1#!/usr/bin/env python3
2# Copyright (C) 2023 The Android Open Source Project
3#
4# Licensed under the Apache License, Version 2.0 (the "License");
5# you may not use this file except in compliance with the License.
6# You may obtain a copy of the License at
7#
8#      http://www.apache.org/licenses/LICENSE-2.0
9#
10# Unless required by applicable law or agreed to in writing, software
11# distributed under the License is distributed on an "AS IS" BASIS,
12# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13# See the License for the specific language governing permissions and
14# limitations under the License.
15
16import argparse
17import os
18import re
19import sys
20
21def read_status_file(filepath):
22    result = {}
23    with open(filepath) as f:
24        for line in f:
25            if not line.strip():
26                continue
27            if line.endswith('\r\n'):
28                line = line.removesuffix('\r\n')
29            else:
30                line = line.removesuffix('\n')
31            var, value = line.split(' ', maxsplit=1)
32            result[var] = value
33    return result
34
35
36def cat(args):
37    status_file = read_status_file(args.file)
38    if args.variable not in status_file:
39        sys.exit(f'error: {args.variable} was not found in {args.file}')
40    print(status_file[args.variable])
41
42
43def replace(args):
44    status_file = read_status_file(args.file)
45
46    if args.var:
47        trimmed_status_file = {}
48        for var in args.var:
49            if var not in status_file:
50                sys.exit(f'error: {var} was not found in {args.file}')
51            trimmed_status_file[var] = status_file[var]
52        status_file = trimmed_status_file
53
54    pattern = re.compile("|".join([re.escape("{" + v + "}") for v in status_file.keys()]))
55
56    with open(args.input) as inf, open(args.output, 'w') as outf:
57        contents = inf.read()
58        contents = pattern.sub(lambda m: status_file[m.group(0)[1:-1]], contents)
59        outf.write(contents)
60
61
62def main():
63    parser = argparse.ArgumentParser(description = 'A utility tool for reading the bazel version file. (ctx.version_file, aka volatile-status.txt)')
64    subparsers = parser.add_subparsers(required=True)
65    cat_parser = subparsers.add_parser('cat', description = 'print the value of a single variable in the version file')
66    cat_parser.add_argument('file', help = 'path to the volatile-status.txt file')
67    cat_parser.add_argument('variable', help = 'the variable to print')
68    cat_parser.set_defaults(func=cat)
69    replace_parser = subparsers.add_parser('replace', description = 'Replace strings like {VAR_NAME} in an input file')
70    replace_parser.add_argument('file', help = 'path to the volatile-status.txt file')
71    replace_parser.add_argument('input', help = 'path to the input file with {VAR_NAME} strings')
72    replace_parser.add_argument('output', help = 'path to the output file')
73    replace_parser.add_argument('--var', nargs='*', help = 'If given, only replace these variables')
74    replace_parser.set_defaults(func=replace)
75    args = parser.parse_args()
76
77    args.func(args)
78
79
80if __name__ == '__main__':
81    try:
82        main()
83    except FileNotFoundError as e:
84        # Don't show a backtrace for FileNotFoundErrors
85        sys.exit(str(e))
86