License generation script for build_aar.py.

tools_webrtc/libs/generate_licenses.py

-#!/usr/bin/python
+#!/usr/bin/env python
 
 #  Copyright 2016 The WebRTC project authors. All Rights Reserved.
 #
 #  Use of this source code is governed by a BSD-style license
 #  that can be found in the LICENSE file in the root of the source
 #  tree. An additional intellectual property rights grant can be found
 #  in the file PATENTS.  All contributing project authors may
 #  be found in the AUTHORS file in the root of the source tree.
 
-"""Generates license HTML for a prebuilt version of WebRTC for iOS."""
+"""Generates license markdown for a prebuilt version of WebRTC."""
 
 import sys
 
 import argparse
 import cgi
+import json
+import logging
 import os
 import re
-import textwrap
 import subprocess
 
 
 LIB_TO_LICENSES_DICT = {
+    'android_tools': ['third_party/android_tools/LICENSE'],
     'boringssl': ['third_party/boringssl/src/LICENSE'],
     'expat': ['third_party/expat/files/COPYING'],
+    'ijar': ['third_party/ijar/LICENSE'],
     'jsoncpp': ['third_party/jsoncpp/LICENSE'],
+    'libc++': ['buildtools/third_party/libc++/trunk/LICENSE.TXT'],
+    'libc++abi': ['buildtools/third_party/libc++abi/trunk/LICENSE.TXT'],
+    'libevent': ['base/third_party/libevent/LICENSE'],
+    'libjpeg_turbo': ['third_party/libjpeg_turbo/LICENSE.md'],
+    'libsrtp': ['third_party/libsrtp/LICENSE'],
+    'libvpx': ['third_party/libvpx/source/libvpx/LICENSE'],
+    'libyuv': ['third_party/libyuv/LICENSE'],
+    'openmax_dl': ['third_party/openmax_dl/LICENSE'],
     'opus': ['third_party/opus/src/COPYING'],
     'protobuf': ['third_party/protobuf/LICENSE'],
-    'libsrtp': ['third_party/libsrtp/LICENSE'],
     'usrsctp': ['third_party/usrsctp/LICENSE'],
     'webrtc': ['webrtc/LICENSE', 'webrtc/LICENSE_THIRD_PARTY'],
-    'libvpx': ['third_party/libvpx/source/libvpx/LICENSE'],
-    'libyuv': ['third_party/libyuv/LICENSE'],
+
+    # Compile time dependencies, no license needed:
+    'yasm': [],
 }
 
 SCRIPT_DIR = os.path.dirname(os.path.realpath(sys.argv[0]))
 CHECKOUT_ROOT = os.path.abspath(os.path.join(SCRIPT_DIR, os.pardir, os.pardir))
 WEBRTC_ROOT = os.path.join(CHECKOUT_ROOT, 'webrtc')
+THIRD_PARTY_LIB_REGEX = r'^.*/third_party/([\w+]+).*$'
 
+def GetThirdPartyLibraries(buildfile_dir, target):
+  def ParseLibrary(dep):
+    """
+    Returns a regex match containing library name after third_party
 
-def GetThirdPartyLibraries(buildfile_dir, target_name):
-  def ExtractLibName(string_list):
-    # Sample input:
-    # ["   //third_party/usrsctp:usrsctp", "    //webrtc:webrtc_common"]
-    # Sample output:
-    # ["usrsctp"]
-    return re.sub(r'\(.*\)', '', string_list).strip().split(
-        os.path.sep)[-1].split(':')[0]
-  output = subprocess.check_output(
-    ["gn", "desc", buildfile_dir, target_name, '--all']) .split(os.linesep)
-  return [ExtractLibName(x) for x in output if re.search(r'third_party', x)]
+    Input one of:
+    //a/b/third_party/libname:c
+    //a/b/third_party/libname:c(d)
+    //a/b/third_party/libname/c:d(e)
+
+    Outputs match with libname in group 1 or None if this is not a third_party
+    dependency.
+    """
+    return re.match(THIRD_PARTY_LIB_REGEX, dep)
+
+  cmd = ["gn", "desc", '--all', '--format=json', os.path.abspath(buildfile_dir),
+      target]
+  logging.debug("Running: %r", cmd)
+  output_json = subprocess.check_output(cmd)
+  logging.debug("Output: %s", output_json)
+  output = json.loads(output_json)
+
+  libraries = set()
+  for target in output.values():
+    third_party_matches = (ParseLibrary(dep) for dep in target['deps'])
+    libraries |= set(match.group(1) for match in third_party_matches if match)
+  return libraries
 
 
 class LicenseBuilder(object):
 
