Why `~/.bashrc` is not executed when run docker container?

I have a docker file as below. launch.sh is the entry point in this docker image.

FROM ubuntu:16.04
USER root

RUN apt-get update && apt-get install -y 
        curl 
        vim 
        net-tools 
        git 
        iputils-ping 
        wget

RUN apt-get install -y python
RUN apt-get update && apt-get install -y gcc g++ make libgflags-dev libsnappy-dev zlib1g-dev libbz2-dev liblz4-dev libzstd-dev

RUN curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.33.11/install.sh | bash

ENV NVM_DIR /root/.nvm
RUN . $NVM_DIR/nvm.sh && 
  nvm install 7.9.0 && npm install -g [email protected]

ADD ./Docker/launch.sh /workspace/

CMD ["/bin/sh", "/workspace/launch.sh"]

The content of launch.sh is:

#!/bin/bash

cd /workspace/demo
npm install
node index.js

when I run the docker container: docker run IMAGE_NAME, I got this error:

npm: not found
node: not found

The node in this image is managed by nvm which has been installed and its script has been set on /root/.bashrc file. But I don’t know why it can’t find the nodejs commands. But if I run the container by docker run -it IMAGE_NAME bash, then manually run workspace/launch.sh command, everything works fine. It seems the ~/.bashrc is not executed when run the image. How can I let the container source .bashrc?

Source: StackOverflow