func NewService()

in alerter/service.go [74:138]
57 lines of code
7 McCabe index (conditional complexity)

func NewService(opts *AlerterOpts) (*Alerter, error) {
	ruleStore := rules.NewStore(rules.StoreOpts{
		Region:  opts.Region,
		CtrlCli: opts.CtrlCli,
	})

	l2m := &Alerter{
		opts:      opts,
		queue:     make(chan struct{}, opts.Concurrency),
		CtrlCli:   opts.CtrlCli,
		ruleStore: ruleStore,
		clients:   make(map[string]KustoClient),
	}

	if opts.MSIID != "" {
		logger.Infof("Using MSI ID=%s", opts.MSIID)
	}

	authConfigure, err := multikustoclient.GetAuth(multikustoclient.MsiAuth(opts.MSIID), multikustoclient.TokenAuth("https://kusto.kusto.windows.net", opts.KustoToken), multikustoclient.DefaultAuth())
	if err != nil {
		return nil, fmt.Errorf("failed to get auth: %w", err)
	}
	kclient, err := multikustoclient.New(opts.KustoEndpoints, authConfigure, opts.MaxNotifications)
	if err != nil {
		return nil, err
	}

	if opts.CtrlCli == nil {
		logger.Warnf("No kusto endpoints provided, using fake kusto clients")
		fakeRule := &rules.Rule{
			Namespace: "fake-namespace",
			Name:      "FakeRule",
			Database:  "FakeDB",
			Interval:  time.Minute,
			Query:     `UnderlayNodeInfo | where Region == ParamRegion | limit 1 | project Title="test"`,
		}
		l2m.clients[fakeRule.Database] = fakeKustoClient{endpoint: "http://fake.endpoint"}
		ruleStore.Register(fakeRule)
	}

	if opts.AlertAddr == "" {
		logger.Warnf("No alert address provided, using fake alert handler")
		http.Handle("/alerts", fakeAlertHandler())
		opts.AlertAddr = fmt.Sprintf("http://localhost:%d", opts.Port)
	}

	alertCli, err := alert.NewClient(time.Minute)
	if err != nil {
		return nil, fmt.Errorf("failed to create alert client: %w", err)
	}
	l2m.alertCli = alertCli

	executor := engine.NewExecutor(
		engine.ExecutorOpts{
			AlertCli:    alertCli,
			AlertAddr:   opts.AlertAddr,
			Region:      opts.Region,
			Tags:        opts.Tags,
			KustoClient: kclient,
			RuleStore:   ruleStore,
		})

	l2m.executor = executor
	return l2m, nil
}