Add support for PodDisruptionBudget

Add tests for PodDisruptionBudget

Author: rstefan1

Gopkg.lock

@@ -39,4 +39,14 @@ required = [
 # https://github.com/robfig/cron
 [[constraint]]
   name = "github.com/wgliang/cron"
-  revision = "79834306f6432d41449e7003710d866ceea9b40c"
+  revision = "79834306f6432d41449e7003710d866ceea9b40c"
+
+[[constraint]]
+  # Required: the root import path of the project being constrained.
+  name = "github.com/appscode/kutil"
+  # Recommended: the version constraint to enforce for the project.
+  # Note that only one of "branch", "version" or "revision" can be specified.
+  branch = "pdb"
+
+  # Optional: an alternate location (URL or import path) for the project's source.
+  source = "https://github.com/presslabs/kutil.git"

Gopkg.toml

@@ -34,11 +34,4 @@ spec:
               type: string
           required:
           - clusterName
-      required:
-      - spec
   version: v1alpha1
-status:
-  acceptedNames:
-    kind: ""
-    plural: ""
-  conditions: null

deploy/mysqlbackups.yaml

@@ -41,6 +41,10 @@ spec:
                 is removed from service.
               format: int64
               type: integer
+            minAvailable:
+              anyOf:
+              - type: string
+              - type: integer
             mysqlConf:
               description: A map[string]string that will be passed to my.cnf file.
               type: object
@@ -185,11 +189,4 @@ spec:
                   description: VolumeName is the binding reference to the PersistentVolume
                     backing this claim.
                   type: string
-      required:
-      - spec
   version: v1alpha1
-status:
-  acceptedNames:
-    kind: ""
-    plural: ""
-  conditions: null

deploy/mysqlclusters.yaml

@@ -3,12 +3,15 @@ kind: MysqlCluster
 metadata:
   name: foo
 spec:
-  replicas: 1
+  replicas: 3
   secretName: the-secret
   # mysqlVersion: 5.7
   # initBucketUri: gs://bucket_name/backup.xtrabackup.gz
   # initBucketSecretName:
 
+  ## PodDisruptionBudget
+  # minAvailable: 1
+
   ## For recurrent backups set backupSchedule with a cronjob expression
   # backupSchedule:
   # backupUri: s3://bucket_name/

examples/example-cluster.yaml

@@ -26,6 +26,7 @@ import (
 	core "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/util/intstr"
 
 	"github.com/presslabs/mysql-operator/pkg/util/options"
 )
@@ -42,7 +43,8 @@ const (
 )
 
 var (
-	opt *options.Options
+	opt                 *options.Options
+	DefaultMinAvailable intstr.IntOrString = intstr.FromString("50%")
 )
 
 func init() {
@@ -80,6 +82,10 @@ func (c *ClusterSpec) UpdateDefaults(opt *options.Options, cluster *MysqlCluster
 		c.MysqlConf = make(MysqlConf)
 	}
 
+	if c.MinAvailable == nil && c.Replicas > 1 {
+		c.MinAvailable = &DefaultMinAvailable
+	}
+
 	// configure mysql based on:
 	// https://www.percona.com/blog/2018/03/26/mysql-8-0-innodb_dedicated_server-variable-optimizes-innodb/
 
@@ -225,6 +231,8 @@ const (
 	MasterService ResourceName = "master-service"
 	// HealthyNodes is the name of a service that continas all healthy nodes
 	HealthyNodesService ResourceName = "healthy-nodes-service"
+	// PodDisruptionBudget is the name of pod disruption budget for the stateful set
+	PodDisruptionBudget ResourceName = "pdb"
 )
 
 func (c *MysqlCluster) GetNameForResource(name ResourceName) string {

pkg/apis/mysql/v1alpha1/cluster.go

@@ -155,6 +155,8 @@ const (
 	EventReasonMasterServiceUpdated       = "MasterServiceUpdated"
 	EventReasonHealthyNodesServiceFailed  = "HealthyNodesServiceFailed"
 	EventReasonHealthyNodesServiceUpdated = "HealthyNodesServiceUpdated"
+	EventReasonPDBFailed                  = "PodDisruptionBudgetFailed"
+	EventReasonPDBUpdated                 = "PodDisruptionBudgetUpdated"
 )
 
 // Event types

pkg/apis/mysql/v1alpha1/status.go

@@ -19,6 +19,7 @@ package v1alpha1
 import (
 	core "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/util/intstr"
 )
 
 // +genclient
@@ -67,6 +68,12 @@ type ClusterSpec struct {
 	InitBucketUri        string `json:"initBucketUri,omitempty"`
 	InitBucketSecretName string `json:"initBucketSecretName,omitempty"`
 
+	// The number of pods from that set that must still be available after the
+	// eviction, even in the absence of the evicted pod
+	// Defaults to 50%
+	// +optional
+	MinAvailable *intstr.IntOrString `json:"minAvailable,omitempty"`
+
 	// Specify under crontab format interval to take backups
 	// leave it empty to deactivate the backup process
 	// Defaults to ""

pkg/apis/mysql/v1alpha1/types.go

@@ -23,6 +23,7 @@ package v1alpha1
 import (
 	v1 "k8s.io/api/core/v1"
 	runtime "k8s.io/apimachinery/pkg/runtime"
+	intstr "k8s.io/apimachinery/pkg/util/intstr"
 )
 
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
@@ -101,6 +102,15 @@ func (in *ClusterCondition) DeepCopy() *ClusterCondition {
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *ClusterSpec) DeepCopyInto(out *ClusterSpec) {
 	*out = *in
+	if in.MinAvailable != nil {
+		in, out := &in.MinAvailable, &out.MinAvailable
+		if *in == nil {
+			*out = nil
+		} else {
+			*out = new(intstr.IntOrString)
+			**out = **in
+		}
+	}
 	if in.MysqlConf != nil {
 		in, out := &in.MysqlConf, &out.MysqlConf
 		*out = make(MysqlConf, len(*in))

pkg/apis/mysql/v1alpha1/zz_generated.deepcopy.go

@@ -84,6 +84,7 @@ const (
 	statusFailed   = "failed"
 	statusOk       = "ok"
 	statusSkip     = "skip"
+	statusDeleted  = "deleted"
 )
 
 type component struct {
@@ -141,6 +142,13 @@ func (f *cFactory) getComponents() []component {
 			reasonFailed:  api.EventReasonHealthyNodesServiceFailed,
 			reasonUpdated: api.EventReasonHealthyNodesServiceUpdated,
 		},
+		component{
+			alias:         "pdb",
+			name:          f.cluster.GetNameForResource(api.PodDisruptionBudget),
+			syncFn:        f.syncPDB,
+			reasonFailed:  api.EventReasonPDBFailed,
+			reasonUpdated: api.EventReasonPDBUpdated,
+		},
 	}
 }