check resource requests also on UPDATE and SYNC + update docs

pkg/cluster/cluster.go

@@ -228,7 +228,7 @@ func (c *Cluster) Create() error {
 	c.setStatus(acidv1.ClusterStatusCreating)
 
 	if err = c.validateResources(&c.Spec); err != nil {
-		return fmt.Errorf("unsufficient ressources: %v", err)
+		return fmt.Errorf("insufficient resources specified: %v", err)
 	}
 
 	for _, role := range []PostgresRole{Master, Replica} {
@@ -595,6 +595,12 @@ func (c *Cluster) Update(oldSpec, newSpec *acidv1.Postgresql) error {
 		}
 	}
 
+	// check pod resources and volume size and cancel update if they are too low
+	if err := c.validateResources(&c.Spec); err != nil {
+		updateFailed = true
+		return fmt.Errorf("insufficient resources specified: %v", err)
+	}
+
 	// Volume
 	if oldSpec.Spec.Size != newSpec.Spec.Size {
 		c.logger.Debugf("syncing persistent volumes")

pkg/cluster/sync.go

@@ -34,6 +34,11 @@ func (c *Cluster) Sync(newSpec *acidv1.Postgresql) error {
 		}
 	}()
 
+	if err = c.validateResources(&c.Spec); err != nil {
+		err = fmt.Errorf("insufficient resources specified: %v", err)
+		return err
+	}
+
 	if err = c.initUsers(); err != nil {
 		err = fmt.Errorf("could not init users: %v", err)
 		return err

pkg/controller/controller.go

@@ -6,7 +6,7 @@ import (
 	"sync"
 
 	"github.com/sirupsen/logrus"
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	rbacv1beta1 "k8s.io/api/rbac/v1beta1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
@@ -111,7 +111,7 @@ func (c *Controller) initOperatorConfig() {
 
 	if c.opConfig.SetMemoryRequestToLimit {
 
-		isSmaller, err := util.RequestIsSmallerThanLimit(c.opConfig.DefaultMemoryRequest, c.opConfig.DefaultMemoryLimit)
+		isSmaller, err := util.IsSmallerQuantity(c.opConfig.DefaultMemoryRequest, c.opConfig.DefaultMemoryLimit)
 		if err != nil {
 			panic(err)
 		}
@@ -120,7 +120,7 @@ func (c *Controller) initOperatorConfig() {
 			c.opConfig.DefaultMemoryRequest = c.opConfig.DefaultMemoryLimit
 		}
 
-		isSmaller, err = util.RequestIsSmallerThanLimit(c.opConfig.ScalyrMemoryRequest, c.opConfig.ScalyrMemoryLimit)
+		isSmaller, err = util.IsSmallerQuantity(c.opConfig.ScalyrMemoryRequest, c.opConfig.ScalyrMemoryLimit)
 		if err != nil {
 			panic(err)
 		}

pkg/util/util_test.go

@@ -159,10 +159,10 @@ func TestIsSmallerQuantity(t *testing.T) {
 	for _, tt := range requestIsSmallerQuantityTests {
 		res, err := IsSmallerQuantity(tt.request, tt.limit)
 		if err != nil {
-			t.Errorf("RequestIsSmallerThanLimit returned unexpected error: %#v", err)
+			t.Errorf("IsSmallerQuantity returned unexpected error: %#v", err)
 		}
 		if res != tt.out {
-			t.Errorf("RequestIsSmallerThanLimit expected: %#v, got: %#v", tt.out, res)
+			t.Errorf("IsSmallerQuantity expected: %#v, got: %#v", tt.out, res)
 		}
 	}
 }