sage-pip-install

#!/usr/bin/env bash
# This command is specifically for pip-installing from a local
# source directory, as opposed to from a package index via package
# name.  That is, it is for pip-installing Sage spkgs from their
# extracted upstream sources.
#
# This ensures that any previous installations of the same package
# are uninstalled first.

# Default arguments for all packages installed with `pip install`
# --ignore-installed : Force pip to re-install package even if it thinks it's
#                      already installed (for which it sometimes gets false
#                      positives for partially-installed packages).
# --verbose          : Display the output when running setup.py.
# --no-deps          : Don't install runtime dependencies from PyPI.
# --no-index         : Don't look at the package index.
#                      This also disables pip's version self-check.
# --isolated         : Don't read configuration files such as
#                      ~/.pydistutils.cfg
pip_install_flags="--ignore-installed --verbose --no-deps --no-index --isolated"

# Consume any additional pip install arguments except the last one
while [ $# -gt 1 ]; do
    pip_install_flags="$pip_install_flags $1"
    shift
done

# Last argument must be "." and will be ignored
if [ "$1" != "." ]; then
    echo >&2 "$0 requires . as final argument"
    exit 1
fi

# Find out the name of the package that we are installing
name="$(python setup.py --name)"

if [ $? -ne 0 ]; then
    echo >&2 "Error: could not determine package name"
    exit 1
fi

if [ $(echo "$name" | wc -l) -gt 1 ]; then
    name="$(echo "$name" | tail -1)"
    echo >&2 "Warning: This package has a badly-behaved setup.py which outputs"
    echo >&2 "more than the package name for 'setup.py --name'; using the last"
    echo >&2 "line as the package name: $name"
fi

# We should avoid running pip while uninstalling a package because that
# is prone to race conditions. Therefore, we use a lockfile while
# running pip. This is implemented in the Python script pip-lock.

# Keep uninstalling as long as it succeeds
while true; do
    out=$(pip-lock uninstall --disable-pip-version-check -y "$name" 2>&1)
    if [ $? -ne 0 ]; then
        break
    fi
    echo "$out"
done

# Not ideal, but this is the easiest way to check if the package
# was not installed to begin with (which pip treats as an error).
# If it wasn't, then we proceed quietly; if it was installed show the
# uninstallation output and error out.
if [[ "$out" != *"not installed" ]]; then
    echo >&2 "$out"
    exit 1
fi

# Finally actually do the installation (the "SHARED" tells pip-lock
# to apply a shared lock)
echo "Installing package $name using pip"
exec pip-lock SHARED install $pip_install_flags .