Esempio n. 1
0
def main(_):
    tf.logging.set_verbosity(tf.logging.INFO)

    processors = {
        "cola": classifier_utils.ColaProcessor,
        "mnli": classifier_utils.MnliProcessor,
        "mismnli": classifier_utils.MisMnliProcessor,
        "mrpc": classifier_utils.MrpcProcessor,
        "rte": classifier_utils.RteProcessor,
        "sst-2": classifier_utils.Sst2Processor,
        "sts-b": classifier_utils.StsbProcessor,
        "qqp": classifier_utils.QqpProcessor,
        "qnli": classifier_utils.QnliProcessor,
        "wnli": classifier_utils.WnliProcessor,
    }

    tokenization.validate_case_matches_checkpoint(FLAGS.do_lower_case,
                                                  FLAGS.init_checkpoint)

    if not FLAGS.do_train and not FLAGS.do_eval and not FLAGS.do_predict:
        raise ValueError(
            "At least one of `do_train`, `do_eval` or `do_predict' must be True."
        )

    if not FLAGS.albert_config_file and not FLAGS.albert_hub_module_handle:
        raise ValueError("At least one of `--albert_config_file` and "
                         "`--albert_hub_module_handle` must be set")

    if FLAGS.albert_config_file:
        albert_config = modeling.AlbertConfig.from_json_file(
            FLAGS.albert_config_file)
        if FLAGS.max_seq_length > albert_config.max_position_embeddings:
            raise ValueError(
                "Cannot use sequence length %d because the ALBERT model "
                "was only trained up to sequence length %d" %
                (FLAGS.max_seq_length, albert_config.max_position_embeddings))
    else:
        albert_config = None  # Get the config from TF-Hub.

    tf.gfile.MakeDirs(FLAGS.output_dir)

    task_name = FLAGS.task_name.lower()

    if task_name not in processors:
        raise ValueError("Task not found: %s" % (task_name))

    processor = processors[task_name](
        use_spm=True if FLAGS.spm_model_file else False,
        do_lower_case=FLAGS.do_lower_case)

    label_list = processor.get_labels()

    tokenizer = fine_tuning_utils.create_vocab(
        vocab_file=FLAGS.vocab_file,
        do_lower_case=FLAGS.do_lower_case,
        spm_model_file=FLAGS.spm_model_file,
        hub_module=FLAGS.albert_hub_module_handle)

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

    is_per_host = contrib_tpu.InputPipelineConfig.PER_HOST_V2
    if FLAGS.do_train:
        iterations_per_loop = int(
            min(FLAGS.iterations_per_loop, FLAGS.save_checkpoints_steps))
    else:
        iterations_per_loop = FLAGS.iterations_per_loop
    run_config = contrib_tpu.RunConfig(
        cluster=tpu_cluster_resolver,
        master=FLAGS.master,
        model_dir=FLAGS.output_dir,
        save_checkpoints_steps=int(FLAGS.save_checkpoints_steps),
        keep_checkpoint_max=0,
        tpu_config=contrib_tpu.TPUConfig(
            iterations_per_loop=iterations_per_loop,
            num_shards=FLAGS.num_tpu_cores,
            per_host_input_for_training=is_per_host))

    train_examples = None
    if FLAGS.do_train:
        train_examples = processor.get_train_examples(FLAGS.data_dir)
    model_fn = classifier_utils.model_fn_builder(
        albert_config=albert_config,
        num_labels=len(label_list),
        init_checkpoint=FLAGS.init_checkpoint,
        learning_rate=FLAGS.learning_rate,
        num_train_steps=FLAGS.train_step,
        num_warmup_steps=FLAGS.warmup_step,
        use_tpu=FLAGS.use_tpu,
        use_one_hot_embeddings=FLAGS.use_tpu,
        task_name=task_name,
        hub_module=FLAGS.albert_hub_module_handle,
        optimizer=FLAGS.optimizer)

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

    if FLAGS.do_train:
        cached_dir = FLAGS.cached_dir
        if not cached_dir:
            cached_dir = FLAGS.output_dir
        train_file = os.path.join(cached_dir, task_name + "_train.tf_record")
        if not tf.gfile.Exists(train_file):
            classifier_utils.file_based_convert_examples_to_features(
                train_examples, label_list, FLAGS.max_seq_length, tokenizer,
                train_file, task_name)
        tf.logging.info("***** Running training *****")
        tf.logging.info("  Num examples = %d", len(train_examples))
        tf.logging.info("  Batch size = %d", FLAGS.train_batch_size)
        tf.logging.info("  Num steps = %d", FLAGS.train_step)
        train_input_fn = classifier_utils.file_based_input_fn_builder(
            input_file=train_file,
            seq_length=FLAGS.max_seq_length,
            is_training=True,
            drop_remainder=True,
            task_name=task_name,
            use_tpu=FLAGS.use_tpu,
            bsz=FLAGS.train_batch_size)
        estimator.train(input_fn=train_input_fn, max_steps=FLAGS.train_step)

    if FLAGS.do_eval:
        eval_examples = processor.get_dev_examples(FLAGS.data_dir)
        num_actual_eval_examples = len(eval_examples)
        if FLAGS.use_tpu:
            # TPU requires a fixed batch size for all batches, therefore the number
            # of examples must be a multiple of the batch size, or else examples
            # will get dropped. So we pad with fake examples which are ignored
            # later on. These do NOT count towards the metric (all tf.metrics
            # support a per-instance weight, and these get a weight of 0.0).
            while len(eval_examples) % FLAGS.eval_batch_size != 0:
                eval_examples.append(classifier_utils.PaddingInputExample())

        cached_dir = FLAGS.cached_dir
        if not cached_dir:
            cached_dir = FLAGS.output_dir
        eval_file = os.path.join(cached_dir, task_name + "_eval.tf_record")
        if not tf.gfile.Exists(eval_file):
            classifier_utils.file_based_convert_examples_to_features(
                eval_examples, label_list, FLAGS.max_seq_length, tokenizer,
                eval_file, task_name)

        tf.logging.info("***** Running evaluation *****")
        tf.logging.info("  Num examples = %d (%d actual, %d padding)",
                        len(eval_examples), num_actual_eval_examples,
                        len(eval_examples) - num_actual_eval_examples)
        tf.logging.info("  Batch size = %d", FLAGS.eval_batch_size)

