func()

in collector/receiver/prometheusreceiver/config.go [181:257]

• 66 lines of code
• 24 McCabe index (conditional complexity)

func (cfg *Config) validatePromConfig(promConfig *promconfig.Config) error {
	if len(promConfig.ScrapeConfigs) == 0 && cfg.TargetAllocator == nil {
		return errors.New("no Prometheus scrape_configs or target_allocator set")
	}

	// Reject features that Prometheus supports but that the receiver doesn't support:
	// See:
	// * https://github.com/open-telemetry/opentelemetry-collector/issues/3863
	// * https://github.com/open-telemetry/wg-prometheus/issues/3
	unsupportedFeatures := make([]string, 0, 4)
	if len(promConfig.RemoteWriteConfigs) != 0 {
		unsupportedFeatures = append(unsupportedFeatures, "remote_write")
	}
	if len(promConfig.RemoteReadConfigs) != 0 {
		unsupportedFeatures = append(unsupportedFeatures, "remote_read")
	}
	if len(promConfig.RuleFiles) != 0 {
		unsupportedFeatures = append(unsupportedFeatures, "rule_files")
	}
	if len(promConfig.AlertingConfig.AlertRelabelConfigs) != 0 {
		unsupportedFeatures = append(unsupportedFeatures, "alert_config.relabel_configs")
	}
	if len(promConfig.AlertingConfig.AlertmanagerConfigs) != 0 {
		unsupportedFeatures = append(unsupportedFeatures, "alert_config.alertmanagers")
	}
	if len(unsupportedFeatures) != 0 {
		// Sort the values for deterministic error messages.
		sort.Strings(unsupportedFeatures)
		return fmt.Errorf("unsupported features:\n\t%s", strings.Join(unsupportedFeatures, "\n\t"))
	}

	for _, sc := range cfg.PrometheusConfig.ScrapeConfigs {
		for _, rc := range sc.MetricRelabelConfigs {
			if rc.TargetLabel == "__name__" {
				// TODO(#2297): Remove validation after renaming is fixed
				return fmt.Errorf("error validating scrapeconfig for job %v: %w", sc.JobName, errRenamingDisallowed)
			}
		}

		if sc.HTTPClientConfig.Authorization != nil {
			if err := checkFile(sc.HTTPClientConfig.Authorization.CredentialsFile); err != nil {
				return fmt.Errorf("error checking authorization credentials file %q: %w", sc.HTTPClientConfig.Authorization.CredentialsFile, err)
			}
		}

		if err := checkTLSConfig(sc.HTTPClientConfig.TLSConfig); err != nil {
			return err
		}

		for _, c := range sc.ServiceDiscoveryConfigs {
			switch c := c.(type) {
			case *kubernetes.SDConfig:
				if err := checkTLSConfig(c.HTTPClientConfig.TLSConfig); err != nil {
					return err
				}
			case *file.SDConfig:
				for _, file := range c.Files {
					files, err := filepath.Glob(file)
					if err != nil {
						return err
					}
					if len(files) != 0 {
						for _, f := range files {
							err = checkSDFile(f)
							if err != nil {
								return fmt.Errorf("checking SD file %q: %w", file, err)
							}
						}
						continue
					}
					return fmt.Errorf("file %q for file_sd in scrape job %q does not exist", file, sc.JobName)
				}
			}
		}
	}
	return nil
}