Docker permission issue after copying files - node.js

Question

I have the following docker file
FROM ubuntu:14.04
#Install Node
RUN apt-get update -y
RUN apt-get upgrade -y
RUN apt-get install nodejs -y
RUN apt-get install nodejs-legacy -y
RUN apt-get install npm -y
RUN update-alternatives --install /usr/bin/node node /usr/bin/nodejs 10
# Create app directory
RUN mkdir -p /usr/src/app
WORKDIR /usr/src/app
# COPY distribution
COPY dist dist
COPY package.json package.json
# Substitute dependencies from environment variables
COPY entrypoint.sh /entrypoint.sh
RUN chmod +x /entrypoint.sh
ENTRYPOINT ["/entrypoint.sh"]
EXPOSE 8000
And here is the entrypoint script
#!/bin/sh
cp package.json /usr/src/app/dist/
cd /usr/src/app/dist/
echo "starting server"
exec npm start
When I run the image it fails with this error
sh: 1: http-server: not found
npm ERR! weird error 127
npm WARN This failure might be due to the use of legacy binary "node"
npm WARN For further explanations, please read
/usr/share/doc/nodejs/README.Debian
I tried various kinds of installation but still get the same error, I also tried checking if the node_modules conatins the http-server executable and it does. I tried forcing 777 permission on all the files but still running into the same error
What could be the problem?

Answer 1

It looks like you're just missing an npm install call somewhere, so the node_modules directory, nor any of its contents (like http-server) are present on the image. After the COPY package.json package.json, if you add a RUN npm install line, that might be all you need.
There are a few other things that could be simpler too though, like you probably don't need an ENTRYPOINT script to run the app and copy package.json since that's already done. Here's a simplified version of a Node Docker image I've been running with. I'm using the base Node images which, I believe, are Linux-based, but you could probably keep the Ubuntu stuff if you wanted to and it shouldn't be an issue.
FROM node:6.9.5
# Create non-root user to run app with
RUN useradd --user-group --create-home --shell /bin/bash my-app
# Set working directory
WORKDIR /home/my-app
COPY package.json ./
# Change user so that everything that's npm-installed belongs to it
USER my-app
# Install dependencies
RUN npm install --no-optional && npm cache clean
# Switch to root and copy over the rest of our code
# This is here, after the npm install, so that code changes don't trigger an un-caching
# of the npm install line
USER root
COPY .eslintrc index.js ./
COPY app ./app
RUN chown -R my-app:my-app /home/my-app
USER my-app
CMD [ "npm", "start" ]
It's good practice to make a specific user for owning/running your code and not using root, but, as I understand it, you need to use root to put files onto your image, hence the switching users a couple times here (which is what USER ... does).
I'll also note that I use this image with Docker Compose for local development, which is what the comment about code changes is referring to.