        # This tells the estimator to run through the entire set.
        eval_steps = None
        # However, if running eval on the TPU, you will need to specify the
        # number of steps.
        if FLAGS.use_tpu:
            assert len(eval_examples) % FLAGS.eval_batch_size == 0
            eval_steps = int(len(eval_examples) // FLAGS.eval_batch_size)

        eval_drop_remainder = True if FLAGS.use_tpu else False
        eval_input_fn = classifier_utils.file_based_input_fn_builder(
            input_file=eval_file,
            seq_length=FLAGS.max_seq_length,
            is_training=False,
            drop_remainder=eval_drop_remainder,
            task_name=task_name,
            use_tpu=FLAGS.use_tpu,
            bsz=FLAGS.eval_batch_size)

        best_trial_info_file = os.path.join(FLAGS.output_dir, "best_trial.txt")

        def _best_trial_info():
            """Returns information about which checkpoints have been evaled so far."""
            if tf.gfile.Exists(best_trial_info_file):
                with tf.gfile.GFile(best_trial_info_file, "r") as best_info:
                    global_step, best_metric_global_step, metric_value = (
                        best_info.read().split(":"))
                    global_step = int(global_step)
                    best_metric_global_step = int(best_metric_global_step)
                    metric_value = float(metric_value)
            else:
                metric_value = -1
                best_metric_global_step = -1
                global_step = -1
            tf.logging.info(
                "Best trial info: Step: %s, Best Value Step: %s, "
                "Best Value: %s", global_step, best_metric_global_step,
                metric_value)
            return global_step, best_metric_global_step, metric_value

        def _remove_checkpoint(checkpoint_path):
            for ext in ["meta", "data-00000-of-00001", "index"]:
                src_ckpt = checkpoint_path + ".{}".format(ext)
                tf.logging.info("removing {}".format(src_ckpt))
                tf.gfile.Remove(src_ckpt)

        def _find_valid_cands(curr_step):
            filenames = tf.gfile.ListDirectory(FLAGS.output_dir)
            candidates = []
            for filename in filenames:
                if filename.endswith(".index"):
                    ckpt_name = filename[:-6]
                    idx = ckpt_name.split("-")[-1]
                    if int(idx) > curr_step:
                        candidates.append(filename)
            return candidates

        output_eval_file = os.path.join(FLAGS.output_dir, "eval_results.txt")

        if task_name == "sts-b":
            key_name = "pearson"
        elif task_name == "cola":
            key_name = "matthew_corr"
        else:
            key_name = "eval_accuracy"

        global_step, best_perf_global_step, best_perf = _best_trial_info()
        writer = tf.gfile.GFile(output_eval_file, "w")
        while global_step < FLAGS.train_step:
            steps_and_files = {}
            filenames = tf.gfile.ListDirectory(FLAGS.output_dir)
            for filename in filenames:
                if filename.endswith(".index"):
                    ckpt_name = filename[:-6]
                    cur_filename = os.path.join(FLAGS.output_dir, ckpt_name)
                    if cur_filename.split("-")[-1] == "best":
                        continue
                    gstep = int(cur_filename.split("-")[-1])
                    if gstep not in steps_and_files:
                        tf.logging.info(
                            "Add {} to eval list.".format(cur_filename))
                        steps_and_files[gstep] = cur_filename
            tf.logging.info("found {} files.".format(len(steps_and_files)))
            if not steps_and_files:
                tf.logging.info(
                    "found 0 file, global step: {}. Sleeping.".format(
                        global_step))
                time.sleep(60)
            else:
                for checkpoint in sorted(steps_and_files.items()):
                    step, checkpoint_path = checkpoint
                    if global_step >= step:
                        if (best_perf_global_step != step
                                and len(_find_valid_cands(step)) > 1):
                            _remove_checkpoint(checkpoint_path)
                        continue
                    result = estimator.evaluate(
                        input_fn=eval_input_fn,
                        steps=eval_steps,
                        checkpoint_path=checkpoint_path)
                    global_step = result["global_step"]
                    tf.logging.info("***** Eval results *****")
                    for key in sorted(result.keys()):
                        tf.logging.info("  %s = %s", key, str(result[key]))
                        writer.write("%s = %s\n" % (key, str(result[key])))
                    writer.write("best = {}\n".format(best_perf))
                    if result[key_name] > best_perf:
                        best_perf = result[key_name]
                        best_perf_global_step = global_step
                    elif len(_find_valid_cands(global_step)) > 1:
                        _remove_checkpoint(checkpoint_path)
                    writer.write("=" * 50 + "\n")
                    writer.flush()
                    with tf.gfile.GFile(best_trial_info_file,
                                        "w") as best_info:
                        best_info.write("{}:{}:{}".format(
                            global_step, best_perf_global_step, best_perf))
        writer.close()

        for ext in ["meta", "data-00000-of-00001", "index"]:
            src_ckpt = "model.ckpt-{}.{}".format(best_perf_global_step, ext)
            tgt_ckpt = "model.ckpt-best.{}".format(ext)
            tf.logging.info("saving {} to {}".format(src_ckpt, tgt_ckpt))
            tf.io.gfile.rename(os.path.join(FLAGS.output_dir, src_ckpt),
                               os.path.join(FLAGS.output_dir, tgt_ckpt),
                               overwrite=True)

    if FLAGS.do_predict:
        predict_examples = processor.get_test_examples(FLAGS.data_dir)
        num_actual_predict_examples = len(predict_examples)
        if FLAGS.use_tpu:
            # TPU requires a fixed batch size for all batches, therefore the number
            # of examples must be a multiple of the batch size, or else examples
            # will get dropped. So we pad with fake examples which are ignored
            # later on.
            while len(predict_examples) % FLAGS.predict_batch_size != 0:
                predict_examples.append(classifier_utils.PaddingInputExample())

        predict_file = os.path.join(FLAGS.output_dir, "predict.tf_record")
        classifier_utils.file_based_convert_examples_to_features(
            predict_examples, label_list, FLAGS.max_seq_length, tokenizer,
            predict_file, task_name)

        tf.logging.info("***** Running prediction*****")
        tf.logging.info("  Num examples = %d (%d actual, %d padding)",
                        len(predict_examples), num_actual_predict_examples,
                        len(predict_examples) - num_actual_predict_examples)
        tf.logging.info("  Batch size = %d", FLAGS.predict_batch_size)

        predict_drop_remainder = True if FLAGS.use_tpu else False
        predict_input_fn = classifier_utils.file_based_input_fn_builder(
            input_file=predict_file,
            seq_length=FLAGS.max_seq_length,
            is_training=False,
            drop_remainder=predict_drop_remainder,
            task_name=task_name,
            use_tpu=FLAGS.use_tpu,
            bsz=FLAGS.predict_batch_size)

        checkpoint_path = os.path.join(FLAGS.output_dir, "model.ckpt-best")
        result = estimator.predict(input_fn=predict_input_fn,
                                   checkpoint_path=checkpoint_path)

