Why do I get "Error: JWT_KEY must be defined"? - jwt

Question

I am trying to run a project that uses docker and kubernetes. When I try to run the application it gives me the following error:
> auth#1.0.0 start
> ts-node-dev src/index.ts
[INFO] 11:03:41 ts-node-dev ver. 2.0.0 (using ts-node ver. 10.8.2, typescript ver. 4.7.4)
Error: JWT_KEY must be defined
at E:\adv\shop_back\auth\src\index.ts:7:11
at Generator.next (<anonymous>)
at E:\adv\shop_back\auth\src\index.ts:8:71
at new Promise (<anonymous>)
at __awaiter (E:\adv\shop_back\auth\src\index.ts:4:12)
at start (E:\adv\shop_back\auth\src\index.ts:5:26)
at Object.<anonymous> (E:\adv\shop_back\auth\src\index.ts:25:1)
at Module._compile (node:internal/modules/cjs/loader:1105:14)
at Module._compile (E:\adv\shop_back\auth\node_modules\source-map-support\source-map-support.js:521:25)
at Module.m._compile (C:\Users\A\AppData\Local\Temp\ts-node-dev-hook-2465378030590002.js:69:33)
[ERROR] 11:03:48 Error: JWT_KEY must be defined
I tried to create a JWT_KEY using the following command:
kubectl create secret generic jwt-secret --from-literal JWT_KEY=this_is_the_jwt_key
But it responses with a new error:
error: failed to create secret secrets "jwt-secret" already exists
I remember I have used the kubectl create secret ... command previously for testing another project( although with a different expression after =, like JWT_KEY=asdf).
I don't know where these keys get stored? Why the new program doesn't work if there is a JWT_KEY already stored?
PS: I use Windows 10 machine and Docker-Desktop app.
This is my index.js file:
import mongoose from "mongoose";
import { app } from "./app";
const start = async () => {
if (!process.env.JWT_KEY) {
throw new Error("JWT_KEY must be defined");
}
if (!process.env.MONGO_URI) {
throw new Error("MONGO_URI must be defined");
}
try {
await mongoose.connect(process.env.MONGO_URI, {});
console.log("Connected to MongoDb");
} catch (err) {
console.error(err);
}
app.listen(3000, () => {
console.log("Listening on port 3000!!!!!!!!");
});
};
start();
When I run kubectl get secrets I get:
kubectl get secrets
NAME TYPE DATA AGE
jwt-secret Opaque 1 38d
This is the deployment.yaml file:
apiVersion: apps/v1
kind: Deployment
metadata:
name: auth-depl
spec:
replicas: 1
selector:
matchLabels:
app: auth
template:
metadata:
labels:
app: auth
spec:
containers:
- name: auth
image: tester/auth
env:
- name: MONGO_URI
value: 'mongodb://auth-mongo-srv:27017/auth'
- name: JWT_KEY
valueFrom:
secretKeyRef:
name: jwt-secret
key: JWT_KEY
---
apiVersion: v1
kind: Service
metadata:
name: auth-srv
spec:
selector:
app: auth
ports:
- name: auth
protocol: TCP
port: 3000
targetPort: 3000