func newPrometheus()

in pkg/export/gcm/promtest/prometheus.go [112:164]

• 49 lines of code
• 3 McCabe index (conditional complexity)

func newPrometheus(env e2e.Environment, name string, image string, scrapeTargetAddress string, flagOverride map[string]string) *e2emon.Prometheus {
	ports := map[string]int{"http": 9090}

	f := env.Runnable(name).WithPorts(ports).Future()
	config := fmt.Sprintf(`
global:
  external_labels:
    collector: %v
scrape_configs:
- job_name: 'test'
  scrape_interval: 5s
  scrape_timeout: 5s
  static_configs:
  - targets: [%s]
  metric_relabel_configs:
  - regex: instance
    action: labeldrop
`, name, scrapeTargetAddress)
	if err := os.WriteFile(filepath.Join(f.Dir(), "prometheus.yml"), []byte(config), 0600); err != nil {
		return &e2emon.Prometheus{Runnable: e2e.NewFailedRunnable(name, fmt.Errorf("create prometheus config failed: %w", err))}
	}

	args := map[string]string{
		"--web.listen-address":               fmt.Sprintf(":%d", ports["http"]),
		"--config.file":                      filepath.Join(f.Dir(), "prometheus.yml"),
		"--storage.tsdb.path":                f.Dir(),
		"--enable-feature=exemplar-storage":  "",
		"--enable-feature=native-histograms": "",
		"--storage.tsdb.no-lockfile":         "",
		"--storage.tsdb.retention.time":      "1d",
		"--storage.tsdb.wal-compression":     "",
		"--storage.tsdb.min-block-duration":  "2h",
		"--storage.tsdb.max-block-duration":  "2h",
		"--web.enable-lifecycle":             "",
		"--log.format":                       "json",
		"--log.level":                        "info",
	}
	if flagOverride != nil {
		args = e2e.MergeFlagsWithoutRemovingEmpty(args, flagOverride)
	}

	p := e2emon.AsInstrumented(f.Init(e2e.StartOptions{
		Image:     image,
		Command:   e2e.NewCommandWithoutEntrypoint("prometheus", e2e.BuildArgs(args)...),
		Readiness: e2e.NewHTTPReadinessProbe("http", "/-/ready", 200, 200),
		User:      strconv.Itoa(os.Getuid()),
	}), "http")

	return &e2emon.Prometheus{
		Runnable:     p,
		Instrumented: p,
	}
}