def main()

in fairseq_cli/interactive.py [0:0]


def main(cfg: FairseqConfig):
    if isinstance(cfg, Namespace):
        cfg = convert_namespace_to_omegaconf(cfg)

    start_time = time.time()
    total_translate_time = 0

    utils.import_user_module(cfg.common)

    if cfg.interactive.buffer_size < 1:
        cfg.interactive.buffer_size = 1
    if cfg.dataset.max_tokens is None and cfg.dataset.batch_size is None:
        cfg.dataset.batch_size = 1

    assert (
        not cfg.generation.sampling or cfg.generation.nbest == cfg.generation.beam
    ), "--sampling requires --nbest to be equal to --beam"
    assert (
        not cfg.dataset.batch_size
        or cfg.dataset.batch_size <= cfg.interactive.buffer_size
    ), "--batch-size cannot be larger than --buffer-size"

    logger.info(cfg)

    # Fix seed for stochastic decoding
    if cfg.common.seed is not None and not cfg.generation.no_seed_provided:
        np.random.seed(cfg.common.seed)
        utils.set_torch_seed(cfg.common.seed)

    use_cuda = torch.cuda.is_available() and not cfg.common.cpu

    # Setup task, e.g., translation
    task = tasks.setup_task(cfg.task)

    # Load ensemble
    overrides = ast.literal_eval(cfg.common_eval.model_overrides)
    logger.info("loading model(s) from {}".format(cfg.common_eval.path))
    models, _model_args = checkpoint_utils.load_model_ensemble(
        utils.split_paths(cfg.common_eval.path),
        arg_overrides=overrides,
        task=task,
        suffix=cfg.checkpoint.checkpoint_suffix,
        strict=(cfg.checkpoint.checkpoint_shard_count == 1),
        num_shards=cfg.checkpoint.checkpoint_shard_count,
    )

    # Set dictionaries
    src_dict = task.source_dictionary
    tgt_dict = task.target_dictionary

    # Optimize ensemble for generation
    for model in models:
        if model is None:
            continue
        if cfg.common.fp16:
            model.half()
        if use_cuda and not cfg.distributed_training.pipeline_model_parallel:
            model.cuda()
        model.prepare_for_inference_(cfg)

    # Initialize generator
    generator = task.build_generator(models, cfg.generation)

    # Handle tokenization and BPE
    tokenizer = task.build_tokenizer(cfg.tokenizer)
    bpe = task.build_bpe(cfg.bpe)

    def encode_fn(x):
        if tokenizer is not None:
            x = tokenizer.encode(x)
        if bpe is not None:
            x = bpe.encode(x)
        return x

    def decode_fn(x):
        if bpe is not None:
            x = bpe.decode(x)
        if tokenizer is not None:
            x = tokenizer.decode(x)
        return x

    # Load alignment dictionary for unknown word replacement
    # (None if no unknown word replacement, empty if no path to align dictionary)
    align_dict = utils.load_align_dict(cfg.generation.replace_unk)

    max_positions = utils.resolve_max_positions(
        task.max_positions(), *[model.max_positions() for model in models]
    )

    if cfg.generation.constraints:
        logger.warning(
            "NOTE: Constrained decoding currently assumes a shared subword vocabulary."
        )

    if cfg.interactive.buffer_size > 1:
        logger.info("Sentence buffer size: %s", cfg.interactive.buffer_size)
    logger.info("NOTE: hypothesis and token scores are output in base 2")
    logger.info("Type the input sentence and press return:")
    start_id = 0
    for inputs in buffered_read(cfg.interactive.input, cfg.interactive.buffer_size):
        results = []
        for batch in make_batches(inputs, cfg, task, max_positions, encode_fn):
            bsz = batch.src_tokens.size(0)
            src_tokens = batch.src_tokens
            src_lengths = batch.src_lengths
            constraints = batch.constraints
            if use_cuda:
                src_tokens = src_tokens.cuda()
                src_lengths = src_lengths.cuda()
                if constraints is not None:
                    constraints = constraints.cuda()

            sample = {
                "net_input": {
                    "src_tokens": src_tokens,
                    "src_lengths": src_lengths,
                },
            }
            translate_start_time = time.time()
            translations = task.inference_step(
                generator, models, sample, constraints=constraints
            )
            translate_time = time.time() - translate_start_time
            total_translate_time += translate_time
            list_constraints = [[] for _ in range(bsz)]
            if cfg.generation.constraints:
                list_constraints = [unpack_constraints(c) for c in constraints]
            for i, (id, hypos) in enumerate(zip(batch.ids.tolist(), translations)):
                src_tokens_i = utils.strip_pad(src_tokens[i], tgt_dict.pad())
                constraints = list_constraints[i]
                results.append(
                    (
                        start_id + id,
                        src_tokens_i,
                        hypos,
                        {
                            "constraints": constraints,
                            "time": translate_time / len(translations),
                        },
                    )
                )

        # sort output to match input order
        for id_, src_tokens, hypos, info in sorted(results, key=lambda x: x[0]):
            src_str = ""
            if src_dict is not None:
                src_str = src_dict.string(src_tokens, cfg.common_eval.post_process)
                print("S-{}\t{}".format(id_, src_str))
                print("W-{}\t{:.3f}\tseconds".format(id_, info["time"]))
                for constraint in info["constraints"]:
                    print(
                        "C-{}\t{}".format(
                            id_,
                            tgt_dict.string(constraint, cfg.common_eval.post_process),
                        )
                    )

            # Process top predictions
            for hypo in hypos[: min(len(hypos), cfg.generation.nbest)]:
                hypo_tokens, hypo_str, alignment = utils.post_process_prediction(
                    hypo_tokens=hypo["tokens"].int().cpu(),
                    src_str=src_str,
                    alignment=hypo["alignment"],
                    align_dict=align_dict,
                    tgt_dict=tgt_dict,
                    remove_bpe=cfg.common_eval.post_process,
                    extra_symbols_to_ignore=get_symbols_to_strip_from_output(generator),
                )
                detok_hypo_str = decode_fn(hypo_str)
                score = hypo["score"] / math.log(2)  # convert to base 2
                # original hypothesis (after tokenization and BPE)
                print("H-{}\t{}\t{}".format(id_, score, hypo_str))
                # detokenized hypothesis
                print("D-{}\t{}\t{}".format(id_, score, detok_hypo_str))
                print(
                    "P-{}\t{}".format(
                        id_,
                        " ".join(
                            map(
                                lambda x: "{:.4f}".format(x),
                                # convert from base e to base 2
                                hypo["positional_scores"].div_(math.log(2)).tolist(),
                            )
                        ),
                    )
                )
                if cfg.generation.print_alignment:
                    alignment_str = " ".join(
                        ["{}-{}".format(src, tgt) for src, tgt in alignment]
                    )
                    print("A-{}\t{}".format(id_, alignment_str))

        # update running id_ counter
        start_id += len(inputs)

    logger.info(
        "Total time: {:.3f} seconds; translation time: {:.3f}".format(
            time.time() - start_time, total_translate_time
        )
    )