compile-requirements

#!/bin/bash
set -e

called_as=("$0" "$@")
pip_compile_args=(--quiet --strip-extras --no-emit-find-links --allow-unsafe)

while [[ $1 == -* ]]; do
    case "$1" in
        -H|--hashes)
            pip_compile_args+=(--generate-hashes --reuse-hashes)
            ;;
        *)
            echo "Unknown option: $1" >&2
            exit 1
            ;;
    esac
    shift
done

infile_path=${1:?Give a name of requirements*.in file as an argument}
txtfile_path=${infile_path%.in}.txt

# Change to the dir of the infile_path and use basenames for the files
cd "$(dirname "$infile_path")"
infile=${infile_path##*/}
txtfile=${txtfile_path##*/}

# If pip-compile is in PATH use it, otherwise run through pipx
pip_compile=(pip-compile)
if ! type ${pip_compile[0]} &>/dev/null; then
    pip_compile=(pipx run --spec pip-tools pip-compile)
fi

# Generate constraint files from requirements*.txt files if needed
if grep -q "^-c" "$infile"; then
    # Setup a trap for removing temporary files on exit
    tmp_files=()
    remove_tmp_files() {
        rm -f "${tmp_files[@]}"
    }
    trap remove_tmp_files EXIT

    # Generate a constraint file for each "-c *.constraints" line
    mapfile -t reqs < <(sed -nE 's/^-c *(.*).constraints.*/\1/p' < "$infile")
    for reqfile in "${reqs[@]}"; do
        tmp_files+=("$reqfile.constraints")
        grep -vE '^( *#|-e)' < "$reqfile" > "$reqfile.constraints"
    done
fi

echo -n "Generating $txtfile_path from $infile_path..."

"${pip_compile[@]}" "${pip_compile_args[@]}" "$infile"

# Post-process the output file with sed:
#
# 1. Fix the absolute path file URLs to relative paths.
# 2. Change the line having the "pip-compile" command
cwd_url="\(file://\)\?$PWD\(/\.\)\?"
sed -i "
    s%^.* @ $cwd_url%.%;
    s%$cwd_url%.%g;
    s|^\(# *\)pip-compile.*|\1${called_as[*]}|;
" "$txtfile"

echo "done"