trouble with multiple parms and RUN - docker

Question

I'm trying to get Parcel Bundler to build assets from within a Dockerfile. But its failing with:
🚨 No entries found.
at Bundler.bundle (/usr/local/lib/node_modules/parcel-bundler/src/Bundler.js:260:17)
at ERROR: Service 'webapp' failed to build: The command '/bin/sh -c parcel build index.html' returned a non-zero code:
1
Here's my dockerfile:
FROM node:8 as base
WORKDIR /usr/src/app
COPY package*.json ./
# Development
FROM base as development
ENV NODE_ENV=development
RUN npm install
RUN npm install -g parcel-bundler
WORKDIR /usr/src/app
RUN parcel build index.html <----- this is where its failing!
#RUN parcel watch index.html
# Uncomment to use Parcel's dev-server
#CMD [ "npm", "run", "parcel:dev" ]
#CMD ["npm", "start"]
# Production
FROM base as production
ENV NODE_ENV=production
COPY . .
RUN npm install --only=production
RUN npm install -g parcel-bundler
RUN npm run parcel:build
CMD [ "npm", "start" ]
NOTE: I'm trying to get this to run in Development mode first.
When I "log into" the container, I found that this command does fail:
# /bin/sh -c parcel build index.html
But this works:
# parcel build index.html
And this works:
# /bin/sh -c "parcel build index.html"
But using these variations in the Dockerfile still do NOT work:
RUN /bin/sh -c "parcel build index.html"
or
RUN ["/bin/sh", "-c", "parcel build index.html"]
NOTE: I also tried 'bash' instead of 'sh' and it still didn't work.
Any ideas why its not working?

Answer 1

bash and sh are indeed different shells, but it shouldn't matter here. -c "command argument argument" passes the entire shell string to -c, whereas -c command argument argument only passes command to -c leaving the arguments to be interpreted as additional commands to the shell you're invoking. So the right invocation is indeed:
RUN parcel build index.html
or, if you prefer to explicitly do what Docker will do when it sees RUN followed by a string, you can do:
RUN [ "bash", "-c", "parcel build index.html" ]
But I don't think any of that is your problem. Looking at your docker file, I think you're probably either:
missing some files that Bundler needs ( you've only copied in package*.json at this point )
missing some additional config that Bundler needs to function (I don't see you explictly setting 'webapp' but that might be in a package*.json file)
I'd put my money on the first one.