Script to generate licenses for prebuilt WebRTC.

webrtc/build/ios/generate_licenses.py

Index: webrtc/build/ios/generate_licenses.py
diff --git a/webrtc/build/ios/generate_licenses.py b/webrtc/build/ios/generate_licenses.py
new file mode 100755
index 0000000000000000000000000000000000000000..62f75ade0978dd086265104f1a82f903ecdf0de3
--- /dev/null
+++ b/webrtc/build/ios/generate_licenses.py
@@ -0,0 +1,160 @@
+#!/usr/bin/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."""
+
+import sys

[kjellander_webrtc, 2016/04/27 12:58:05]

sort this among the other standard library modules below.

[tkchin_webrtc, 2016/04/27 21:43:28]

linter told me to place this above

[kjellander_webrtc, 2016/04/28 07:38:24]

hmm, that never happened to me, odd. I guess we'll go with the linter then since
I cannot explain it.

[tkchin_webrtc, 2016/04/28 22:38:10]

using gpylint maybe that makes a difference

[kjellander_webrtc, 2016/04/29 05:27:59]

I dunno, it seems this passed git cl presubmit (what the presubmit bot ran, so
it's fine).

+
+import argparse
+import cgi
+import os
+import re
+
+
+WEBRTC_LIBS = [

[kjellander_webrtc, 2016/04/27 12:58:05]

Ouch, you're signing up for painful maintenance here. I suggest you add a unit
test that ensures these actually exists (which may be tricky to write).
Otherwise this will break quickly when things are renamed/removed).
Unfortunately that also won't protect against new targets being added.

Maybe it's possible to do something with the output from ninja, like:
ninja -C out/Default -t targets rule phony
More info at https://ninja-build.org/manual.html

It seems hard to filter properly though, since you don't want them all.

[tkchin_webrtc, 2016/04/27 21:43:29]

Yes, the goal was to cause breakage if license changes.
But you are right that I don't really want to have to maintain this list.
As a crude approximation, how about I grep webrtc/ for target_name: 'foo' and if
the target exists in webrtc/ or talk/ we will assume it's a webrtc library
covered under our license?

gn actually fixes this for us I heard since it outputs dependencies.

[kjellander_webrtc, 2016/04/28 07:38:24]

That sounds great. I guess you'll get test and tools executables included in
that list too, but that's handled when you check for "lib" and ".a" later on. So
it should work as intended.

[tkchin_webrtc, 2016/04/28 22:38:10]

The tools won't actually be built since only dependencies for
rtc_sdk_framework_objc will be built.

[kjellander_webrtc, 2016/04/29 05:27:59]

Acknowledged.

+    'audio_coding_module',
+    'audio_conference_mixer',
+    'audio_decoder_interface',
+    'audio_device',
+    'audio_encoder_interface',
+    'audio_processing',
+    'audioproc_debug_proto',
+    'bitrate_controller',
+    'cng',
+    'common_audio',
+    'common_video',
+    'congestion_controller',
+    'field_trial_default',
+    'g711',
+    'g722',
+    'ilbc',
+    'isac',
+    'isac_common',
+    'jingle_peerconnection_objc',
+    'jingle_peerconnection',
+    'media_file',
+    'metrics_default',
+    'neteq',
+    'paced_sender',
+    'pcm16b',
+    'red',
+    'remote_bitrate_estimator',
+    'rent_a_codec',
+    'rtp_rtcp',
+    'system_wrappers',
+    'video_capture_module_internal_impl',
+    'video_capture_module',
+    'video_coding_utility',
+    'video_processing',
+    'video_render_module_internal_impl',
+    'video_render_module',
+    'voice_engine',
+]
+
+
+LIB_TO_LICENSES_DICT = {
+    'boringssl': ['third_party/boringssl/NOTICE'],
+    'expat': ['third_party/expat/files/COPYING'],
+    'jsoncpp': ['third_party/jsoncpp/LICENSE'],
+    'opus': ['third_party/opus/src/COPYING'],
+    'protobuf_lite': ['third_party/protobuf/COPYING.txt'],
+    'srtp': ['third_party/libsrtp/srtp/LICENSE'],
+    'usrsctplib': ['third_party/usrsctp/LICENSE'],
+    'webrtc': ['webrtc/LICENSE', 'webrtc/LICENSE_THIRD_PARTY'],
+    'vpx': ['third_party/libvpx/source/libvpx/LICENSE'],
+    'yuv': ['third_party/libyuv/LICENSE'],
+}
+
+
+def IsWebRTCLib(lib):
+  if (lib in WEBRTC_LIBS or
+      re.search('rtc_.*', lib) is not None or
+      re.search('webrtc.*', lib) is not None):
+    return True
+  return False
+
+
+def GetWebRTCPath():
+  # WebRTC path is script path down three directories.
+  path = os.path.dirname(os.path.realpath(sys.argv[0]))