        output_predict_file = os.path.join(FLAGS.output_dir,
                                           "test_results.tsv")
        output_submit_file = os.path.join(FLAGS.output_dir,
                                          "submit_results.tsv")
        with tf.gfile.GFile(output_predict_file, "w") as pred_writer,\
            tf.gfile.GFile(output_submit_file, "w") as sub_writer:
            sub_writer.write("index" + "\t" + "prediction\n")
            num_written_lines = 0
            tf.logging.info("***** Predict results *****")
            for (i, (example, prediction)) in\
                enumerate(zip(predict_examples, result)):
                probabilities = prediction["probabilities"]
                if i >= num_actual_predict_examples:
                    break
                output_line = "\t".join(
                    str(class_probability)
                    for class_probability in probabilities) + "\n"
                pred_writer.write(output_line)

                if task_name != "sts-b":
                    actual_label = label_list[int(prediction["predictions"])]
                else:
                    actual_label = str(prediction["predictions"])
                sub_writer.write(example.guid + "\t" + actual_label + "\n")
                num_written_lines += 1
        assert num_written_lines == num_actual_predict_examples
def main(_):
    tf.logging.set_verbosity(tf.logging.INFO)

    processors = {
        "cola": classifier_utils.ColaProcessor,
        "mnli": classifier_utils.MnliProcessor,
        "mismnli": classifier_utils.MisMnliProcessor,
        "mrpc": classifier_utils.MrpcProcessor,
        "rte": classifier_utils.RteProcessor,
        "sst-2": classifier_utils.Sst2Processor,
        "sts-b": classifier_utils.StsbProcessor,
        "qqp": classifier_utils.QqpProcessor,
        "qnli": classifier_utils.QnliProcessor,
        "wnli": classifier_utils.WnliProcessor,
    }

    tokenization.validate_case_matches_checkpoint(FLAGS.do_lower_case,
                                                  FLAGS.init_checkpoint)

    if not FLAGS.albert_config_file and not FLAGS.albert_hub_module_handle:
        raise ValueError("At least one of `--albert_config_file` and "
                         "`--albert_hub_module_handle` must be set")

    if FLAGS.albert_config_file:
        albert_config = modeling.AlbertConfig.from_json_file(
            FLAGS.albert_config_file)
        if FLAGS.max_seq_length > albert_config.max_position_embeddings:
            raise ValueError(
                "Cannot use sequence length %d because the ALBERT model "
                "was only trained up to sequence length %d" %
                (FLAGS.max_seq_length, albert_config.max_position_embeddings))
    else:
        albert_config = None  # Get the config from TF-Hub.

    tf.gfile.MakeDirs(FLAGS.output_dir)

    task_name = FLAGS.task_name.lower()

    if task_name not in processors:
        raise ValueError("Task not found: %s" % (task_name))

    processor = processors[task_name](
        use_spm=True if FLAGS.spm_model_file else False,
        do_lower_case=FLAGS.do_lower_case)

    label_list = processor.get_labels()

    tokenizer = fine_tuning_utils.create_vocab(
        vocab_file=FLAGS.vocab_file,
        do_lower_case=FLAGS.do_lower_case,
        spm_model_file=FLAGS.spm_model_file,
        hub_module=FLAGS.albert_hub_module_handle)

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

    is_per_host = contrib_tpu.InputPipelineConfig.PER_HOST_V2
    iterations_per_loop = FLAGS.iterations_per_loop
    run_config = contrib_tpu.RunConfig(
        cluster=tpu_cluster_resolver,
        master=FLAGS.master,
        model_dir=FLAGS.output_dir,
        save_checkpoints_steps=int(FLAGS.save_checkpoints_steps),
        keep_checkpoint_max=0,
        tpu_config=contrib_tpu.TPUConfig(
            iterations_per_loop=iterations_per_loop,
            num_shards=FLAGS.num_tpu_cores,
            per_host_input_for_training=is_per_host))

    model_fn = classifier_utils.model_fn_builder(
        albert_config=albert_config,
        num_labels=len(label_list),
        init_checkpoint=FLAGS.init_checkpoint,
        learning_rate=FLAGS.learning_rate,
        num_train_steps=FLAGS.train_step,
        num_warmup_steps=FLAGS.warmup_step,
        use_tpu=FLAGS.use_tpu,
        use_one_hot_embeddings=FLAGS.use_tpu,
        task_name=task_name,
        hub_module=FLAGS.albert_hub_module_handle,
        optimizer=FLAGS.optimizer)

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

    # if FLAGS.do_predict:
    eval_examples = processor.get_dev_examples(FLAGS.data_dir)
    num_actual_eval_examples = len(eval_examples)
    if FLAGS.use_tpu:
        # TPU requires a fixed batch size for all batches, therefore the number
        # of examples must be a multiple of the batch size, or else examples
        # will get dropped. So we pad with fake examples which are ignored
        # later on.
        while len(eval_examples) % FLAGS.predict_batch_size != 0:
            eval_examples.append(classifier_utils.PaddingInputExample())

    error_analysis_file = os.path.join(FLAGS.output_dir,
                                       "error_analysis.tf_record")
    classifier_utils.file_based_convert_examples_to_features(
        eval_examples, label_list, FLAGS.max_seq_length, tokenizer,
        error_analysis_file, task_name)

    tf.logging.info("***** Running error analysis on dev set*****")
    tf.logging.info("  Num examples = %d (%d actual, %d padding)",
                    len(eval_examples), num_actual_eval_examples,
                    len(eval_examples) - num_actual_eval_examples)
    tf.logging.info("  Batch size = %d", FLAGS.predict_batch_size)

    error_analysis_drop_remainder = True if FLAGS.use_tpu else False
    error_analysis_input_fn = classifier_utils.file_based_input_fn_builder(
        input_file=error_analysis_file,
        seq_length=FLAGS.max_seq_length,
        is_training=False,
        drop_remainder=error_analysis_drop_remainder,
        task_name=task_name,
        use_tpu=FLAGS.use_tpu,
        bsz=FLAGS.predict_batch_size)

    checkpoint_path = os.path.join(FLAGS.output_dir, "model.ckpt-best")
    result = estimator.predict(input_fn=error_analysis_input_fn,
                               checkpoint_path=checkpoint_path)

    output_error_analysis_predict_file = os.path.join(
        FLAGS.output_dir, "error_analysis_test_results.tsv")
    output_error_analysis_submit_file = os.path.join(
        FLAGS.output_dir, "error_analysis_submit_results.tsv")
    with tf.gfile.GFile(output_error_analysis_predict_file, "w") as pred_writer,\
        tf.gfile.GFile(output_error_analysis_submit_file, "w") as sub_writer:
        sub_writer.write("index" + "\t" + "text_a" + "\t" + "text_b" + "\t" +
                         "prediction" + "\t" + "label" + "\n")
        num_written_lines = 0
        tf.logging.info("***** Error analysis results *****")
        for (i, (example, prediction)) in\
            enumerate(zip(eval_examples, result)):
            probabilities = prediction["probabilities"]
            if i >= num_actual_eval_examples:
                break
            output_line = "\t".join(
                str(class_probability)
                for class_probability in probabilities) + "\n"
            pred_writer.write(output_line)

