Files
graphql-monitoring-proxy/monitoring/nil_safety_test.go
T
lukaszraczylo 7e0d1e19b1 fix(circuitbreaker): guard nil monitoring to prevent boot panic
Starting with ENABLE_CIRCUIT_BREAKER=true panicked at boot: parseConfig -> initCircuitBreaker registers a metrics gauge, but cfg.Monitoring is assigned later by StartMonitoringServer, so the registration dereferenced a nil *MetricsSetup.

Add nil-receiver guards to the MetricsSetup registration methods (RegisterMetricsGauge/GaugeFunc/Counter, RegisterFloatCounter, RegisterMetricsSummary/Histogram), matching their existing 'return a dummy to prevent panics' contract. The guard is a no-op for non-nil receivers, so existing callers are unaffected. The breaker and the admin dashboard (which reads gobreaker state directly) keep working.

Add regression tests for the nil-receiver methods and for initCircuitBreaker with nil monitoring.
2026-06-21 02:48:37 +01:00

26 lines
956 B
Go

package libpack_monitoring
import (
"testing"
"github.com/stretchr/testify/require"
)
// TestRegistrationMethods_NilReceiver_NoPanic verifies that the metric
// registration methods tolerate a nil *MetricsSetup receiver. Callers may
// register metrics before the monitoring server has constructed the global
// MetricsSetup (e.g. circuit breaker init during config parsing); these
// methods must return a non-nil dummy instead of panicking.
func TestRegistrationMethods_NilReceiver_NoPanic(t *testing.T) {
var ms *MetricsSetup // nil
require.NotPanics(t, func() {
require.NotNil(t, ms.RegisterMetricsGauge("g", nil, 1))
require.NotNil(t, ms.RegisterMetricsGaugeFunc("gf", nil, func() float64 { return 1 }))
require.NotNil(t, ms.RegisterMetricsCounter("c", nil))
require.NotNil(t, ms.RegisterFloatCounter("fc", nil))
require.NotNil(t, ms.RegisterMetricsSummary("s", nil))
require.NotNil(t, ms.RegisterMetricsHistogram("h", nil))
})
}