[kjellander_webrtc, 2016/04/27 12:58:05]

Define a constant like checkout_root instead (see
https://chromium.googlesource.com/external/webrtc/+/master/webrtc/build/gyp_w...),
and use that to concatenate paths from the root.

[tkchin_webrtc, 2016/04/27 21:43:29]

Done.

+  i = 3
+  while i > 0:
+    path = os.path.dirname(path)
+    i -= 1
+  return path
+
+
+def GenerateLicenseText(static_lib_dir, output_dir):
+  # Get a list of libs from the files without their prefix and extension.
+  static_libs = []
+  for static_lib in os.listdir(static_lib_dir):
+    # Skip non libraries.
+    if not (static_lib.endswith('.a') and static_lib.startswith('lib')):
+      continue
+    # Extract library name.
+    static_libs.append(static_lib[3:-2])
+
+  # Generate amalgamated list of libraries. Mostly this just collapses the
+  # various WebRTC libs names into just 'webrtc'. Will exit with error if a
+  # lib is unrecognized.
+  license_libs = set()
+  for static_lib in static_libs:
+    license_lib = 'webrtc' if IsWebRTCLib(static_lib) else static_lib
+    license_path = LIB_TO_LICENSES_DICT.get(license_lib)
+    if license_path is None:
+      print 'Missing license path for lib: %s' % license_lib
+      sys.exit(1)
+    license_libs.add(license_lib)
+
+  # Put webrtc at the front of the list.
+  assert 'webrtc' in license_libs
+  license_libs.remove('webrtc')
+  license_libs = sorted(license_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><head>\n')
+  output_license_file.write('  <meta charset="UTF-8">\n')
+  style_tag = '''  <style>

[kjellander_webrtc, 2016/04/27 12:58:05]

Use textwrap.dedent instead, like
https://chromium.googlesource.com/external/webrtc/+/master/setup_links.py#321

[tkchin_webrtc, 2016/04/27 21:43:29]

Done.

+    body { margin: 0; font-family: sans-serif; }
+    pre { background-color: #eeeeee; padding: 1em; white-space: pre-wrap; }
+    li { list-style: none; }
+    p { margin: 1em; white-space: nowrap; }
+  </style>'''
+  output_license_file.write(style_tag)
+  output_license_file.write('\n  <title>Licenses</title>\n')

[kjellander_webrtc, 2016/04/27 12:58:05]

Put this leading newline in the end of the style_tag string instead.

[tkchin_webrtc, 2016/04/27 21:43:28]

Done.

+  output_license_file.write('</head>\n')
+
+  for license_lib in license_libs:
+    output_license_file.write('<p>\n%s<br/></p>\n' % license_lib)

[kjellander_webrtc, 2016/04/27 12:58:05]

newline in the beginning of the paragraph?

[tkchin_webrtc, 2016/04/27 21:43:29]

Done.

[kjellander_webrtc, 2016/04/28 07:38:24]

I meant I was surprised to see the newline at the beginning of the contents of
the paragraph. Does it even show up as anything?
I'd expect just
'<p>%s<br/></p>\n'
to be better

[tkchin_webrtc, 2016/04/28 22:38:10]

Oh, nope, removed.

+    output_license_file.write('<pre>\n')
+    for path in LIB_TO_LICENSES_DICT[license_lib]:
+      license_path = os.path.join(GetWebRTCPath(), 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('</body>\n')
+  output_license_file.write('</html>')
+  output_license_file.close()
+
+
+if __name__ == '__main__':
+  parser = argparse.ArgumentParser(description='Generate WebRTC LICENSE.html')
+  parser.add_argument('static_lib_dir',
+                      help='Directory with built static libraries.')
+  parser.add_argument('output_dir',
+                      help='Directory to output LICENSE.html to.')
+  args = parser.parse_args()
+  GenerateLicenseText(args.static_lib_dir, args.output_dir)