            if task_name != "sts-b":
                actual_label = label_list[int(prediction["predictions"])]
            else:
                actual_label = str(prediction["predictions"])
            sub_writer.write(example.guid + "\t" + str(example.text_a) + "\t" +
                             str(example.text_b) + "\t" + str(actual_label) +
                             "\t" + str(example.label) + "\n")
            num_written_lines += 1
    assert num_written_lines == num_actual_eval_examples
Esempio n. 3
0
def main(_):
    tf.logging.set_verbosity(tf.logging.INFO)

    processors = {
        "cola": classifier_utils.ColaProcessor,
        "mnli": classifier_utils.MnliProcessor,
        "mrpc": classifier_utils.MrpcProcessor,
        "qr_similarity": classifier_utils.QueryResourceSimilarityProcessor
    }

    if not FLAGS.do_train and not FLAGS.do_eval:
        raise ValueError(
            "At least one of `do_train` or `do_eval` must be True.")

    tf.gfile.MakeDirs(FLAGS.output_dir)
    tf.gfile.MakeDirs(FLAGS.export_dir)

    task_name = FLAGS.task_name.lower()

    if task_name not in processors:
        raise ValueError("Task not found: %s" % (task_name))

    processor = processors[task_name]()

    label_list = processor.get_labels()

    tokenizer = create_tokenizer_from_hub_module(
        FLAGS.albert_hub_module_handle)

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

    is_per_host = contrib_tpu.InputPipelineConfig.PER_HOST_V2
    run_config = contrib_tpu.RunConfig(
        cluster=tpu_cluster_resolver,
        master=FLAGS.master,
        model_dir=FLAGS.output_dir,
        save_checkpoints_steps=FLAGS.save_checkpoints_steps,
        tpu_config=contrib_tpu.TPUConfig(
            iterations_per_loop=FLAGS.iterations_per_loop,
            num_shards=FLAGS.num_tpu_cores,
            per_host_input_for_training=is_per_host))

    train_examples = None
    num_train_steps = None
    num_warmup_steps = None
    if FLAGS.do_train:
        train_examples = processor.get_train_examples(FLAGS.data_dir)
        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)

    model_fn = model_fn_builder(
        num_labels=len(label_list),
        learning_rate=FLAGS.learning_rate,
        num_train_steps=num_train_steps,
        num_warmup_steps=num_warmup_steps,
        use_tpu=FLAGS.use_tpu,
        albert_hub_module_handle=FLAGS.albert_hub_module_handle)

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

    if FLAGS.do_train:
        train_features = classifier_utils.convert_examples_to_features(
            train_examples, label_list, FLAGS.max_seq_length, tokenizer,
            task_name)
        tf.logging.info("***** Running training *****")
        tf.logging.info("  Num examples = %d", len(train_examples))
        tf.logging.info("  Batch size = %d", FLAGS.train_batch_size)
        tf.logging.info("  Num steps = %d", num_train_steps)
        train_input_fn = classifier_utils.input_fn_builder(
            features=train_features,
            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_eval:
        eval_examples = processor.get_dev_examples(FLAGS.data_dir)
        eval_features = classifier_utils.convert_examples_to_features(
            eval_examples, label_list, FLAGS.max_seq_length, tokenizer,
            task_name)

        tf.logging.info("***** Running evaluation *****")
        tf.logging.info("  Num examples = %d", len(eval_examples))
        tf.logging.info("  Batch size = %d", FLAGS.eval_batch_size)

        # This tells the estimator to run through the entire set.
        eval_steps = None
        # However, if running eval on the TPU, you will need to specify the
        # number of steps.
        if FLAGS.use_tpu:
            # Eval will be slightly WRONG on the TPU because it will truncate
            # the last batch.
            eval_steps = int(len(eval_examples) / FLAGS.eval_batch_size)

        eval_drop_remainder = True if FLAGS.use_tpu else False
        eval_input_fn = classifier_utils.input_fn_builder(
            features=eval_features,
            seq_length=FLAGS.max_seq_length,
            is_training=False,
            drop_remainder=eval_drop_remainder)

        result = estimator.evaluate(input_fn=eval_input_fn, steps=eval_steps)

        output_eval_file = os.path.join(FLAGS.output_dir, "eval_results.txt")
        with tf.gfile.GFile(output_eval_file, "w") as writer:
            tf.logging.info("***** Eval results *****")
            for key in sorted(result.keys()):
                tf.logging.info("  %s = %s", key, str(result[key]))
                writer.write("%s = %s\n" % (key, str(result[key])))

    if FLAGS.do_predict:
        predict_examples = processor.get_test_examples(FLAGS.data_dir)
        if FLAGS.use_tpu:
            # Discard batch remainder if running on TPU
            n = len(predict_examples)
            predict_examples = predict_examples[:(
                n - n % FLAGS.predict_batch_size)]

        predict_file = os.path.join(FLAGS.output_dir, "predict.tf_record")
        classifier_utils.file_based_convert_examples_to_features(
            predict_examples, label_list, FLAGS.max_seq_length, tokenizer,
            predict_file)

        tf.logging.info("***** Running prediction*****")
        tf.logging.info("  Num examples = %d", len(predict_examples))
        tf.logging.info("  Batch size = %d", FLAGS.predict_batch_size)

        predict_input_fn = classifier_utils.file_based_input_fn_builder(
            input_file=predict_file,
            seq_length=FLAGS.max_seq_length,
            is_training=False,
            drop_remainder=FLAGS.use_tpu)

        result = estimator.predict(input_fn=predict_input_fn)

        output_predict_file = os.path.join(FLAGS.output_dir,
                                           "test_results.tsv")
        with tf.gfile.GFile(output_predict_file, "w") as writer:
            tf.logging.info("***** Predict results *****")
            for prediction in result:
                probabilities = prediction["probabilities"]
                output_line = "\t".join(
                    str(class_probability)
                    for class_probability in probabilities) + "\n"
                writer.write(output_line)

    if FLAGS.do_export:
        estimator._export_to_tpu = False
        estimator.export_savedmodel(FLAGS.export_dir, serving_input_fn)
Esempio n. 4
0
def main(_):
    tf.logging.set_verbosity(tf.logging.INFO)

    processors = {"race": race_utils.RaceProcessor}

    tokenization.validate_case_matches_checkpoint(FLAGS.do_lower_case,
                                                  FLAGS.init_checkpoint)

    if not FLAGS.do_train and not FLAGS.do_eval and not FLAGS.do_predict:
        raise ValueError(
            "At least one of `do_train`, `do_eval` or `do_predict' must be True."
        )

