def main()

in mesh_tensorflow/bert/run_squad.py [0:0]


def main(_):
  tf.logging.set_verbosity(tf.logging.INFO)

  bert_config = bert_lib.BertConfig.from_json_file(FLAGS.bert_config_file)

  validate_flags_or_throw(bert_config)

  tf.gfile.MakeDirs(FLAGS.output_dir)

  tokenizer = tokenization.FullTokenizer(
      vocab_file=FLAGS.vocab_file, do_lower_case=FLAGS.do_lower_case)

  tpu_cluster_resolver = None
  if FLAGS.use_tpu and FLAGS.tpu_name:
    tpu_cluster_resolver = tf.distribute.cluster_resolver.TPUClusterResolver(
        FLAGS.tpu_name, zone=FLAGS.tpu_zone, project=FLAGS.gcp_project)

  run_config = tf.estimator.tpu.RunConfig(
      cluster=tpu_cluster_resolver,
      master=FLAGS.master,
      model_dir=FLAGS.output_dir,
      save_checkpoints_steps=FLAGS.save_checkpoints_steps,
      tpu_config=tf.estimator.tpu.TPUConfig(
          iterations_per_loop=FLAGS.iterations_per_loop,
          num_cores_per_replica=1,
          per_host_input_for_training=tf.estimator.tpu.InputPipelineConfig
          .BROADCAST))

  train_examples = None
  num_train_steps = None
  num_warmup_steps = None
  if FLAGS.do_train:
    train_examples = read_squad_examples(
        input_file=FLAGS.train_file, is_training=True)
    num_train_steps = int(
        len(train_examples) / FLAGS.train_batch_size * FLAGS.num_train_epochs)
    num_warmup_steps = int(num_train_steps * FLAGS.warmup_proportion)

    # Pre-shuffle the input to avoid having to make a very large shuffle
    # buffer in in the `input_fn`.
    rng = random.Random(12345)
    rng.shuffle(train_examples)

  model_fn = model_fn_builder(
      bert_config=bert_config,
      init_checkpoint=FLAGS.init_checkpoint,
      learning_rate=FLAGS.learning_rate,
      num_train_steps=num_train_steps,
      num_warmup_steps=num_warmup_steps,
      use_tpu=FLAGS.use_tpu)

  # If TPU is not available, this will fall back to normal Estimator on CPU
  # or GPU.
  estimator = tf.estimator.tpu.TPUEstimator(
      use_tpu=FLAGS.use_tpu,
      model_fn=model_fn,
      config=run_config,
      train_batch_size=FLAGS.train_batch_size,
      predict_batch_size=FLAGS.predict_batch_size)

  if FLAGS.do_train:
    # We write to a temporary file to avoid storing very large constant tensors
    # in memory.
    if FLAGS.cached_train_file:
      train_tfrecords_file = FLAGS.cached_train_file
    else:
      train_writer = FeatureWriter(
          filename=os.path.join(FLAGS.output_dir, "train.tf_record"),
          is_training=True)
      convert_examples_to_features(
          examples=train_examples,
          tokenizer=tokenizer,
          max_seq_length=FLAGS.max_seq_length,
          doc_stride=FLAGS.doc_stride,
          max_query_length=FLAGS.max_query_length,
          is_training=True,
          output_fn=train_writer.process_feature)
      train_writer.close()
      train_tfrecords_file = train_writer.filename

      tf.logging.info("***** Running training *****")
      tf.logging.info("  Num orig examples = %d", len(train_examples))
      tf.logging.info("  Num split examples = %d", train_writer.num_features)
      tf.logging.info("  Batch size = %d", FLAGS.train_batch_size)
      tf.logging.info("  Num steps = %d", num_train_steps)
    del train_examples

    train_input_fn = input_fn_builder(
        input_file=train_tfrecords_file,
        seq_length=FLAGS.max_seq_length,
        is_training=True,
        drop_remainder=True)
    estimator.train(input_fn=train_input_fn, max_steps=num_train_steps)

  if FLAGS.do_predict:
    eval_examples = read_squad_examples(
        input_file=FLAGS.predict_file, is_training=False)

    eval_writer = FeatureWriter(
        filename=os.path.join(FLAGS.output_dir, "eval.tf_record"),
        is_training=False)
    eval_features = []

    def append_feature(feature):
      eval_features.append(feature)
      eval_writer.process_feature(feature)

    convert_examples_to_features(
        examples=eval_examples,
        tokenizer=tokenizer,
        max_seq_length=FLAGS.max_seq_length,
        doc_stride=FLAGS.doc_stride,
        max_query_length=FLAGS.max_query_length,
        is_training=False,
        output_fn=append_feature)
    eval_writer.close()

    tf.logging.info("***** Running predictions *****")
    tf.logging.info("  Num orig examples = %d", len(eval_examples))
    tf.logging.info("  Num split examples = %d", len(eval_features))
    tf.logging.info("  Batch size = %d", FLAGS.predict_batch_size)

    all_results = []

    predict_input_fn = input_fn_builder(
        input_file=eval_writer.filename,
        seq_length=FLAGS.max_seq_length,
        is_training=False,
        drop_remainder=False)

    # If running eval on the TPU, you will need to specify the number of
    # steps.
    all_results = []
    for result in estimator.predict(
        predict_input_fn, yield_single_examples=True):
      if len(all_results) % 1000 == 0:
        tf.logging.info("Processing example: %d" % (len(all_results)))
      unique_id = int(result["unique_ids"])
      start_logits = [float(x) for x in result["start_logits"].flat]
      end_logits = [float(x) for x in result["end_logits"].flat]
      all_results.append(
          RawResult(
              unique_id=unique_id,
              start_logits=start_logits,
              end_logits=end_logits))

    output_prediction_file = os.path.join(FLAGS.output_dir, "predictions.json")
    output_nbest_file = os.path.join(FLAGS.output_dir, "nbest_predictions.json")
    output_null_log_odds_file = os.path.join(FLAGS.output_dir, "null_odds.json")

    write_predictions(eval_examples, eval_features, all_results,
                      FLAGS.n_best_size, FLAGS.max_answer_length,
                      FLAGS.do_lower_case, output_prediction_file,
                      output_nbest_file, output_null_log_odds_file)