Update default.nix for a python package by querying Pypi

nix-python-update.sh

#! /usr/bin/env nix-shell
#! nix-shell -i bash -p jq curl

set -o nounset
set -o errexit

d=$1

f="$1/default.nix"

pname=$(grep "^[ \t]\+pname = " "${f}" | sed 's/[ \t]\+pname = "\([^\"]\+\)";/\1/')
version=$(grep "^[ \t]\+version = " "${f}" | sed 's/[ \t]\+version = "\([^\"]\+\)";/\1/')

format=$(grep "^[ \t]\+format = " "${f}" | sed 's/[ \t]\+format = "\([^\"]\+\)";/\1/')

if [[ ${format} == "wheel" ]]; then
    echo "wheel!"

    pypi=$(curl -Ls "https://pypi.org/pypi/$pname/json" | \
               jq -r '[.info.version,  (.urls[] | select(.python_version == "py2.py3") | .digests.sha256)]  | @tsv')
else
    pypi=$(curl -Ls "https://pypi.org/pypi/$pname/json" | \
               jq -r '[.info.version,  (.urls[] | select(.python_version == "source") | .digests.sha256)]  | @tsv')
fi

pypi_arr=(${pypi//\t/ })

version_new=${pypi_arr[0]}
sha256=${pypi_arr[1]}

echo "${pname} ${version} ${version_new}"

if [[ ${version} == ${version_new} ]]; then
    echo "No updates"
else
    echo "New sha256: ${sha256}"
    mv "${f}" "${f}.orig"
    sed "s/\([ \t]\+\)version = \"[^\"]\+\";/\1version = \"${version_new}\";/" "${f}.orig" | \
        sed "s/\([ \t]\+\)sha256 = \"\([^\"]\+\)\";/\1sha256 = \"${sha256}\";/" > ${f}
fi