Error:cannot list resource "deployments" in API group "apps" at the cluster scope

Symptom:

    We have operator running in the cluster, it error out when creating deployment. The error is like

cannot list resource "deployments" in API group "apps" at the cluster scope

Solution:

It is due to the clusterrole granted to the operator lack of permssion to create deployment.... We need to add such permission in the role as well as statefulsets, secrects ....... The sample of clusterrole is below

- apiGroups:
  - ""
  resources:
  - pods
  - secrets
  - services
  - configmaps
  verbs:
  - '*'
- apiGroups:
  - apps
  resources:
  - deployments
  - statefulsets
  verbs:
  - '*'

How To Run Docker Without Sudo

• sudo groupadd docker
• sudo usermod -aG docker <username>
• logout all sessions , not only terminals but also desktop
• login again
• to test:   docker run hello-world 

Error: expected ';', found '{' in Golang

Symptom:

When we write go code for kubernetes OwnerReference , we get such error

expected ';', found '{' 

code is like

var oradbownerref = []metav1.ObjectMeta.OwnerReference{{
Kind:       apexords.TypeMeta.Kind,
APIVersion: apexords.TypeMeta.APIVersion,
Name:       apexords.ObjectMeta.Name,
UID:        apexords.ObjectMeta.UID,
}}

Solution:

It is due to OwnerReference  is on metav1 level ,not metav1.ObjectMeta level.
Correct code is

var oradbownerref = []metav1.OwnerReference{{
Kind:       apexords.TypeMeta.Kind,
APIVersion: apexords.TypeMeta.APIVersion,
Name:       apexords.ObjectMeta.Name,
UID:        apexords.ObjectMeta.UID,
}}

Example of Pod Struct with ConfigMap ImagePullSecrets in Client-GO

typeMetadata := metav1.TypeMeta{
Kind:       "Pod",
APIVersion: "v1",
}
objectMetadata := metav1.ObjectMeta{
Name: "ordspod",
Namespace:    o.UserSpecifiedNamespace,
}
configmapvolume := &corev1.ConfigMapVolumeSource{
LocalObjectReference: corev1.LocalObjectReference{Name: "test-configmap"},
}
podSpecs := corev1.PodSpec{
ImagePullSecrets: []corev1.LocalObjectReference{{
Name: "test-secret",
}},
Volumes:  []corev1.Volume{{
Name: "ords-config",
VolumeSource: corev1.VolumeSource{
ConfigMap: configmapvolume,
},
}},
Containers:    []corev1.Container{{
Name: "ordspod",
Image: "ords:v19",
VolumeMounts: []corev1.VolumeMount{{
Name: "ords-config",
MountPath: "/mnt/k8s",
}},
}},
}
pod := corev1.Pod{
TypeMeta:   typeMetadata,
ObjectMeta: objectMetadata,
Spec:       podSpecs,
}

Tip to Redirect Root of a Domain Url

Requirement:

 Sometimes we need to redirect <domain.com> (only the root)  to  <domain.com>/apex  or <domain.com>/apps

Solution:

Use RedirectMatch
examples:
RedirectMatch ^/$ /apex  or  RedirectMatch ^/$ /apps