Argument parsing and package requests

breadpack.py

@@ -0,0 +1,182 @@
+#!/usr/bin/env python3
+from datetime import datetime, timezone
+from pathlib import Path
+from typing import Optional
+import argparse
+import logging
+import os
+import pwd
+
+logging.basicConfig(
+    level=logging.INFO,
+    format='%(levelname)s: %(message)s',
+)
+logger = logging.getLogger(__name__)
+
+
+def _get_username():
+    return pwd.getpwuid(os.getuid()).pw_name
+
+
+# The recfile descriptor for package requests.
+# Used if Breadpack generates the file from scratch.
+REQUEST_DESCRIPTOR = """
+%rec: PackageRequest
+%type: Date date
+%type: Processed bool
+%type: User line
+%type: Package line
+%mandatory: Package
+%allowed: Date User Processed Package Comment
+%sort: Processed Date
+%doc: Package requests made via breadpack
+""".strip()
+
+
+def request_subcommand(
+        requestsfile: Path,
+        package_name: str,
+        comment: Optional[str] = None,
+        **kwargs):
+    if not requestsfile.exists():
+        logger.warning(f'Creating file {requestsfile}')
+        with requestsfile.open('w') as f:
+            f.write(REQUEST_DESCRIPTOR)
+
+    data = {
+        'Date': datetime.now(timezone.utc).isoformat(),
+        'User': _get_username(),
+        'Processed': 'no',
+        'Package': package_name,
+    }
+    if comment:
+        data['Comment'] = comment
+
+    with requestsfile.open('a') as f:
+        f.write('\n\n' + '\n'.join([f'{k}: {v}' for k, v in data.items()]))
+
+    logger.info(f'Your request for {package_name!r} has been sent!')
+
+
+def list_subcommand(json: bool = False, upgradable: bool = False, **kwargs):
+    raise NotImplementedError
+
+
+def lint_subcommand(file, **kwargs):
+    raise NotImplementedError
+
+
+def check_subcommand(json: bool = False, save: bool = True, **kwargs):
+    raise NotImplementedError
+
+
+def lock_subcommand(**kwargs):
+    raise NotImplementedError
+
+
+def main():
+    parser = argparse.ArgumentParser(
+        description='Breadpunk.club meta-package manager'
+    )
+    parser.add_argument(
+        '--file',
+        type=Path,
+        help='Path to the breadpack.json file.',
+        default=Path('/bread/breadpack.json'),
+    )
+    parser.add_argument(
+        '--lockfile',
+        type=Path,
+        help='Path to the breadpack-lock.json file.',
+        default=Path('/bread/breadpack-lock.json'),
+    )
+    parser.add_argument(
+        '--requestsfile',
+        type=Path,
+        help='Path to the breadpack-requests.rec file.',
+        default=Path('/bread/breadpack-requests.rec'),
+    )
+
+    def nocommand(**kwargs):
+        parser.error('A subcommand is required.')
+
+    parser.set_defaults(func=nocommand)
+    subparsers = parser.add_subparsers(
+        title='subcommands',
+    )
+
+    request_parser = subparsers.add_parser(
+        'request',
+        help='Request for a new package to be installed.',
+    )
+    request_parser.add_argument(
+        'package_name',
+        help='Name of the requested package.',
+    )
+    request_parser.add_argument(
+        '-c', '--comment',
+        help='Optional comment to add notes '
+             'for the admin processing your request.',
+        default=None,
+    )
+    request_parser.set_defaults(func=request_subcommand)
+
+    list_parser = subparsers.add_parser(
+        'list',
+        help='List installed packages.',
+    )
+    list_parser.add_argument(
+        '--json',
+        help='Use JSON output.',
+        action='store_true',
+        default=False,
+    )
+    list_parser.add_argument(
+        '--upgradable',
+        help='Only list packages with available updates.',
+        action='store_true',
+        default=False,
+    )
+    list_parser.set_defaults(func=list_subcommand)
+
+    lint_parser = subparsers.add_parser(
+        'lint',
+        help='Check the syntax of the packages file and lockfile.',
+    )
+    lint_parser.set_defaults(func=lint_subcommand)
+
+    lock_parser = subparsers.add_parser(
+        'lock',
+        help='Regenerate the lockfile from scratch.',
+    )
+    lock_parser.set_defaults(func=lock_subcommand)
+
+    check_parser = subparsers.add_parser(
+        'check',
+        help='Check for available updates.',
+    )
+    check_parser.add_argument(
+        '--json',
+        help='Use JSON output.',
+        action='store_true',
+        default=False,
+    )
+    check_parser.add_argument(
+        '--save',
+        help='Update the lockfile. This is the default.',
+        action='store_true',
+        default=True,
+    )
+    check_parser.add_argument(
+        '--no-save',
+        help='Do not update the lockfile.',
+        action='store_false',
+        dest='save',
+    )
+
+    args = vars(parser.parse_args())
+    args.pop('func', nocommand)(**args)
+
+
+if __name__ == '__main__':
+    main()