operator: Refactor CreateOrUpdateLokiStack handler

operator/internal/handlers/internal/gateway/base_domain.go

@@ -6,19 +6,18 @@ import (
 	"github.com/ViaQ/logerr/v2/kverrors"
 	configv1 "github.com/openshift/api/config/v1"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
-	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 
 	lokiv1 "github.com/grafana/loki/operator/apis/loki/v1"
 	"github.com/grafana/loki/operator/internal/external/k8s"
 	"github.com/grafana/loki/operator/internal/status"
 )
 
-// GetOpenShiftBaseDomain returns the cluster DNS base domain on OpenShift
+// getOpenShiftBaseDomain returns the cluster DNS base domain on OpenShift
 // clusters to auto-create redirect URLs for OpenShift Auth or an error.
 // If the config.openshift.io/DNS object is not found the whole lokistack
 // resoure is set to a degraded state.
-func GetOpenShiftBaseDomain(ctx context.Context, k k8s.Client, req ctrl.Request) (string, error) {
+func getOpenShiftBaseDomain(ctx context.Context, k k8s.Client) (string, error) {
 	var cluster configv1.DNS
 	key := client.ObjectKey{Name: "cluster"}
 	if err := k.Get(ctx, key, &cluster); err != nil {

operator/internal/handlers/internal/gateway/gateway.go

@@ -0,0 +1,87 @@
+package gateway
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/go-logr/logr"
+
+	configv1 "github.com/grafana/loki/operator/apis/config/v1"
+	lokiv1 "github.com/grafana/loki/operator/apis/loki/v1"
+	"github.com/grafana/loki/operator/internal/external/k8s"
+	"github.com/grafana/loki/operator/internal/handlers/internal/openshift"
+	"github.com/grafana/loki/operator/internal/manifests"
+	"github.com/grafana/loki/operator/internal/status"
+)
+
+// BuildOptions returns the options needed to generate Kubernetes resource
+// manifests for the lokistack-gateway.
+// The returned error can be a status.DegradedError in the following cases:
+//   - The tenants spec is missing.
+//   - The tenants spec is invalid.
+func BuildOptions(ctx context.Context, log logr.Logger, k k8s.Client, stack *lokiv1.LokiStack, fg configv1.FeatureGates) (string, manifests.Tenants, error) {
+	var (
+		err        error
+		baseDomain string
+		secrets    []*manifests.TenantSecrets
+		configs    map[string]manifests.TenantConfig
+		tenants    manifests.Tenants
+	)
+
+	if !fg.LokiStackGateway {
+		return "", tenants, nil
+	}
+
+	if stack.Spec.Tenants == nil {
+		return "", tenants, &status.DegradedError{
+			Message: "Invalid tenants configuration: TenantsSpec cannot be nil when gateway flag is enabled",
+			Reason:  lokiv1.ReasonInvalidTenantsConfiguration,
+			Requeue: false,
+		}
+	}
+
+	if err = validateModes(stack); err != nil {
+		return "", tenants, &status.DegradedError{
+			Message: fmt.Sprintf("Invalid tenants configuration: %s", err),
+			Reason:  lokiv1.ReasonInvalidTenantsConfiguration,
+			Requeue: false,
+		}
+	}
+
+	switch stack.Spec.Tenants.Mode {
+	case lokiv1.OpenshiftLogging, lokiv1.OpenshiftNetwork:
+		baseDomain, err = getOpenShiftBaseDomain(ctx, k)
+		if err != nil {
+			return "", tenants, err
+		}
+
+		if stack.Spec.Proxy == nil {
+			// If the LokiStack has no proxy set but there is a cluster-wide proxy setting,
+			// set the LokiStack proxy to that.
+			ocpProxy, proxyErr := openshift.GetProxy(ctx, k)
+			if proxyErr != nil {
+				return "", tenants, proxyErr
+			}
+
+			stack.Spec.Proxy = ocpProxy
+		}
+	default:
+		secrets, err = getTenantSecrets(ctx, k, stack)
+		if err != nil {
+			return "", tenants, err
+		}
+	}
+
+	// extract the existing tenant's id, cookieSecret if exists, otherwise create new.
+	configs, err = getTenantConfigFromSecret(ctx, k, stack)
+	if err != nil {
+		log.Error(err, "error in getting tenant secret data")
+	}
+
+	tenants = manifests.Tenants{
+		Secrets: secrets,
+		Configs: configs,
+	}
+
+	return baseDomain, tenants, nil
+}