Issues with installing librealsense with Balena. Unable to locate file after make install?

Question

I've been trying to setup librealsense on my Raspberry Pi4 using Balena. My docker file looks like:

FROM balenalib/raspberrypi3-ubuntu:xenial-build
RUN sudo apt-get update && sudo apt-get upgrade -y && sudo apt-get dist-upgrade -y
RUN sudo apt-get install -y python3 \
    python3-dev \
    python3-pip \
    python3-setuptools 

RUN sudo apt-get install -y git libssl-dev libusb-1.0-0-dev pkg-config libgtk-3-dev cmake libglfw3-dev build-essential 
RUN git clone https://github.com/IntelRealSense/librealsense.git
RUN cd librealsense/ && ./scripts/setup_udev_rules.sh
RUN mkdir build &&\
    cd build &&\
    cmake /librealsense/ -DBUILD_PYTHON_BINDINGS=true -DBUILD_EXAMPLES=true -DBUILD_GRAPHICAL_EXAMPLES=false -DCMAKE_BUILD_TYPE=Release &&\
    make all -j4 &&\
    sudo make all 

COPY librealsense/build/ /usr/src/app/

#switch on systemd init system in container
ENV INITSYSTEM on

WORKDIR /usr/src/app
COPY ./app/ /usr/src/app/


#Run our binary on container startup
CMD ["python3", "/usr/src/app/test_server.py"]

And my test_server.py looks like:

import sys, os
print("TEST")
rootdir = '/usr/src/app'
for f in os.listdir(rootdir):
    print(f)
print(sys.version)
try:
    user_paths = os.environ['PYTHONPATH'].split(os.pathsep)
except KeyError:
    user_paths = []
print(user_paths)
print(sys.path)
sys.path.append('/usr/src/app/')
import pyrealsense2 as rs

I am unable to import pyrealsense or copy over built .so files to put into my python application folder. I get 'librealsense/build/python does not exist' errors when I create the docker image. What am I missing in my librealsense install?

Answer 1

I think your problem is with

COPY librealsense/build/ /usr/src/app/

This would attempt a copy of 'librealsense/build' from your build context (aka host machine). You need to use 'RUN' together with 'cp', eg

RUN cp librealsense/build/ /usr/src/app/

or in a single RUN command:

RUN mkdir build &&\
    cd build &&\
    cmake /librealsense/ -DBUILD_PYTHON_BINDINGS=true -DBUILD_EXAMPLES=true -DBUILD_GRAPHICAL_EXAMPLES=false -DCMAKE_BUILD_TYPE=Release &&\
    make all -j4 &&\
    sudo make all  &&\
    cp librealsense/build/ /usr/src/app/