treecript-builder.def

Bootstrap: docker
From: quay.io/pypa/manylinux_2_28_x86_64

# Build-time variables, equivalent to the Dockerfile's ARG. Override at
# build time with --build-arg NAME=value (see the build command below).
%arguments
    PYVER=3.13.9
    TREECRIPT_GIT_URL=https://github.com/inab/treecript.git
    TREECRIPT_REF=exec

# Copies constraints-3.12.txt from the build context (the directory you
# run `singularity build` from) into the image, same as the Dockerfile's
# COPY instruction. This file must exist alongside this .def file.
%files
    constraints-3.12.txt /src/constraints-3.12.txt

%post
    set -e

    # Build-time dependencies for compiling Python (openssl-devel is
    # required, otherwise Python ends up without the ssl module and pip
    # cannot reach PyPI)
    dnf install -y \
        openssl-devel bzip2-devel libffi-devel zlib-devel xz-devel \
        ncurses-devel readline-devel sqlite-devel tk-devel gdbm-devel
    dnf clean all

    PYSHARED_PREFIX=/opt/python-shared
    mkdir -p /src

    # Compile Python with --enable-shared, required by PyInstaller (the
    # manylinux-provided Pythons under /opt/python/cpXXX-cpXXX lack a
    # shared libpython)
    curl -O https://www.python.org/ftp/python/{{ PYVER }}/Python-{{ PYVER }}.tgz
    tar xzf Python-{{ PYVER }}.tgz
    cd Python-{{ PYVER }}
    ./configure --enable-shared --prefix="${PYSHARED_PREFIX}" --with-openssl=/usr
    make -j"$(nproc)"
    make altinstall
    cd ..
    rm -rf Python-{{ PYVER }} Python-{{ PYVER }}.tgz

    # IMPORTANT: unlike Docker's ENV, Apptainer's %environment section only
    # applies when the final container is *run* (%runscript, singularity
    # run/exec) -- it is NOT in effect during %post (the build itself). So
    # the freshly-compiled Python can't find its own shared libpython here
    # unless we export this explicitly for the rest of the build.
    export LD_LIBRARY_PATH="${PYSHARED_PREFIX}/lib"

    # Virtual environment + treecript + pyinstaller, same as the Dockerfile
    "${PYSHARED_PREFIX}/bin/python3.13" -m venv /opt/venv
    /opt/venv/bin/pip install --upgrade pip wheel
    /opt/venv/bin/pip install -c /src/constraints-3.12.txt \
        "treecript[analytics,docker] @ git+{{ TREECRIPT_GIT_URL }}@{{ TREECRIPT_REF }}"
    /opt/venv/bin/pip install pyinstaller

%environment
    export LD_LIBRARY_PATH=/opt/python-shared/lib
    export PATH=/opt/venv/bin:$PATH

# Equivalent to the Dockerfile's CMD: this is what runs by default when
# the resulting .sif is executed with `singularity run`.
%runscript
    exec /opt/venv/bin/pyinstaller -F -n execution-metrics-collector \
        /opt/venv/bin/execution-metrics-collector