Containerfile

# Use Ubuntu 18.04 - a classic base for older Python/C++ dependencies
FROM ubuntu:18.04

# Prevent prompts during package installation
ENV DEBIAN_FRONTEND=noninteractive

# 1. Setup Architecture and Core Dependencies
# We add i386 support specifically for legacy 32-bit library requirements
RUN dpkg --add-architecture i386 && \
    apt-get update && \
    apt-get install -y --no-install-recommends \
    software-properties-common \
    build-essential \
    cmake \
    swig \
    wget \
    tar \
    tcsh \
    libc6:i386 \
    libstdc++6:i386 && \
    # Add PPA for Python 3.7 (which is deprecated in standard 18.04 repos)
    add-apt-repository ppa:deadsnakes/ppa && \
    apt-get update && \
    apt-get install -y python3.7 python3.7-dev python3-pip && \
    rm -rf /var/lib/apt/lists/*

# 2. Python Environment Configuration
RUN update-alternatives --install /usr/bin/python python /usr/bin/python3.7 1 && \
    update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.7 1
RUN python -m pip install --upgrade pip

# 3. Build OpenBabel from Source
WORKDIR /opt
RUN wget https://github.com/openbabel/openbabel/archive/refs/tags/openbabel-3-1-1.tar.gz -O openbabel.tar.gz && \
    tar -xzf openbabel.tar.gz && \
    rm openbabel.tar.gz && \
    cd openbabel-openbabel-3-1-1 && \
    mkdir build && \
    cd build && \
    cmake .. -DPYTHON_BINDINGS=ON -DPYTHON_EXECUTABLE=/usr/bin/python3.7 && \
    make -j$(nproc) && \
    make install

# 4. Set Environment Variables for Compiled Libraries
ENV PYTHONPATH=/usr/local/lib/python3.7/site-packages
ENV LD_LIBRARY_PATH=/usr/local/lib

# 5. Application Setup
WORKDIR /app
COPY dependencies.txt .
RUN pip install --no-cache-dir -r dependencies.txt

COPY . . 
RUN pip install -e .

# Define default command (optional)
CMD ["python3"]