func reconcileEnrollmentToken()

in pkg/controller/agent/fleet.go [300:356]
48 lines of code
16 McCabe index (conditional complexity)

func reconcileEnrollmentToken(params Params, api fleetAPI) (EnrollmentAPIKey, error) {
	defer api.client.CloseIdleConnections()
	agent := params.Agent
	ctx := params.Context
	// do we have an existing token that we have rolled out previously?
	tokenName, exists := agent.Annotations[FleetTokenAnnotation]
	if !exists {
		// setup fleet to create default policies (and tokens)
		if err := api.setupFleet(ctx); err != nil {
			return EnrollmentAPIKey{}, err
		}
	}
	// what policy should we enroll this agent in?
	policyID, err := findPolicyID(ctx, params.EventRecorder, agent, api)
	if err != nil {
		return EnrollmentAPIKey{}, err
	}
	if exists {
		// get the enrollment token identified by the annotation
		key, err := api.getEnrollmentAPIKey(ctx, tokenName)
		// the annotation might contain corrupted or no longer valid information
		if err != nil && commonhttp.IsNotFound(err) {
			goto FindOrCreate
		}
		if err != nil {
			return EnrollmentAPIKey{}, err
		}
		// if the token is valid and for the right policy we are done here
		if key.Active && key.PolicyID == policyID {
			return key, nil
		}
	}

FindOrCreate:
	key, err := api.findEnrollmentAPIKey(ctx, policyID)
	if err != nil && errors.Is(err, errNoMatchingTokenFound) {
		ulog.FromContext(ctx).Info("Could not find existing Fleet enrollment API keys, creating new one", "error", err.Error())
		key, err = api.createEnrollmentAPIKey(ctx, policyID)
		if err != nil {
			return EnrollmentAPIKey{}, err
		}
	}
	if err != nil {
		return EnrollmentAPIKey{}, err
	}

	// this potentially creates conflicts we could introduce reconciler state similar to the ES controller and handle it  on the top level
	if agent.Annotations == nil {
		agent.Annotations = map[string]string{}
	}
	agent.Annotations[FleetTokenAnnotation] = key.ID
	err = params.Client.Update(ctx, &agent)
	if err != nil {
		return EnrollmentAPIKey{}, err
	}
	return key, nil
}