func()

in discovery/manager.go [325:433]

• 101 lines of code
• 18 McCabe index (conditional complexity)

func (m *Manager) registerProviders(cfg sd_config.ServiceDiscoveryConfig, setName string) int {
	var (
		failedCount int
		added       bool
	)
	add := func(cfg interface{}, newDiscoverer func() (Discoverer, error)) {
		t := reflect.TypeOf(cfg).String()
		for _, p := range m.providers {
			if reflect.DeepEqual(cfg, p.config) {
				p.subs = append(p.subs, setName)
				added = true
				return
			}
		}

		d, err := newDiscoverer()
		if err != nil {
			level.Error(m.logger).Log("msg", "Cannot create service discovery", "err", err, "type", t)
			failedCount++
			return
		}

		provider := provider{
			name:   fmt.Sprintf("%s/%d", t, len(m.providers)),
			d:      d,
			config: cfg,
			subs:   []string{setName},
		}
		m.providers = append(m.providers, &provider)
		added = true
	}

	for _, c := range cfg.DNSSDConfigs {
		add(c, func() (Discoverer, error) {
			return dns.NewDiscovery(*c, log.With(m.logger, "discovery", "dns")), nil
		})
	}
	for _, c := range cfg.FileSDConfigs {
		add(c, func() (Discoverer, error) {
			return file.NewDiscovery(c, log.With(m.logger, "discovery", "file")), nil
		})
	}
	for _, c := range cfg.ConsulSDConfigs {
		add(c, func() (Discoverer, error) {
			return consul.NewDiscovery(c, log.With(m.logger, "discovery", "consul"))
		})
	}
	for _, c := range cfg.MarathonSDConfigs {
		add(c, func() (Discoverer, error) {
			return marathon.NewDiscovery(*c, log.With(m.logger, "discovery", "marathon"))
		})
	}
	for _, c := range cfg.KubernetesSDConfigs {
		add(c, func() (Discoverer, error) {
			return kubernetes.New(log.With(m.logger, "discovery", "k8s"), c)
		})
	}
	for _, c := range cfg.ServersetSDConfigs {
		add(c, func() (Discoverer, error) {
			return zookeeper.NewServersetDiscovery(c, log.With(m.logger, "discovery", "zookeeper"))
		})
	}
	for _, c := range cfg.NerveSDConfigs {
		add(c, func() (Discoverer, error) {
			return zookeeper.NewNerveDiscovery(c, log.With(m.logger, "discovery", "nerve"))
		})
	}
	for _, c := range cfg.EC2SDConfigs {
		add(c, func() (Discoverer, error) {
			return ec2.NewDiscovery(c, log.With(m.logger, "discovery", "ec2")), nil
		})
	}
	for _, c := range cfg.OpenstackSDConfigs {
		add(c, func() (Discoverer, error) {
			return openstack.NewDiscovery(c, log.With(m.logger, "discovery", "openstack"))
		})
	}
	for _, c := range cfg.GCESDConfigs {
		add(c, func() (Discoverer, error) {
			return gce.NewDiscovery(*c, log.With(m.logger, "discovery", "gce"))
		})
	}
	for _, c := range cfg.AzureSDConfigs {
		add(c, func() (Discoverer, error) {
			return azure.NewDiscovery(c, log.With(m.logger, "discovery", "azure")), nil
		})
	}
	for _, c := range cfg.TritonSDConfigs {
		add(c, func() (Discoverer, error) {
			return triton.New(log.With(m.logger, "discovery", "triton"), c)
		})
	}
	if len(cfg.StaticConfigs) > 0 {
		add(setName, func() (Discoverer, error) {
			return &StaticProvider{TargetGroups: cfg.StaticConfigs}, nil
		})
	}
	if !added {
		// Add an empty target group to force the refresh of the corresponding
		// scrape pool and to notify the receiver that this target set has no
		// current targets.
		// It can happen because the combined set of SD configurations is empty
		// or because we fail to instantiate all the SD configurations.
		add(setName, func() (Discoverer, error) {
			return &StaticProvider{TargetGroups: []*targetgroup.Group{{}}}, nil
		})
	}
	return failedCount
}