will fail /ready if down
    CheckFunc: func(ctx context.Context) error {
        resp, err := http.Get("https://api.stripe.com/v1/health")
        if err != nil {
            return err
        }
        defer resp.Body.Close()
        if resp.StatusCode != 200 {
            return fmt.Errorf("status %d", resp.StatusCode)
        }
        return nil
    },
})

PULSE_STORAGE=sqlite       # switch from in-memory to persistent
PULSE_STORAGE_DSN=pulse.db # SQLite file (or ":memory:")

if cfg.PulseStorage == "sqlite" && cfg.PulseStorageDSN != "" {
    pulseOpts = append(pulseOpts, pulse.WithSQLite(cfg.PulseStorageDSN))
}