シェルスクリプトのオプション解析をpythonに任せる

venv) [root@SILVIA-PC ~]# more wrapper_kafka-* |cat
::::::::::::::
wrapper_kafka-metadata-quorum.sh
::::::::::::::
#!/bin/bash

f_parse_args() {
    local _script_name
    local _tmp_vars

    _script_name=$(basename "$0")
    _tmp_vars=$(mktemp)

    SCRIPT_NAME="$_script_name" TMP_VARS="$_tmp_vars" python3 - "$@" << 'PYTHON'
import argparse, sys, shlex, os

script_name = os.environ["SCRIPT_NAME"]
parser = argparse.ArgumentParser(prog=script_name)

#-------------------------------------------------------------------------------
# 共通オプション
#-------------------------------------------------------------------------------
common_options = parser.add_argument_group("スクリプトオプション")
common_options.add_argument("-v", "--verbose", action="store_true", help="詳細モードを有効にします")
common_options.add_argument("--timeout", type=int, help="タイムアウト秒")

#-------------------------------------------------------------------------------
# KafkaCLIオプション
#-------------------------------------------------------------------------------
kafka_cmds = parser.add_subparsers(dest="subcommand", title="KafkaCLIオプション")

describe_parser = kafka_cmds.add_parser("describe", help="Kafkaの状態を表示します")
describe_parser.add_argument("--status", action="store_true", help="ステータスを表示")
describe_parser.add_argument("--replication", action="store_true", help="レプリケーション情報を表示")
describe_parser.add_argument("--human-readable", action="store_true", help="人間が読みやすい形式で表示")

#-------------------------------------------------------------------------------
# 引数解析
#-------------------------------------------------------------------------------
try:
    args = parser.parse_args()
except SystemExit:
    sys.exit(1)

#-------------------------------------------------------------------------------
# common_options 抽出
#-------------------------------------------------------------------------------
common_opts = set()
common_opts_with_val = set()

for action in common_options._group_actions:
    for opt in action.option_strings:
        if action.nargs in (None, 0) and action.const is not None:
            common_opts.add(opt)
        elif action.nargs == 0:
            common_opts.add(opt)
        else:
            common_opts_with_val.add(opt)

#-------------------------------------------------------------------------------
# ARGS 生成
#-------------------------------------------------------------------------------
orig_args = []
skip_next = False

for a in sys.argv[1:]:

    if skip_next:
        skip_next = False
        continue

    if a in common_opts:
        continue

    if a in common_opts_with_val:
        skip_next = True
        continue

    orig_args.append(a)

args.ARGS = " ".join(orig_args)

#-------------------------------------------------------------------------------
# bash 変数出力
#-------------------------------------------------------------------------------
outfile = os.environ["TMP_VARS"]

with open(outfile, "w") as f:
    for key, value in vars(args).items():

        shell_key = key.upper()

        if value is None:
            val = ""
        elif value is True:
            val = "true"
        elif value is False:
            val = "false"
        else:
            val = shlex.quote(str(value))

        f.write(f"{shell_key}={val}\n")
PYTHON

    [ $? -ne 0 ] && exit 1

    source "$_tmp_vars"
    [[ $VERBOSE == true ]] && cat "$_tmp_vars"
    rm -f "$_tmp_vars"
}

f_parse_args "$@"

exit
::::::::::::::
wrapper_kafka-topic.sh
::::::::::::::
#!/bin/bash

f_parse_args() {
    local _script_name
    local _tmp_vars

    _script_name=$(basename "$0")
    _tmp_vars=$(mktemp)

    SCRIPT_NAME="$_script_name" TMP_VARS="$_tmp_vars" python3 - "$@" << 'PYTHON'
import argparse, sys, shlex, os

script_name = os.environ["SCRIPT_NAME"]
parser = argparse.ArgumentParser(prog=script_name)