    albert_config = modeling.AlbertConfig.from_json_file(
        FLAGS.albert_config_file)

    if FLAGS.max_seq_length > albert_config.max_position_embeddings:
        raise ValueError(
            "Cannot use sequence length %d because the ALBERT model "
            "was only trained up to sequence length %d" %
            (FLAGS.max_seq_length, albert_config.max_position_embeddings))

    tf.gfile.MakeDirs(FLAGS.output_dir)

    task_name = FLAGS.task_name.lower()

    if task_name not in processors:
        raise ValueError("Task not found: %s" % (task_name))

    processor = processors[task_name](
        use_spm=True if FLAGS.spm_model_file else False,
        do_lower_case=FLAGS.do_lower_case,
        high_only=FLAGS.high_only,
        middle_only=FLAGS.middle_only)

    label_list = processor.get_labels()

    tokenizer = fine_tuning_utils.create_vocab(
        vocab_file=FLAGS.vocab_file,
        do_lower_case=FLAGS.do_lower_case,
        spm_model_file=FLAGS.spm_model_file,
        hub_module=FLAGS.albert_hub_module_handle)

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

    is_per_host = contrib_tpu.InputPipelineConfig.PER_HOST_V2
    if FLAGS.do_train:
        iterations_per_loop = int(
            min(FLAGS.iterations_per_loop, FLAGS.save_checkpoints_steps))
    else:
        iterations_per_loop = FLAGS.iterations_per_loop
    run_config = contrib_tpu.RunConfig(
        cluster=tpu_cluster_resolver,
        master=FLAGS.master,
        model_dir=FLAGS.output_dir,
        save_checkpoints_steps=int(FLAGS.save_checkpoints_steps),
        keep_checkpoint_max=0,
        tpu_config=contrib_tpu.TPUConfig(
            iterations_per_loop=iterations_per_loop,
            num_shards=FLAGS.num_tpu_cores,
            per_host_input_for_training=is_per_host))

    train_examples = None
    if FLAGS.do_train:
        train_examples = processor.get_train_examples(FLAGS.data_dir)

    model_fn = race_utils.model_fn_builder(
        albert_config=albert_config,
        num_labels=len(label_list),
        init_checkpoint=FLAGS.init_checkpoint,
        learning_rate=FLAGS.learning_rate,
        num_train_steps=FLAGS.train_step,
        num_warmup_steps=FLAGS.warmup_step,
        use_tpu=FLAGS.use_tpu,
        use_one_hot_embeddings=FLAGS.use_tpu,
        max_seq_length=FLAGS.max_seq_length,
        dropout_prob=FLAGS.dropout_prob,
        hub_module=FLAGS.albert_hub_module_handle)

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

    if FLAGS.do_train:
        if not tf.gfile.Exists(FLAGS.train_file):
            race_utils.file_based_convert_examples_to_features(
                train_examples, label_list, FLAGS.max_seq_length, tokenizer,
                FLAGS.train_file, FLAGS.max_qa_length)
        tf.logging.info("***** Running training *****")
        tf.logging.info("  Num examples = %d", len(train_examples))
        tf.logging.info("  Batch size = %d", FLAGS.train_batch_size)
        tf.logging.info("  Num steps = %d", FLAGS.train_step)
        train_input_fn = classifier_utils.file_based_input_fn_builder(
            input_file=FLAGS.train_file,
            seq_length=FLAGS.max_seq_length,
            is_training=True,
            drop_remainder=True,
            task_name=task_name,
            use_tpu=FLAGS.use_tpu,
            bsz=FLAGS.train_batch_size,
            multiple=len(label_list))
        estimator.train(input_fn=train_input_fn, max_steps=FLAGS.train_step)

    if FLAGS.do_eval:
        eval_examples = processor.get_dev_examples(FLAGS.data_dir)
        num_actual_eval_examples = len(eval_examples)
        if FLAGS.use_tpu:
            # TPU requires a fixed batch size for all batches, therefore the number
            # of examples must be a multiple of the batch size, or else examples
            # will get dropped. So we pad with fake examples which are ignored
            # later on. These do NOT count towards the metric (all tf.metrics
            # support a per-instance weight, and these get a weight of 0.0).
            while len(eval_examples) % FLAGS.eval_batch_size != 0:
                eval_examples.append(classifier_utils.PaddingInputExample())

        if not tf.gfile.Exists(FLAGS.eval_file):
            race_utils.file_based_convert_examples_to_features(
                eval_examples, label_list, FLAGS.max_seq_length, tokenizer,
                FLAGS.eval_file, FLAGS.max_qa_length)

        tf.logging.info("***** Running evaluation *****")
        tf.logging.info("  Num examples = %d (%d actual, %d padding)",
                        len(eval_examples), num_actual_eval_examples,
                        len(eval_examples) - num_actual_eval_examples)
        tf.logging.info("  Batch size = %d", FLAGS.eval_batch_size)

        # This tells the estimator to run through the entire set.
        eval_steps = None
        # However, if running eval on the TPU, you will need to specify the
        # number of steps.
        if FLAGS.use_tpu:
            assert len(eval_examples) % FLAGS.eval_batch_size == 0
            eval_steps = int(len(eval_examples) // FLAGS.eval_batch_size)

        eval_drop_remainder = True if FLAGS.use_tpu else False
        eval_input_fn = classifier_utils.file_based_input_fn_builder(
            input_file=FLAGS.eval_file,
            seq_length=FLAGS.max_seq_length,
            is_training=False,
            drop_remainder=eval_drop_remainder,
            task_name=task_name,
            use_tpu=FLAGS.use_tpu,
            bsz=FLAGS.eval_batch_size,
            multiple=len(label_list))

        def _find_valid_cands(curr_step):
            filenames = tf.gfile.ListDirectory(FLAGS.output_dir)
            candidates = []
            for filename in filenames:
                if filename.endswith(".index"):
                    ckpt_name = filename[:-6]
                    idx = ckpt_name.split("-")[-1]
                    if idx != "best" and int(idx) > curr_step:
                        candidates.append(filename)
            return candidates

