3 # Copyright (c) 2020 Google Inc.
5 # Licensed under the Apache License, Version 2.0 (the "License");
6 # you may not use this file except in compliance with the License.
7 # You may obtain a copy of the License at
9 # http://www.apache.org/licenses/LICENSE-2.0
11 # Unless required by applicable law or agreed to in writing, software
12 # distributed under the License is distributed on an "AS IS" BASIS,
13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 # See the License for the specific language governing permissions and
15 # limitations under the License.
26 usage = """{} emits a string to stdout or file with project version information.
28 args: <project-dir> [<input-string>] [-i <input-file>] [-o <output-file>]
30 Either <input-string> or -i <input-file> needs to be provided.
32 The tool will output the provided string or file content with the following
35 <major> - The major version point parsed from the CHANGES.md file.
36 <minor> - The minor version point parsed from the CHANGES.md file.
37 <patch> - The point version point parsed from the CHANGES.md file.
38 <flavor> - The optional dash suffix parsed from the CHANGES.md file (excluding
40 <-flavor> - The optional dash suffix parsed from the CHANGES.md file (including
42 <date> - The optional date of the release in the form YYYY-MM-DD
43 <commit> - The git commit information for the directory taken from
44 "git describe" if that succeeds, or "git rev-parse HEAD"
45 if that succeeds, or otherwise a message containing the phrase
48 -o is an optional flag for writing the output string to the given file. If
49 ommitted then the string is printed to stdout.
52 def mkdir_p(directory):
53 """Make the directory, and all its ancestors as required. Any of the
54 directories are allowed to already exist."""
57 # We're being asked to make the current directory.
61 os.makedirs(directory)
63 if e.errno == errno.EEXIST and os.path.isdir(directory):
69 def command_output(cmd, directory):
70 """Runs a command in a directory and returns its standard output stream.
72 Captures the standard error stream.
74 Raises a RuntimeError if the command fails to launch or otherwise fails.
76 p = subprocess.Popen(cmd,
78 stdout=subprocess.PIPE,
79 stderr=subprocess.PIPE)
80 (stdout, _) = p.communicate()
82 raise RuntimeError('Failed to run %s in %s' % (cmd, directory))
86 def deduce_software_version(directory):
87 """Returns a software version number parsed from the CHANGES.md file
88 in the given directory.
90 The CHANGES.md file describes most recent versions first.
93 # Match the first well-formed version-and-date line.
94 # Allow trailing whitespace in the checked-out source code has
95 # unexpected carriage returns on a linefeed-only system such as
97 pattern = re.compile(r'^#* +(\d+)\.(\d+)\.(\d+)(-\w+)? (\d\d\d\d-\d\d-\d\d)? *$')
98 changes_file = os.path.join(directory, 'CHANGES.md')
99 with open(changes_file, mode='r') as f:
100 for line in f.readlines():
101 match = pattern.match(line)
104 "major": match.group(1),
105 "minor": match.group(2),
106 "patch": match.group(3),
107 "flavor": match.group(4).lstrip("-"),
108 "-flavor": match.group(4),
109 "date": match.group(5),
111 raise Exception('No version number found in {}'.format(changes_file))
114 def describe(directory):
115 """Returns a string describing the current Git HEAD version as descriptively
118 Runs 'git describe', or alternately 'git rev-parse HEAD', in directory. If
119 successful, returns the output; otherwise returns 'unknown hash, <date>'."""
121 # decode() is needed here for Python3 compatibility. In Python2,
122 # str and bytes are the same type, but not in Python3.
123 # Popen.communicate() returns a bytes instance, which needs to be
124 # decoded into text data first in Python3. And this decode() won't
126 return command_output(['git', 'describe'], directory).rstrip().decode()
129 return command_output(
130 ['git', 'rev-parse', 'HEAD'], directory).rstrip().decode()
132 # This is the fallback case where git gives us no information,
133 # e.g. because the source tree might not be in a git tree.
134 # In this case, usually use a timestamp. However, to ensure
135 # reproducible builds, allow the builder to override the wall
136 # clock time with environment variable SOURCE_DATE_EPOCH
137 # containing a (presumably) fixed timestamp.
138 timestamp = int(os.environ.get('SOURCE_DATE_EPOCH', time.time()))
139 formatted = datetime.datetime.utcfromtimestamp(timestamp).isoformat()
140 return 'unknown hash, {}'.format(formatted)
148 if len(sys.argv) < 2:
149 raise Exception("Invalid number of arguments")
151 directory = sys.argv[1]
154 if not sys.argv[i].startswith("-"):
155 input_string = sys.argv[i]
158 while i < len(sys.argv):
162 if opt == "-i" or opt == "-o":
163 if i == len(sys.argv):
164 raise Exception("Expected path after {}".format(opt))
172 raise Exception("Unknown flag {}".format(opt))
175 "directory": directory,
176 "input_string": input_string,
177 "input_file": input_file,
178 "output_file": output_file,
185 except Exception as e:
188 print(usage.format(sys.argv[0]))
191 directory = args["directory"]
192 template = args["input_string"]
194 with open(args["input_file"], 'r') as f:
196 output_file = args["output_file"]
198 software_version = deduce_software_version(directory)
199 commit = describe(directory)
201 .replace("<major>", software_version["major"]) \
202 .replace("<minor>", software_version["minor"]) \
203 .replace("<patch>", software_version["patch"]) \
204 .replace("<flavor>", software_version["flavor"]) \
205 .replace("<-flavor>", software_version["-flavor"]) \
206 .replace("<date>", software_version["date"]) \
207 .replace("<commit>", commit)
209 if output_file is None:
212 mkdir_p(os.path.dirname(output_file))
214 if os.path.isfile(output_file):
215 with open(output_file, 'r') as f:
216 if output == f.read():
219 with open(output_file, 'w') as f:
222 if __name__ == '__main__':