Added basic file logger #1803

docs/source/loggers.rst

@@ -138,4 +138,10 @@ Test-tube
 ^^^^^^^^^
 
 .. autoclass:: pytorch_lightning.loggers.test_tube.TestTubeLogger
+    :noindex:
+
+FileLogger
+^^^^^^^^^^
+
+.. autoclass:: pytorch_lightning.loggers.file_logger.FileLogger
     :noindex:

pytorch_lightning/loggers/__init__.py

@@ -2,6 +2,8 @@
 
 from pytorch_lightning.loggers.base import LightningLoggerBase, LoggerCollection
 from pytorch_lightning.loggers.tensorboard import TensorBoardLogger
+from pytorch_lightning.loggers.file_logger import FileLogger
+
 
 __all__ = [
     'LightningLoggerBase',

pytorch_lightning/loggers/file_logger.py

@@ -0,0 +1,181 @@
+"""
+File logger
+-----------
+"""
+import io
+import os
+import csv
+import torch
+
+from argparse import Namespace
+from typing import Optional, Dict, Any, Union
+
+
+from pytorch_lightning import _logger as log
+from pytorch_lightning.core.saving import save_hparams_to_yaml
+from pytorch_lightning.loggers.base import LightningLoggerBase
+from pytorch_lightning.utilities.distributed import rank_zero_only
+
+
+class ExperimentWriter(object):
+    NAME_HPARAMS_FILE = 'hparams.yaml'
+    NAME_METRICS_FILE = 'metrics.csv'
+
+    def __init__(self, log_dir):
+        self.hparams = {}
+        self.metrics = []
+        self.metrics_keys = ["step"]
+
+        self.log_dir = log_dir
+        if not os.path.exists(log_dir):
+            os.makedirs(log_dir)
+
+        self.metrics_file_path = os.path.join(self.log_dir, self.NAME_METRICS_FILE)
+
+    def log_hparams(self, params):
+        self.hparams.update(params)
+
+    def log_metrics(self, metrics_dict, step=None):
+        def _handle_value(value):
+            if isinstance(value, torch.Tensor):
+                return value.item()
+            return value
+
+        if step is None:
+            step = len(self.metrics)
+
+        new_row = dict.fromkeys(self.metrics_keys)
+        new_row['step'] = step
+        for k, v in metrics_dict.items():
+            if k not in self.metrics_keys:
+                self.metrics_keys.append(k)
+            new_row[k] = _handle_value(v)
+        self.metrics.append(new_row)
+
+    def save(self):
+        hparams_file = os.path.join(self.log_dir, self.NAME_HPARAMS_FILE)
+        save_hparams_to_yaml(hparams_file, self.hparams)
+
+        if self.metrics:
+            with io.open(self.metrics_file_path, 'w', newline='') as f:
+                self.writer = csv.DictWriter(f, fieldnames=self.metrics_keys)
+                self.writer.writeheader()
+                self.writer.writerows(self.metrics)
+
+
+class FileLogger(LightningLoggerBase):
+    r"""
+    Log to local file system in yaml and CSV format. Logs are saved to
+    ``os.path.join(save_dir, name, version)``.
+
+    Example:
+        >>> from pytorch_lightning import Trainer
+        >>> from pytorch_lightning.loggers import FileLogger
+        >>> logger = FileLogger("logs", name="my_exp_name")
+        >>> trainer = Trainer(logger=logger)
+
+    Args:
+        save_dir: Save directory
+        name: Experiment name. Defaults to ``'default'``.
+        version: Experiment version. If version is not specified the logger inspects the save
+            directory for existing versions, then automatically assigns the next available version.
+    """
+
+    def __init__(self,
+                 save_dir: str,
+                 name: Optional[str] = "default",
+                 version: Optional[Union[int, str]] = None):
+
+        super().__init__()
+        self._save_dir = save_dir
+        self._name = name or ''
+        self._version = version
+        self._experiment = None
+
+    @property
+    def root_dir(self) -> str:
+        """
+        Parent directory for all checkpoint subdirectories.
+        If the experiment name parameter is ``None`` or the empty string, no experiment subdirectory is used
+        and the checkpoint will be saved in "save_dir/version_dir"
+        """
+        if self.name is None or len(self.name) == 0:
+            return self._save_dir
+        else:
+            return os.path.join(self._save_dir, self.name)
+
+    @property
+    def log_dir(self) -> str:
+        """
+        The log directory for this run. By default, it is named
+        ``'version_${self.version}'`` but it can be overridden by passing a string value
+        for the constructor's version parameter instead of ``None`` or an int.
+        """
+        # create a pseudo standard path ala test-tube
+        version = self.version if isinstance(self.version, str) else f"version_{self.version}"
+        log_dir = os.path.join(self.root_dir, version)
+        return log_dir
+
+    @property
+    def experiment(self) -> ExperimentWriter:
+        r"""
+
+        Actual ExperimentWriter object. To use ExperimentWriter features in your
+        :class:`~pytorch_lightning.core.lightning.LightningModule` do the following.
+
+        Example::
+
+            self.logger.experiment.some_experiment_writer_function()
+
+        """
+        if self._experiment is not None:
+            return self._experiment
+
+        os.makedirs(self.root_dir, exist_ok=True)
+        self._experiment = ExperimentWriter(log_dir=self.log_dir)
+        return self._experiment
+
+    @rank_zero_only
+    def log_hyperparams(self, params: Union[Dict[str, Any], Namespace]) -> None:
+        params = self._convert_params(params)
+        self.experiment.log_hparams(params)
+
+    @rank_zero_only
+    def log_metrics(self, metrics: Dict[str, float], step: Optional[int] = None) -> None:
+        self.experiment.log_metrics(metrics, step)
+
+    @rank_zero_only
+    def save(self) -> None:
+        super().save()
+        self.experiment.save()
+
+    @rank_zero_only
+    def finalize(self, status: str) -> None:
+        self.save()
+
+    @property
+    def name(self) -> str:
+        return self._name
+
+    @property
+    def version(self) -> int:
+        if self._version is None:
+            self._version = self._get_next_version()
+        return self._version
+
+    def _get_next_version(self):
+        root_dir = os.path.join(self._save_dir, self.name)
+
+        if not os.path.isdir(root_dir):
+            log.warning('Missing logger folder: %s', root_dir)
+            return 0
+
+        existing_versions = []
+        for d in os.listdir(root_dir):
+            if os.path.isdir(os.path.join(root_dir, d)) and d.startswith("version_"):
+                existing_versions.append(int(d.split("_")[1]))
+
+        if len(existing_versions) == 0:
+            return 0
+
+        return max(existing_versions) + 1