        output_eval_file = os.path.join(FLAGS.output_dir, "eval_results.txt")
        checkpoint_path = os.path.join(FLAGS.output_dir, "model.ckpt-best")
        key_name = "eval_accuracy"
        if tf.gfile.Exists(checkpoint_path + ".index"):
            result = estimator.evaluate(input_fn=eval_input_fn,
                                        steps=eval_steps,
                                        checkpoint_path=checkpoint_path)
            best_perf = result[key_name]
            global_step = result["global_step"]
        else:
            global_step = -1
            best_perf = -1
            checkpoint_path = None
        writer = tf.gfile.GFile(output_eval_file, "w")
        while global_step < FLAGS.train_step:
            steps_and_files = {}
            filenames = tf.gfile.ListDirectory(FLAGS.output_dir)
            for filename in filenames:
                if filename.endswith(".index"):
                    ckpt_name = filename[:-6]
                    cur_filename = os.path.join(FLAGS.output_dir, ckpt_name)
                    if cur_filename.split("-")[-1] == "best":
                        continue
                    gstep = int(cur_filename.split("-")[-1])
                    if gstep not in steps_and_files:
                        tf.logging.info(
                            "Add {} to eval list.".format(cur_filename))
                        steps_and_files[gstep] = cur_filename
            tf.logging.info("found {} files.".format(len(steps_and_files)))
            # steps_and_files = sorted(steps_and_files, key=lambda x: x[0])
            if not steps_and_files:
                tf.logging.info(
                    "found 0 file, global step: {}. Sleeping.".format(
                        global_step))
                time.sleep(1)
            else:
                for ele in sorted(steps_and_files.items()):
                    step, checkpoint_path = ele
                    if global_step >= step:
                        if len(_find_valid_cands(step)) > 1:
                            for ext in [
                                    "meta", "data-00000-of-00001", "index"
                            ]:
                                src_ckpt = checkpoint_path + ".{}".format(ext)
                                tf.logging.info("removing {}".format(src_ckpt))
                                tf.gfile.Remove(src_ckpt)
                        continue
                    result = estimator.evaluate(
                        input_fn=eval_input_fn,
                        steps=eval_steps,
                        checkpoint_path=checkpoint_path)
                    global_step = result["global_step"]
                    tf.logging.info("***** Eval results *****")
                    for key in sorted(result.keys()):
                        tf.logging.info("  %s = %s", key, str(result[key]))
                        writer.write("%s = %s\n" % (key, str(result[key])))
                    writer.write("best = {}\n".format(best_perf))
                    if result[key_name] > best_perf:
                        best_perf = result[key_name]
                        for ext in ["meta", "data-00000-of-00001", "index"]:
                            src_ckpt = checkpoint_path + ".{}".format(ext)
                            tgt_ckpt = checkpoint_path.rsplit(
                                "-", 1)[0] + "-best.{}".format(ext)
                            tf.logging.info("saving {} to {}".format(
                                src_ckpt, tgt_ckpt))
                            tf.gfile.Copy(src_ckpt, tgt_ckpt, overwrite=True)
                            writer.write("saved {} to {}\n".format(
                                src_ckpt, tgt_ckpt))

                    if len(_find_valid_cands(global_step)) > 1:
                        for ext in ["meta", "data-00000-of-00001", "index"]:
                            src_ckpt = checkpoint_path + ".{}".format(ext)
                            tf.logging.info("removing {}".format(src_ckpt))
                            tf.gfile.Remove(src_ckpt)
                    writer.write("=" * 50 + "\n")
        writer.close()
    if FLAGS.do_predict:
        predict_examples = processor.get_test_examples(FLAGS.data_dir)
        num_actual_predict_examples = len(predict_examples)
        if FLAGS.use_tpu:
            # TPU requires a fixed batch size for all batches, therefore the number
            # of examples must be a multiple of the batch size, or else examples
            # will get dropped. So we pad with fake examples which are ignored
            # later on.
            while len(predict_examples) % FLAGS.predict_batch_size != 0:
                predict_examples.append(classifier_utils.PaddingInputExample())
            assert len(predict_examples) % FLAGS.predict_batch_size == 0
            predict_steps = int(
                len(predict_examples) // FLAGS.predict_batch_size)

        predict_file = os.path.join(FLAGS.output_dir, "predict.tf_record")
        race_utils.file_based_convert_examples_to_features(
            predict_examples, label_list, FLAGS.max_seq_length, tokenizer,
            predict_file, FLAGS.max_qa_length)

        tf.logging.info("***** Running prediction*****")
        tf.logging.info("  Num examples = %d (%d actual, %d padding)",
                        len(predict_examples), num_actual_predict_examples,
                        len(predict_examples) - num_actual_predict_examples)
        tf.logging.info("  Batch size = %d", FLAGS.predict_batch_size)

        predict_drop_remainder = True if FLAGS.use_tpu else False
        predict_input_fn = classifier_utils.file_based_input_fn_builder(
            input_file=predict_file,
            seq_length=FLAGS.max_seq_length,
            is_training=False,
            drop_remainder=predict_drop_remainder,
            task_name=task_name,
            use_tpu=FLAGS.use_tpu,
            bsz=FLAGS.predict_batch_size,
            multiple=len(label_list))

        checkpoint_path = os.path.join(FLAGS.output_dir, "model.ckpt-best")
        result = estimator.evaluate(input_fn=predict_input_fn,
                                    steps=predict_steps,
                                    checkpoint_path=checkpoint_path)

        output_predict_file = os.path.join(FLAGS.output_dir,
                                           "predict_results.txt")
        with tf.gfile.GFile(output_predict_file, "w") as pred_writer:
            # num_written_lines = 0
            tf.logging.info("***** Predict results *****")
            pred_writer.write("***** Predict results *****\n")
            for key in sorted(result.keys()):
                tf.logging.info("  %s = %s", key, str(result[key]))
                pred_writer.write("%s = %s\n" % (key, str(result[key])))
            pred_writer.write("best = {}\n".format(best_perf))
Esempio n. 5
0
def main(_):
    tf.logging.set_verbosity(tf.logging.INFO)

    processors = {
        "sentence_pair": classifier_utils.SentencePairClassificationProcessor,
        "lcqmc_pair": classifier_utils.LCQMCPairClassificationProcessor,
        "lcqmc": classifier_utils.LCQMCPairClassificationProcessor,
        "spam": classifier_utils.SpamClassificationProcessor
    }

    tokenization.validate_case_matches_checkpoint(FLAGS.do_lower_case,
                                                  FLAGS.init_checkpoint)

    if not (FLAGS.do_train or FLAGS.do_eval or FLAGS.do_predict
            or FLAGS.do_predict_raw or FLAGS.export_dir):
        raise ValueError(
            "At least one of `do_train`, `do_eval`, `do_predict`, `do_predict_raw` or `export_dir` "
            "must be True.")

    task_name = FLAGS.task_name.lower()

    if task_name not in processors:
        raise ValueError("Task not found: %s" % (task_name))

    processor = processors[task_name]()

    label_list = processor.get_labels()

