kubernetes-postgres

#CUSTOM PASSWORD
----------------
https://scottlinux.com/2012/09/01/encode-or-decode-base64-from-the-command-line/

To encode text to base64, use the following syntax:

$ echo -n 'scottlinux.com rocks' | base64
c2NvdHRsaW51eC5jb20gcm9ja3MK
To decode, use base64 -d. To decode base64, use a syntax like the following:

$ echo -n c2NvdHRsaW51eC5jb20gcm9ja3MK | base64 -d
scottlinux.com rocks



############################################################################################
echo -n 'cloudelligent.com asim' | base64

Y2xvdWRlbGxpZ2VudC5jb20gYXNpbQ==



echo Y2xvdWRlbGxpZ2VudC5jb20gYXNpbQ== | base64 -d

cloudelligent.com asim
#############################################################################################

#RANDOM PASSWORD
----------------
https://github.com/groovemonkey/project-based-kubernetes/blob/master/projects/wordpress/secrets/wp-mysql-secrets.yaml

echo && PASS=$(cat /dev/urandom | env LC_CTYPE=C tr -dc [:alnum:] | head -c 15) && echo "Password: ${PASS}" && echo "Base64 encoded:" $(echo ${PASS} | base64)



##### We are going to create a postgres-secret.yaml #####

kubectl apply -f postgres-secret.yaml

nano postgres-secret.yaml

apiVersion: v1

# This is a workaround for the broken  --from-file kubernetes abstraction
# which doesn't sanely handle .env files
# MYSQL_DATABASE and MYSQL_USER are both set to 'wordpress'

# INSTRUCTIONS:
# Generate a MYSQL_PASSWORD and MYSQL_ROOT_PASSWORD and then save this file before using it.
# e.g.
# echo && PASS=$(cat /dev/urandom | env LC_CTYPE=C tr -dc [:alnum:] | head -c 15) && echo "Password: ${PASS}" && echo "Base64 encoded:" $(echo ${PASS} | base64)

kind: Secret
metadata:
  name: jira-postgres-db-secrets
  namespace: default

type: Opaque

data:
  # Example if you need multiple values
  # MYSQL_DATABASE: d29yZHByZXNzCg==
  # MYSQL_USER: d29yZHByZXNzCg==
  # MYSQL_PASSWORD: SXhCMzRxRXF0dERubXpR

  #https://hub.docker.com/_/postgres

  # This is base64 encoded -- the real password is NGiJi6A46YJTjTx
  POSTGRES_PASSWORD: TkdpSmk2QTQ2WUpUalR4


--------------------------------------------------------------------

kubectl get secrets


#https://github.com/groovemonkey/project-based-kubernetes/tree/master/projects/wordpress/manifests

1. (A) kubectl apply -f storage.yaml

nano storage.yaml

kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
  name: postgres-db-block-storage
provisioner: kubernetes.io/aws-ebs
allowVolumeExpansion: true
parameters:
  type: gp2
  zones: us-west-2b







(B) kubectl apply -f postgres-volume-claim.yaml


nano postgres-volume-claim.yaml

---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: postgres-volume
spec:
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 1Gi
  storageClassName: postgres-db-block-storage


2. kubectl apply -f postgres-replica-set.yaml

#https://www.bmc.com/blogs/kubernetes-postgresql/

nano postgres-replica-set.yaml

---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: postgres
  # labels so that we can bind a Service to this Pod
  labels:
    app: postgres
spec:
  replicas: 1
  selector:
    matchLabels:
      app: postgres
  template:
    metadata:
      labels:
        app: postgres
    spec:
      containers:
      - name: database
        image: postgres
        
     #   args:
          # We need this to prevent mysql from throwing up -- our DO volume will be mounted here
      #    - "--ignore-db-dir=lost+found"
        # A nice way to get a whole bunch of values from a k8s secret into a container's  environment variables
        envFrom:
          - secretRef:
              name: jira-postgres-db-secrets
        ## The old way (one for each value):
        # env:
        # # Use a secret, avoid having plaintext passwords all over your configs
        # - name: POSTGRES_PASSWORD
        #   valueFrom:
        #     secretKeyRef:
        #       name: wp-db-secrets
        #       key: POSTGRES_PASSWORD
        livenessProbe:
          tcpSocket:
            port: 5432
        ports:
          - containerPort: 5432
        volumeMounts:
        - name: postgres-data
          mountPath: /var/lib/postgresql/data
          subPath: postgres
      volumes:
      - name: postgres-data
        persistentVolumeClaim:
          claimName: postgres-volume


3. kubectl apply -f postgres-service.yaml

nano postgres-service.yaml

---
apiVersion: v1
kind: Service
metadata:
  name: postgres
spec:
  ports:
  - port: 5432
    protocol: TCP
  selector:
    app: postgres


4. kubectl get replicasets
   kubectl get secrets
   kubectl get pods
   kubectl get services
   kubectl get ep ---> end point

5. pgAdmin Deployment ---> Note: postgres uses pgadmin not phpmyadmin

# useful link ---> https://blog.toadworld.com/2017/03/29/postgresql-database-with-kubernetes-for-performance-and-collaboration

# postgres Command line create data-base and user
#https://www.cyberciti.biz/faq/howto-add-postgresql-user-account/

kubectl get pods -o wide

kubectl exec -it postgres-788ffb6846-rsbcf -- bash

Step # 1: Add a Linux/UNIX user called tom
Type the following commands to create a UNIX/Linux user called tom:
# adduser asim	
# passwd asim

Step # 2: Becoming a superuser
su - postgres

Step #3: Now connect to database server
Type the following command
$ psql template1

OR
$ psql -d template1 -U postgres

Step #4: Add a user called asim

CREATE USER asim WITH PASSWORD 'asim';

Step #5: Add a database called jerry

CREATE DATABASE jiradb;

Now grant all privileges on database
template1=# GRANT ALL PRIVILEGES ON DATABASE jiradb to asim;

Type \q to quit:
template1=# \q

Step #6: Test asim user login

In order to login as asim you need to type following commands. Login as asim or use su command:
$ su asim
$ psql -d jiradb -U asim


Output:

Welcome to psql 7.4.16, the PostgreSQL interactive terminal.

Type:  \\copyright for distribution terms
       \\h for help with SQL commands
       \\? for help on internal slash commands
       \\g or terminate with semicolon to execute query
       \\q to quit

jiradb=>