build.py

#!/usr/bin/python

# Copyright 2017 Google Inc.
#
# Licensed under the Apache License, Version 2.0 (the 'License');
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an 'AS IS' BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

###############################################################################
# This build script is responsible for building and running all modules in
# this project. The following commands are supported:
#
#   clean : Remove all files in the output directory. This will not remove the
#           the output directory itself to allow the output directory to be
#           a symlink.
#
#   build : Build the full project. This will build all java files found in any
#           of the src directories.
#
#   rebuild : Call the clean and the build commands. For more information on
#             CLEAN and BUILD see the above entries.
#
#   run <class path> [ arguments ... ] : Run the specified class. All arguments
#                                        after the class path will be passed to
#                                        the java class when it runs.
###############################################################################

import os
import shutil
import subprocess
import sys


# Dictionary of settings that control java source compilation
CONFIG = {
  'out' : 'bin',
  'src' : [ 'src', 'test' ],
  'libraries' : [
    'third_party/junit4-4.11.jar',
    'third_party/hamcrest-core-1.3.jar',
    'third_party/gson-2.8.1.jar'
  ],
  'separators' : {
    'nt' : ';',
    'posix' : ':'
  }
}


# CLEAN
#
# Remove all files from the build output directory.
#
def clean(config) :
  out = config['out']

  for entry in [ os.path.join(out, name) for name in os.listdir(out) ] :
    if os.path.isdir(entry) :
      shutil.rmtree(entry)
    else :
      os.remove(entry)

  print('Clean PASSED')


# BUILD
#
# Build the project defined by the config object. This will find all source
# files in the source directories, link all specified libraries, and write
# all output to the out directory.
#
def build(config) :
  libraries = config['libraries']
  out = config['out']
  separator = config['separators'][os.name]
  src = config['src']

  # Find all the java source files in the given source directories.
  # Non-java source files are ignored.
  src_files = [ ]
  for src_path in src :
    for root, dirs, files in os.walk(src_path) :
      src_files += [ os.path.join(root, file) for file in files if file.endswith('.java') ]

  # Take everything so far and construct a single command to build the project.
  command = [ ]
  command += [ 'javac' ]
  command += [ '-d', out ]
  command += [ '-cp', separator.join([ out ] + libraries) ]
  command += [ '-Xlint' ]
  command += src_files

  print('running : %s' % command)

  if subprocess.call(command) != 0:
    print('Build FAILED')
    sys.exit(1)

  print('Build PASSED')



# RUN
#
# Run a class from within the project.
#
def run(config, start_class_path, arguments):
  libraries = config['libraries']
  out = config['out']
  separator = config['separators'][os.name]

  command = [ ]
  command += [ 'java' ]
  command += [ '-cp', separator.join([ out ] + libraries) ]
  command += [ start_class_path ]
  command += arguments

  print 'Running: [',
  for x in command :
    print x,
  print ']'

  if subprocess.call(command) != 0:
    print('Run FAILED')
    sys.exit(1)

  print('Run PASSED')


# USAGE
#
# Print basic usage info.
#
def usage() :
  print('Usage: python build.py clean | build | rebuild | run | help')
  print('  clean   : Remove all files in the output directory.')
  print('            This does not remove the root of the output tree.')
  print('  build   : Build the full project. This will build all java files')
  print('            found in all of the src directories.')
  print('  rebuild : perform clean followed by build.')
  print('  run <class path> [ arguments ... ] : Run the specified class.')
  print('            All arguments after the class path will be passed to')
  print('            the java class when it runs.')
  print('  help    : Print this helpful message.')


# MAIN
def main(args) :
  if len(args) > 1 :
    command = args[1]
    if 'help' == command :
      usage()
    elif 'clean' == command :
      clean(CONFIG)
    elif 'build' == command :
      build(CONFIG)
    elif 'rebuild' == command :
      clean(CONFIG)
      build(CONFIG)
    elif 'run' == command :
      if len(args) > 2 :
        java_class = args[2]
        java_params = args[3:]
        run(CONFIG, java_class, java_params)
      else :
        print('Run command requires a java class to run.')
        usage();
    else :
      print 'Unknown command: [',
      for x in args :
        print x,
      print ']'
      usage();
  else :
    print ('No parameters provided.')
    usage()


if __name__ == '__main__':
  main(sys.argv)