-  def __init__(self, buildfile_dirs, target_name):
+  def __init__(self, buildfile_dirs, targets):
     self.buildfile_dirs = buildfile_dirs
-    self.target_name = target_name
+    self.targets = targets
 
   def GenerateLicenseText(self, output_dir):
     # Get a list of third_party libs from gn. For fat libraries we must consider
     # all architectures, hence the multiple buildfile directories.
-    # The `sum` function flattens the 2d list.
-    third_party_libs = sum([GetThirdPartyLibraries(buildfile, self.target_name)
-                            for buildfile in self.buildfile_dirs], [])
+    third_party_libs = set()
+    for buildfile in self.buildfile_dirs:
+      for target in self.targets:
+        third_party_libs |= GetThirdPartyLibraries(buildfile, target)
     assert len(third_party_libs) > 0
 
-    # Generate amalgamated list of libraries. Will exit with error if a
-    # lib is unrecognized.
-    license_libs = set()
-    for static_lib in third_party_libs:
-      license_path = LIB_TO_LICENSES_DICT.get(static_lib)
-      if static_lib == 'yasm':
-        # yasm is a build-time dep only, and doesn't need a license.
-        continue
-      if license_path is None:
-        print 'Missing license path for lib: %s' % static_lib
-        return 1
-      license_libs.add(static_lib)
+    missing_licenses = third_party_libs - set(LIB_TO_LICENSES_DICT.keys())
+    if missing_licenses:

[kjellander_webrtc, 2017/09/01 08:44:52]

What does this mean? Doesn't it mean that it will fail on missing licenses since
iOS is unlikely to have android_tools show up as a dependency, right?

[sakal, 2017/09/01 11:02:30]

This exception is thrown if there are deps found in gn desc that don't have an
entry in LIB_TO_LICENSES_DICT. (We don't know where their license file is so we
can't continue.)

+      error_msg = 'Missing licenses: %s' % ', '.join(missing_licenses)
+      logging.error(error_msg)
+      raise Exception(error_msg)
 
     # Put webrtc at the front of the list.
-    license_libs = sorted(license_libs)
+    license_libs = sorted(third_party_libs)
     license_libs.insert(0, 'webrtc')
 
-    # Generate HTML.
-    output_license_file = open(os.path.join(output_dir, 'LICENSE.html'), 'w+')
-    output_license_file.write('<!DOCTYPE html>\n')
-    output_license_file.write('<html>\n<head>\n')
-    output_license_file.write('<meta charset="UTF-8">\n')
-    output_license_file.write('<title>Licenses</title>\n')
-    style_tag = textwrap.dedent('''\
-    <style>
-      body { margin: 0; font-family: sans-serif; }
-      pre { background-color: #eeeeee; padding: 1em; white-space: pre-wrap; }
-      p { margin: 1em; white-space: nowrap; }
-    </style>
-    ''')
-    output_license_file.write(style_tag)
-    output_license_file.write('</head>\n')
+    logging.info("List of licenses: %s", ', '.join(license_libs))
 
+    # Generate markdown.
+    output_license_file = open(os.path.join(output_dir, 'LICENSE.md'), 'w+')
     for license_lib in license_libs:
-      output_license_file.write('<p>%s<br/></p>\n' % license_lib)
-      output_license_file.write('<pre>\n')
+      if len(LIB_TO_LICENSES_DICT[license_lib]) == 0:
+        logging.info("Skipping compile time dependency: %s", license_lib)
+        continue # Compile time dependency
+
+      output_license_file.write('# %s\n' % license_lib)
+      output_license_file.write('```\n')
       for path in LIB_TO_LICENSES_DICT[license_lib]:
         license_path = os.path.join(CHECKOUT_ROOT, path)
         with open(license_path, 'r') as license_file:
           license_text = cgi.escape(license_file.read(), quote=True)
           output_license_file.write(license_text)
           output_license_file.write('\n')
-      output_license_file.write('</pre>\n')
+      output_license_file.write('```\n\n')
 
-    output_license_file.write('</body>\n')
-    output_license_file.write('</html>')
     output_license_file.close()
-    return 0
 
 
 def main():
-  parser = argparse.ArgumentParser(description='Generate WebRTC LICENSE.html')
-  parser.add_argument('target_name',
+  parser = argparse.ArgumentParser(description='Generate WebRTC LICENSE.md')
+  parser.add_argument('--verbose', action='store_true', default=False,
+                      help='Debug logging.')
+  parser.add_argument('--target', required=True, action='append', default=[],
                       help='Name of the GN target to generate a license for')
   parser.add_argument('output_dir',
-                      help='Directory to output LICENSE.html to.')
+                      help='Directory to output LICENSE.md to.')
   parser.add_argument('buildfile_dirs', nargs="+",
                       help='Directories containing gn generated ninja files')
   args = parser.parse_args()
-  builder = LicenseBuilder(args.buildfile_dirs, args.target_name)
-  sys.exit(builder.GenerateLicenseText(args.output_dir))
+
+  logging.basicConfig(level=logging.DEBUG if args.verbose else logging.INFO)
+
+  builder = LicenseBuilder(args.buildfile_dirs, args.target)
+  builder.GenerateLicenseText(args.output_dir)
 
 
 if __name__ == '__main__':
-  main()
+  sys.exit(main())