Not able to use port 3002 in docker file for React Js-CodePudding

I want to use other port like 3002 rather than 3000 in my react js app but I am not able to use it. can anyone please help me on this ?

Please note I don't want to change in the package.json to update the port -> "start" : "PORT=3002 react-scripts start"

I want to specifically change only in Dockerfile

Is there any way by which we can change in CMD to supply the PORT ?

FROM node:16.13.2


ARG DEFAULT_PORT 3002

ENV PORT ${DEFAULT_PORT}

# set working directory
WORKDIR /app

# add `/app/node_modules/.bin` to $PATH
ENV PATH /app/node_modules/.bin:$PATH

# install app dependencies
COPY package.json ./

COPY package-lock.json ./

RUN npm install

# add app
COPY . ./

#RUN export PORT=3002 -> with this one also not working

# start app
CMD ["npm", "start"]

CodePudding user response：

Please try below command.

CMD PORT=3002 npm start

It should change the port, don't use CMD ["PORT=3002", "npm", "start"]

CodePudding user response：

try to run

npx kill-port 3002

then start it again cause now that port is in use for some other project

CodePudding user response：

to use a manual port instead of a default port you can use this command

CMD PORT=3002 npm start instead of npm start