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

    if FLAGS.do_predict_raw:
        print("***** Running single prediction*****")
        texts = FLAGS.text
        # workaround: Getting duplicate text data when using FLAGS before runing the tf app
        texts = texts[0:int(len(texts) / 2)]
        print("text data: ", texts)
        # estimator.export_saved_model(FLAGS.output_dir, create_serving_input_receiver_fn(FLAGS.max_seq_length))
        from tensorflow.contrib import predictor
        import time
        start = time.process_time()
        predict_fn = predictor.from_saved_model(FLAGS.saved_model_dir)
        print("it took", time.process_time() - start, "to load model")
        start = time.process_time()
        input_ids_data, input_mask_data, segment_ids_data = [], [], []
        for i, t in enumerate(texts):
            guid = "predict_{}".format(i + 1)
            label = tokenization.convert_to_unicode("1")
            text_a = tokenization.convert_to_unicode(t)
            text_b = None
            example = classifier_utils.InputExample(guid=guid,
                                                    text_a=text_a,
                                                    text_b=text_b,
                                                    label=label)
            feature = classifier_utils.convert_single_example(
                0, example, label_list, FLAGS.max_seq_length, tokenizer)
            input_ids_data.append(feature.input_ids)
            input_mask_data.append(feature.input_mask)
            segment_ids_data.append(feature.segment_ids)

        features = collections.OrderedDict()
        features["input_ids"] = input_ids_data
        features["input_mask"] = input_mask_data
        features["segment_ids"] = segment_ids_data
        results = predict_fn(features)
        print(results)
        print("it took", time.process_time() - start, "to do prediction")
        return

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

    if FLAGS.max_seq_length > bert_config.max_position_embeddings:
        raise ValueError(
            "Cannot use sequence length %d because the BERT model "
            "was only trained up to sequence length %d" %
            (FLAGS.max_seq_length, bert_config.max_position_embeddings))

    tf.gfile.MakeDirs(FLAGS.output_dir)

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

    is_per_host = tf.contrib.tpu.InputPipelineConfig.PER_HOST_V2
    # Cloud TPU: Invalid TPU configuration, ensure ClusterResolver is passed to tpu.
    print("###tpu_cluster_resolver:", tpu_cluster_resolver)
    run_config = tf.contrib.tpu.RunConfig(
        cluster=tpu_cluster_resolver,
        master=FLAGS.master,
        model_dir=FLAGS.output_dir,
        save_checkpoints_steps=FLAGS.save_checkpoints_steps,
        tpu_config=tf.contrib.tpu.TPUConfig(
            iterations_per_loop=FLAGS.iterations_per_loop,
            num_shards=FLAGS.num_tpu_cores,
            per_host_input_for_training=is_per_host))

    train_examples = None
    num_train_steps = None
    num_warmup_steps = None
    if FLAGS.do_train:
        train_examples = processor.get_train_examples(FLAGS.data_dir)  # TODO
        print("###length of total train_examples:", len(train_examples))
        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)

    model_fn = classifier_utils.model_fn_builder(
        bert_config=bert_config,
        num_labels=len(label_list),
        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,
        use_one_hot_embeddings=FLAGS.use_tpu)

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

    if FLAGS.do_train:
        train_file = os.path.join(FLAGS.output_dir, "train.tf_record")
        train_file_exists = os.path.exists(train_file)
        print("###train_file_exists:", train_file_exists, " ;train_file:",
              train_file)
        if not train_file_exists:  # if tf_record file not exist, convert from raw text file. # TODO
            classifier_utils.file_based_convert_examples_to_features(
                train_examples, label_list, FLAGS.max_seq_length, tokenizer,
                train_file)
        tf.logging.info("***** Running training *****")
        tf.logging.info("  Num examples = %d", len(train_examples))
        tf.logging.info("  Batch size = %d", FLAGS.train_batch_size)
        tf.logging.info("  Num steps = %d", num_train_steps)
        train_input_fn = classifier_utils.file_based_input_fn_builder(
            input_file=train_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_eval:
        eval_examples = processor.get_dev_examples(FLAGS.data_dir)
        num_actual_eval_examples = len(eval_examples)
        if FLAGS.use_tpu:
            # TPU requires a fixed batch size for all batches, therefore the number
            # of examples must be a multiple of the batch size, or else examples
            # will get dropped. So we pad with fake examples which are ignored
            # later on. These do NOT count towards the metric (all tf.metrics
            # support a per-instance weight, and these get a weight of 0.0).
            while len(eval_examples) % FLAGS.eval_batch_size != 0:
                eval_examples.append(classifier_utils.PaddingInputExample())

        eval_file = os.path.join(FLAGS.output_dir, "eval.tf_record")
        classifier_utils.file_based_convert_examples_to_features(
            eval_examples, label_list, FLAGS.max_seq_length, tokenizer,
            eval_file)

        tf.logging.info("***** Running evaluation *****")
        tf.logging.info("  Num examples = %d (%d actual, %d padding)",
                        len(eval_examples), num_actual_eval_examples,
                        len(eval_examples) - num_actual_eval_examples)
        tf.logging.info("  Batch size = %d", FLAGS.eval_batch_size)

        # This tells the estimator to run through the entire set.
        eval_steps = None
        # However, if running eval on the TPU, you will need to specify the
        # number of steps.
        if FLAGS.use_tpu:
            assert len(eval_examples) % FLAGS.eval_batch_size == 0
            eval_steps = int(len(eval_examples) // FLAGS.eval_batch_size)

        eval_drop_remainder = True if FLAGS.use_tpu else False
        eval_input_fn = classifier_utils.file_based_input_fn_builder(
            input_file=eval_file,
            seq_length=FLAGS.max_seq_length,
            is_training=False,
            drop_remainder=eval_drop_remainder)

        best_trial_info_file = os.path.join(FLAGS.output_dir, "best_trial.txt")

        def _best_trial_info():
            """Returns information about which checkpoints have been evaled so far."""
            if tf.gfile.Exists(best_trial_info_file):
                with tf.gfile.GFile(best_trial_info_file, "r") as best_info:
                    global_step, best_metric_global_step, metric_value = (
                        best_info.read().split(":"))
                    global_step = int(global_step)
                    best_metric_global_step = int(best_metric_global_step)
                    metric_value = float(metric_value)
            else:
                metric_value = -1
                best_metric_global_step = -1
                global_step = -1
            tf.logging.info(
                "Best trial info: Step: %s, Best Value Step: %s, "
                "Best Value: %s", global_step, best_metric_global_step,
                metric_value)
            return global_step, best_metric_global_step, metric_value

        def _remove_checkpoint(checkpoint_path):
            for ext in ["meta", "data-00000-of-00001", "index"]:
                src_ckpt = checkpoint_path + ".{}".format(ext)
                tf.logging.info("removing {}".format(src_ckpt))
                tf.gfile.Remove(src_ckpt)

        def _find_valid_cands(curr_step):
            filenames = tf.gfile.ListDirectory(FLAGS.output_dir)
            candidates = []
            for filename in filenames:
                if filename.endswith(".index"):
                    ckpt_name = filename[:-6]
                    idx = ckpt_name.split("-")[-1]
                    if int(idx) > curr_step:
                        candidates.append(filename)
            return candidates

