func()

in otelcollector/prometheusreceiver/config.go [75:130]

• 44 lines of code
• 15 McCabe index (conditional complexity)

func (cfg *PromConfig) Validate() error {
	// 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(cfg.RemoteWriteConfigs) != 0 {
		unsupportedFeatures = append(unsupportedFeatures, "remote_write")
	}
	if len(cfg.RemoteReadConfigs) != 0 {
		unsupportedFeatures = append(unsupportedFeatures, "remote_read")
	}
	if len(cfg.RuleFiles) != 0 {
		unsupportedFeatures = append(unsupportedFeatures, "rule_files")
	}
	if len(cfg.AlertingConfig.AlertRelabelConfigs) != 0 {
		unsupportedFeatures = append(unsupportedFeatures, "alert_config.relabel_configs")
	}
	if len(cfg.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"))
	}

	scrapeConfigs, err := (*promconfig.Config)(cfg).GetScrapeConfigs()
	if err != nil {
		return err
	}
	// Since Prometheus 3.0, the scrape manager started to fail scrapes that don't have proper
	// Content-Type headers, but they provided an extra configuration option to fallback to the
	// previous behavior. We need to make sure that this option is set for all scrape configs
	// to avoid introducing a breaking change.
	for _, sc := range scrapeConfigs {
		if sc.ScrapeFallbackProtocol == "" {
			sc.ScrapeFallbackProtocol = promconfig.PrometheusText0_0_4
		}
	}

	for _, sc := range scrapeConfigs {
		if err := validateHTTPClientConfig(&sc.HTTPClientConfig); err != nil {
			return err
		}

		for _, c := range sc.ServiceDiscoveryConfigs {
			if c, ok := c.(*kubernetes.SDConfig); ok {
				if err := validateHTTPClientConfig(&c.HTTPClientConfig); err != nil {
					return err
				}
			}
		}
	}
	return nil
}