Can not start nestjs project on the k8s server - node.js

Question

I am working on a nestjs project, this project can start by running, and works well :
npm run start:test
However, if I deploy the project to k8s, it will show :
[10:44:59 PM] Starting compilation in watch mode...
[10:45:22 PM] Found 0 errors. Watching for file changes.
and never show that it is running.
here is my docker :
FROM node:16 AS builder
# Create app directory
WORKDIR /app
ENV NODE_ENV='prod'
# A wildcard is used to ensure both package.json AND package-lock.json are copied
COPY package*.json ./
COPY tsconfig.build.json ./
COPY tsconfig.json ./
COPY ca-cert.pem ./
COPY prisma ./prisma/
COPY protos ./protos/
# Install app dependencies
RUN npm install
RUN npx prisma generate
COPY . .
RUN npm run build
FROM node:16-alpine
COPY --from=builder /app/node_modules ./node_modules
COPY --from=builder /app/package*.json ./
COPY --from=builder /app/dist ./dist
COPY --from=builder /app/protos ./protos
COPY --from=builder /app/tsconfig.build.json ./
COPY --from=builder /app/tsconfig.json ./
COPY --from=builder /app/prisma ./prisma
COPY --from=builder /app/ca-cert.pem ./
EXPOSE 3190
CMD [ "npm", "run", "start:test" ]
here is the package.json :
"start:test": "nest start --watch",
"start:dev": "set NODE_ENV=dev && nest start --watch",
"start:debug": "nest start --debug --watch",
"start:prod": " nest start",
Am I missing anything?

Answer 1

you should not watch the file in Kubernetes it just creates overhead, plus make sure there is proper healthcheck and memory request.
so better to change cmd to
CMD [ "npm", "run", "start" ]
but why we need to build the same package again? its pretty heavy process to build, so better to just consume dist
nest start simply ensures the project has been built (same as nest build), then invokes the node command in a portable, easy way to execute the compiled application.
NestJs already provides the correct command start:prod, but I (and Google) assumed the naked start was the call to invoke. Probably others make the same assumption. So do this instead:
{
"start": "npm run start:prod",
"start:prod": "node dist/main",
}
How to get back to point 0 of memory consumption with NestJs
If you still want to work with the existing setup then make sure these
resources:
# We usually recommend not to specify default resources and to leave this as a conscious
# choice for the user. This also increases chances charts run on environments with little
# resources, such as Minikube. If you do want to specify resources, uncomment the following
# lines, adjust them as necessary, and remove the curly braces after 'resources:'.
# limits:
# cpu: 100m
# memory: 128Mi
requests:
cpu: 1000m
memory: 2000Mi