How to set Kubernetes config map and secret to mongodb environment variables - mongodb

Question

I am trying to set the two env variables of mongo namely - MONGO_INITDB_ROOT_USERNAME and MONGO_INITDB_ROOT_PASSWORD using kubernetes ConfigMap and Secret as follows:
When I don't use the config map and password, i.e. I hardcode the username and password, it works, but when I try to replace it with configmap and secret, it says
'Authentication failed.'
my username and password is the same, which is admin
Here's the yaml definition for these obects, can someone help me what is wrong?
apiVersion: v1
kind: ConfigMap
metadata:
name: mongodb-username
data:
username: admin
---
apiVersion: v1
kind: Secret
metadata:
name: mongodb-password
data:
password: YWRtaW4K
type: Opaque
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: mongodbtest
spec:
# serviceName: mongodbtest
replicas: 1
selector:
matchLabels:
app: mongodbtest
template:
metadata:
labels:
app: mongodbtest
selector: mongodbtest
spec:
containers:
- name: mongodbtest
image: mongo:3
# env:
# - name: MONGO_INITDB_ROOT_USERNAME
# value: admin
# - name: MONGO_INITDB_ROOT_PASSWORD
# value: admin
env:
- name: MONGO_INITDB_ROOT_USERNAME
valueFrom:
configMapKeyRef:
name: mongodb-username
key: username
- name: MONGO_INITDB_ROOT_PASSWORD
valueFrom:
secretKeyRef:
name: mongodb-password
key: password

Answer 1

Finally I was able to find the solution after hours, it is not something I did from kubernetes side, it is when I did base64 encode.
The correct way to encode is with following command:
echo -n 'admin' | base64
and this was the issue with me.

Answer 2

Your deployment yaml is fine, just change spec.containers[0].env to spec.containers[0].envFrom:
spec:
containers:
- name: mongodbtest
image: mongo:3
envFrom:
- configMapRef:
name: mongodb-username
- secretRef:
name: mongodb-password
That will put all keys of your secret and configmap as environment variables in the deployment.

Answer 3

apiVersion: v1
data:
MONGO_INITDB_ROOT_USERNAME: root
MONGO_INITDB_ROOT_PASSWORD : password
kind: ConfigMap
metadata:
name: mongo-cred
namespace: default
inject it to deployment like
envFrom:
- configMapRef:
name: mongo-cred
the deployment will be something like
apiVersion: apps/v1
kind: Deployment
metadata:
name: mongodbtest
spec:
# serviceName: mongodbtest
replicas: 1
selector:
matchLabels:
app: mongodbtest
template:
metadata:
labels:
app: mongodbtest
selector: mongodbtest
spec:
containers:
- name: mongodbtest
image: mongo:3
envFrom:
- configMapRef:
name: mongo-cred
if you want to save the data in secret, the secret is best practice to store data with encryption base64 and sensitive data.
envFrom:
- secretRef:
name: mongo-cred
you can create the secret with
apiVersion: v1
data:
MONGO_INITDB_ROOT_USERNAME: YWRtaW4K #base 64 encoded
MONGO_INITDB_ROOT_PASSWORD : YWRtaW4K
kind: secret
type: Opaque
metadata:
name: mongo-cred
namespace: default