tests/loggers/test_file_logger.py

@@ -0,0 +1,85 @@
+from argparse import Namespace
+
+import pytest
+import torch
+import os
+
+from pytorch_lightning.loggers import FileLogger
+
+
+def test_file_logger_automatic_versioning(tmpdir):
+    """Verify that automatic versioning works"""
+
+    root_dir = tmpdir.mkdir("exp")
+    root_dir.mkdir("version_0")
+    root_dir.mkdir("version_1")
+
+    logger = FileLogger(save_dir=tmpdir, name="exp")
+
+    assert logger.version == 2
+
+
+def test_file_logger_manual_versioning(tmpdir):
+    """Verify that manual versioning works"""
+
+    root_dir = tmpdir.mkdir("exp")
+    root_dir.mkdir("version_0")
+    root_dir.mkdir("version_1")
+    root_dir.mkdir("version_2")
+
+    logger = FileLogger(save_dir=tmpdir, name="exp", version=1)
+
+    assert logger.version == 1
+
+
+def test_file_logger_named_version(tmpdir):
+    """Verify that manual versioning works for string versions, e.g. '2020-02-05-162402' """
+
+    exp_name = "exp"
+    tmpdir.mkdir(exp_name)
+    expected_version = "2020-02-05-162402"
+
+    logger = FileLogger(save_dir=tmpdir, name=exp_name, version=expected_version)
+    logger.log_hyperparams({"a": 1, "b": 2})
+    logger.save()
+    assert logger.version == expected_version
+    assert os.listdir(tmpdir / exp_name) == [expected_version]
+    assert os.listdir(tmpdir / exp_name / expected_version)
+
+
+@pytest.mark.parametrize("name", ['', None])
+def test_file_logger_no_name(tmpdir, name):
+    """Verify that None or empty name works"""
+    logger = FileLogger(save_dir=tmpdir, name=name)
+    logger.save()
+    assert logger.root_dir == tmpdir
+    assert os.listdir(tmpdir / 'version_0')
+
+
+@pytest.mark.parametrize("step_idx", [10, None])
+def test_file_logger_log_metrics(tmpdir, step_idx):
+    logger = FileLogger(tmpdir)
+    metrics = {
+        "float": 0.3,
+        "int": 1,
+        "FloatTensor": torch.tensor(0.1),
+        "IntTensor": torch.tensor(1)
+    }
+    logger.log_metrics(metrics, step_idx)
+    logger.save()
+
+
+def test_file_logger_log_hyperparams(tmpdir):
+    logger = FileLogger(tmpdir)
+    hparams = {
+        "float": 0.3,
+        "int": 1,
+        "string": "abc",
+        "bool": True,
+        "dict": {'a': {'b': 'c'}},
+        "list": [1, 2, 3],
+        "namespace": Namespace(foo=Namespace(bar='buzz')),
+        "layer": torch.nn.BatchNorm1d
+    }
+    logger.log_hyperparams(hparams)
+    logger.save()