        output_eval_file = os.path.join(FLAGS.output_dir, "eval_results.txt")

        if task_name == "sts-b":
            key_name = "pearson"
        elif task_name == "cola":
            key_name = "matthew_corr"
        else:
            key_name = "eval_accuracy"

        global_step, best_perf_global_step, best_perf = _best_trial_info()
        writer = tf.gfile.GFile(output_eval_file, "w")
        while global_step < num_train_steps:
            steps_and_files = {}
            filenames = tf.gfile.ListDirectory(FLAGS.output_dir)
            for filename in filenames:
                if filename.endswith(".index"):
                    ckpt_name = filename[:-6]
                    cur_filename = os.path.join(FLAGS.output_dir, ckpt_name)
                    if cur_filename.split("-")[-1] == "best":
                        continue
                    gstep = int(cur_filename.split("-")[-1])
                    if gstep not in steps_and_files:
                        tf.logging.info(
                            "Add {} to eval list.".format(cur_filename))
                        steps_and_files[gstep] = cur_filename
            tf.logging.info("found {} files.".format(len(steps_and_files)))
            if not steps_and_files:
                tf.logging.info(
                    "found 0 file, global step: {}. Sleeping.".format(
                        global_step))
                time.sleep(60)
            else:
                for checkpoint in sorted(steps_and_files.items()):
                    step, checkpoint_path = checkpoint
                    if global_step >= step:
                        if (best_perf_global_step != step
                                and len(_find_valid_cands(step)) > 1):
                            _remove_checkpoint(checkpoint_path)
                        continue
                    result = estimator.evaluate(
                        input_fn=eval_input_fn,
                        steps=eval_steps,
                        checkpoint_path=checkpoint_path)
                    global_step = result["global_step"]
                    tf.logging.info("***** Eval results *****")
                    for key in sorted(result.keys()):
                        tf.logging.info("  %s = %s", key, str(result[key]))
                        writer.write("%s = %s\n" % (key, str(result[key])))
                    writer.write("best = {}\n".format(best_perf))
                    if result[key_name] > best_perf:
                        best_perf = result[key_name]
                        best_perf_global_step = global_step
                    elif len(_find_valid_cands(global_step)) > 1:
                        _remove_checkpoint(checkpoint_path)
                    writer.write("=" * 50 + "\n")
                    writer.flush()
                    with tf.gfile.GFile(best_trial_info_file,
                                        "w") as best_info:
                        best_info.write("{}:{}:{}".format(
                            global_step, best_perf_global_step, best_perf))
        writer.close()

        for ext in ["meta", "data-00000-of-00001", "index"]:
            src_ckpt = "model.ckpt-{}.{}".format(best_perf_global_step, ext)
            tgt_ckpt = "model.ckpt-best.{}".format(ext)
            tf.logging.info("saving {} to {}".format(src_ckpt, tgt_ckpt))
            tf.io.gfile.rename(os.path.join(FLAGS.output_dir, src_ckpt),
                               os.path.join(FLAGS.output_dir, tgt_ckpt),
                               overwrite=True)

    if FLAGS.do_predict:
        predict_examples = processor.get_test_examples(FLAGS.data_dir)
        num_actual_predict_examples = len(predict_examples)
        if FLAGS.use_tpu:
            # TPU requires a fixed batch size for all batches, therefore the number
            # of examples must be a multiple of the batch size, or else examples
            # will get dropped. So we pad with fake examples which are ignored
            # later on.
            while len(predict_examples) % FLAGS.predict_batch_size != 0:
                predict_examples.append(classifier_utils.PaddingInputExample())

        predict_file = os.path.join(FLAGS.output_dir, "predict.tf_record")
        classifier_utils.file_based_convert_examples_to_features(
            predict_examples, label_list, FLAGS.max_seq_length, tokenizer,
            predict_file)

        tf.logging.info("***** Running prediction*****")
        tf.logging.info("  Num examples = %d (%d actual, %d padding)",
                        len(predict_examples), num_actual_predict_examples,
                        len(predict_examples) - num_actual_predict_examples)
        tf.logging.info("  Batch size = %d", FLAGS.predict_batch_size)

        predict_drop_remainder = True if FLAGS.use_tpu else False
        predict_input_fn = classifier_utils.file_based_input_fn_builder(
            input_file=predict_file,
            seq_length=FLAGS.max_seq_length,
            is_training=False,
            drop_remainder=predict_drop_remainder)

        checkpoint_path = os.path.join(FLAGS.output_dir, "model.ckpt-best")
        result = estimator.predict(input_fn=predict_input_fn,
                                   checkpoint_path=checkpoint_path)

        output_predict_file = os.path.join(FLAGS.output_dir,
                                           "test_results.tsv")
        output_submit_file = os.path.join(FLAGS.output_dir,
                                          "submit_results.tsv")
        with tf.gfile.GFile(output_predict_file, "w") as pred_writer,\
            tf.gfile.GFile(output_submit_file, "w") as sub_writer:
            sub_writer.write("index" + "\t" + "prediction\n")
            num_written_lines = 0
            tf.logging.info("***** Predict results *****")
            for (i, (example, prediction)) in\
                enumerate(zip(predict_examples, result)):
                probabilities = prediction["probabilities"]
                if i >= num_actual_predict_examples:
                    break
                output_line = "\t".join(
                    str(class_probability)
                    for class_probability in probabilities) + "\n"
                pred_writer.write(output_line)

                if task_name != "sts-b":
                    actual_label = label_list[int(prediction["predictions"])]
                else:
                    actual_label = str(prediction["predictions"])
                sub_writer.write(example.guid + "\t" + actual_label + "\n")
                num_written_lines += 1
        assert num_written_lines == num_actual_predict_examples

    if FLAGS.export_dir:
        tf.gfile.MakeDirs(FLAGS.export_dir)
        checkpoint_path = os.path.join(FLAGS.output_dir, "model.ckpt-best")
        tf.logging.info("Starting to export model.")
        subfolder = estimator.export_saved_model(
            export_dir_base=FLAGS.export_dir,
            serving_input_receiver_fn=_serving_input_receiver_fn,
            checkpoint_path=checkpoint_path)
        tf.logging.info("Model exported to %s.", subfolder)

        # convert the exported model as tflite model
        converter = tf.lite.TFLiteConverter.from_saved_model(
            subfolder)  # path to the SavedModel directory
        tflite_model = converter.convert()

        tflite_model_file = os.path.join(FLAGS.export_dir, "model.tflite")
        with tf.gfile.GFile(tflite_model_file, "w") as writer:
            writer.write(tflite_model)
        tf.logging.info("Convert exported model to %s.", tflite_model_file)