Update examples collection

emsdk-cache/emsdk-main/bazel/emscripten_toolchain/wasm_binary.py

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+"""Unpackages a bazel emscripten archive for use in a bazel BUILD rule.
+
+This script will take a tar archive containing the output of the emscripten
+toolchain. This file contains any output files produced by a wasm_cc_binary or a
+cc_binary built with --config=wasm. The files are extracted into the given
+output paths.
+
+The contents of the archive are expected to match the given outputs extnames.
+
+This script and its accompanying Bazel rule should allow you to extract a
+WebAssembly binary into a larger web application.
+"""
+
+import argparse
+import os
+import tarfile
+
+
+def ensure(f):
+  if not os.path.exists(f):
+    with open(f, 'w'):
+      pass
+
+
+def main():
+  parser = argparse.ArgumentParser()
+  parser.add_argument('--archive', help='The archive to extract from.')
+  parser.add_argument('--outputs', help='Comma separated list of files that should be extracted from the archive. Only the extname has to match a file in the archive.')
+  parser.add_argument('--allow_empty_outputs', help='If an output listed in --outputs does not exist, create it anyways.', action='store_true')
+  args = parser.parse_args()
+
+  args.archive = os.path.normpath(args.archive)
+  args.outputs = args.outputs.split(",")
+
+  tar = tarfile.open(args.archive)
+
+  for member in tar.getmembers():
+    extname = '.' + member.name.split('.', 1)[1]
+    for idx, output in enumerate(args.outputs):
+      if output.endswith(extname):
+        member_file = tar.extractfile(member)
+        with open(output, "wb") as output_file:
+          output_file.write(member_file.read())
+        args.outputs.pop(idx)
+        break
+
+  for output in args.outputs:
+    extname = '.' + output.split('.', 1)[1]
+    if args.allow_empty_outputs:
+      ensure(output)
+    else:
+      print("[ERROR] Archive does not contain file with extname: %s" % extname)
+
+
+if __name__ == '__main__':
+  main()