#-------------------------------------------------------------------------------
# 共通オプション
#-------------------------------------------------------------------------------
common_options = parser.add_argument_group("スクリプトオプション")
common_options.add_argument("-v", "--verbose", action="store_true", help="詳細モードを有効にします")
common_options.add_argument("--timeout", type=int, help="タイムアウト秒")

#-------------------------------------------------------------------------------
# KafkaCLIオプション
#-------------------------------------------------------------------------------
kafka = parser.add_argument_group("KafkaCLIオプション")
kafka.add_argument("--list", action="store_true", help="トピック一覧")
kafka.add_argument("--topic", help="トピック名")
kafka.add_argument("--describe", action="store_true", help="トピック詳細")

#-------------------------------------------------------------------------------
# 引数解析
#-------------------------------------------------------------------------------
try:
    args = parser.parse_args()
except SystemExit:
    sys.exit(1)

#-------------------------------------------------------------------------------
# common_options 抽出
#-------------------------------------------------------------------------------
common_opts = set()
common_opts_with_val = set()

for action in common_options._group_actions:
    for opt in action.option_strings:
        if action.nargs in (None, 0) and action.const is not None:
            common_opts.add(opt)
        elif action.nargs == 0:
            common_opts.add(opt)
        else:
            common_opts_with_val.add(opt)

#-------------------------------------------------------------------------------
# ARGS 生成
#-------------------------------------------------------------------------------
orig_args = []
skip_next = False

for a in sys.argv[1:]:

    if skip_next:
        skip_next = False
        continue

    if a in common_opts:
        continue

    if a in common_opts_with_val:
        skip_next = True
        continue

    orig_args.append(a)

args.ARGS = " ".join(orig_args)

#-------------------------------------------------------------------------------
# bash 変数出力
#-------------------------------------------------------------------------------
outfile = os.environ["TMP_VARS"]

with open(outfile, "w") as f:
    for key, value in vars(args).items():

        shell_key = key.upper()

        if value is None:
            val = ""
        elif value is True:
            val = "true"
        elif value is False:
            val = "false"
        else:
            val = shlex.quote(str(value))

        f.write(f"{shell_key}={val}\n")
PYTHON

    [ $? -ne 0 ] && exit 1

    source "$_tmp_vars"
    [[ $VERBOSE == true ]] && cat "$_tmp_vars"
    rm -f "$_tmp_vars"
}

f_parse_args "$@"

exit
(venv) [root@SILVIA-PC ~]#

f_process_python_output() {
    parse_args() {
        python3 - "$@" <<'EOF'
import argparse
import sys

parser = argparse.ArgumentParser(prog='hoge.sh', description="ファイル処理スクリプト", add_help=False)
parser.add_argument('--mail-file', required=True, help='対象のファイル名')

try:
    args = parser.parse_args()
except SystemExit as e:
    if e.code == 0:
        # help表示による正常終了
        print("__HELP__")
    sys.exit(e.code)
except argparse.ArgumentError as e:
    print(f"エラー: {e}", file=sys.stderr)
    sys.exit(2)

# 正常な場合だけ変数を出力
print(f'MAIL_FILE="{args.mail_file}"')
EOF
    }

    TMP_OUTPUT=$(mktemp)
    parse_args "$@" > "$TMP_OUTPUT" 2>&1
    PYTHON_EXIT_CODE=$?

    # __HELP__ が含まれていたら eval しない
    if grep -q '__HELP__' "$TMP_OUTPUT"; then
        grep -v '__HELP__' "$TMP_OUTPUT"
        rm -f "$TMP_OUTPUT"
        exit 0
    fi

    # 成功時のみ eval 実行
    if [ "$PYTHON_EXIT_CODE" -eq 0 ]; then
        eval "$(cat "$TMP_OUTPUT")"
    else
        cat "$TMP_OUTPUT"
        rm -f "$TMP_OUTPUT"
        exit "$PYTHON_EXIT_CODE"
    fi

    rm -f "$TMP_OUTPUT"
}