Files
coder/coderd/coderdtest/promhelp/metrics.go
Steven Masley ccfffc6911 chore: add tx metrics and logs for serialization errors (#15215)
Before db_metrics were all or nothing. Now `InTx` metrics are always recorded, and query metrics are opt in.


Adds instrumentation & logging around serialization failures in the database.
2024-10-25 12:14:15 -04:00

88 lines
2.9 KiB
Go

package promhelp
import (
"context"
"io"
"maps"
"net/http"
"net/http/httptest"
"strings"
"testing"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/client_golang/prometheus/promhttp"
ptestutil "github.com/prometheus/client_golang/prometheus/testutil"
io_prometheus_client "github.com/prometheus/client_model/go"
"github.com/stretchr/testify/require"
)
// RegistryDump returns the http page for a given registry's metrics.
// Very useful for visual debugging.
func RegistryDump(reg *prometheus.Registry) string {
h := promhttp.HandlerFor(reg, promhttp.HandlerOpts{})
rec := httptest.NewRecorder()
req, _ := http.NewRequestWithContext(context.Background(), http.MethodGet, "/", nil)
h.ServeHTTP(rec, req)
resp := rec.Result()
data, _ := io.ReadAll(resp.Body)
_ = resp.Body.Close()
return string(data)
}
// Compare can be used to compare a registry to some prometheus formatted
// text. If any values differ, an error is returned.
// If metric names are passed in, only those metrics will be compared.
// Usage: `Compare(reg, RegistryDump(reg))`
func Compare(reg prometheus.Gatherer, compare string, metricNames ...string) error {
return ptestutil.GatherAndCompare(reg, strings.NewReader(compare), metricNames...)
}
// HistogramValue returns the value of a histogram metric with the given name and labels.
func HistogramValue(t testing.TB, reg prometheus.Gatherer, metricName string, labels prometheus.Labels) *io_prometheus_client.Histogram {
t.Helper()
labeled := MetricValue(t, reg, metricName, labels)
require.NotNilf(t, labeled, "metric %q with labels %v not found", metricName, labels)
return labeled.GetHistogram()
}
// GaugeValue returns the value of a gauge metric with the given name and labels.
func GaugeValue(t testing.TB, reg prometheus.Gatherer, metricName string, labels prometheus.Labels) int {
t.Helper()
labeled := MetricValue(t, reg, metricName, labels)
require.NotNilf(t, labeled, "metric %q with labels %v not found", metricName, labels)
return int(labeled.GetGauge().GetValue())
}
// CounterValue returns the value of a counter metric with the given name and labels.
func CounterValue(t testing.TB, reg prometheus.Gatherer, metricName string, labels prometheus.Labels) int {
t.Helper()
labeled := MetricValue(t, reg, metricName, labels)
require.NotNilf(t, labeled, "metric %q with labels %v not found", metricName, labels)
return int(labeled.GetCounter().GetValue())
}
func MetricValue(t testing.TB, reg prometheus.Gatherer, metricName string, labels prometheus.Labels) *io_prometheus_client.Metric {
t.Helper()
metrics, err := reg.Gather()
require.NoError(t, err)
for _, m := range metrics {
if m.GetName() == metricName {
for _, labeled := range m.GetMetric() {
mLabels := make(prometheus.Labels)
for _, v := range labeled.GetLabel() {
mLabels[v.GetName()] = v.GetValue()
}
if maps.Equal(mLabels, labels) {
return labeled
}
}
}
}
return nil
}