# Logging

🤗 Transformers has a centralized logging system, so that you can setup the verbosity of the library easily.

Currently the default verbosity of the library is `WARNING`.

To change the level of verbosity, just use one of the direct setters. For instance, here is how to change the verbosity
to the INFO level.

```python
import transformers

transformers.logging.set_verbosity_info()
```

You can also use the environment variable `TRANSFORMERS_VERBOSITY` to override the default verbosity. You can set it
to one of the following: `debug`, `info`, `warning`, `error`, `critical`, `fatal`. For example:

```bash
TRANSFORMERS_VERBOSITY=error ./myprogram.py
```

Additionally, some `warnings` can be disabled by setting the environment variable
`TRANSFORMERS_NO_ADVISORY_WARNINGS` to a true value, like *1*. This will disable any warning that is logged using
`logger.warning_advice`. For example:

```bash
TRANSFORMERS_NO_ADVISORY_WARNINGS=1 ./myprogram.py
```

Here is an example of how to use the same logger as the library in your own module or script:

```python
from transformers.utils import logging

logging.set_verbosity_info()
logger = logging.get_logger("transformers")
logger.info("INFO")
logger.warning("WARN")
```

All the methods of this logging module are documented below, the main ones are
[logging.get_verbosity()](/docs/transformers/main/en/main_classes/logging#transformers.utils.logging.get_verbosity) to get the current level of verbosity in the logger and
[logging.set_verbosity()](/docs/transformers/main/en/main_classes/logging#transformers.utils.logging.set_verbosity) to set the verbosity to the level of your choice. In order (from the least
verbose to the most verbose), those levels (with their corresponding int values in parenthesis) are:

- `transformers.logging.CRITICAL` or `transformers.logging.FATAL` (int value, 50): only report the most
  critical errors.
- `transformers.logging.ERROR` (int value, 40): only report errors.
- `transformers.logging.WARNING` or `transformers.logging.WARN` (int value, 30): only reports error and
  warnings. This is the default level used by the library.
- `transformers.logging.INFO` (int value, 20): reports error, warnings and basic information.
- `transformers.logging.DEBUG` (int value, 10): report all information.

By default, `tqdm` progress bars will be displayed during model download. [logging.disable_progress_bar()](/docs/transformers/main/en/main_classes/logging#transformers.utils.logging.disable_progress_bar) and [logging.enable_progress_bar()](/docs/transformers/main/en/main_classes/logging#transformers.utils.logging.enable_progress_bar) can be used to suppress or unsuppress this behavior.

## `logging` vs `warnings`[[transformers.utils.logging.captureWarnings]]

Python has two logging systems that are often used in conjunction: `logging`, which is explained above, and `warnings`,
which allows further classification of warnings in specific buckets, e.g., `FutureWarning` for a feature or path
that has already been deprecated and `DeprecationWarning` to indicate an upcoming deprecation.

We use both in the `transformers` library. We leverage and adapt `logging`'s `captureWarnings` method to allow
management of these warning messages by the verbosity setters above.

What does that mean for developers of the library? We should respect the following heuristics:

- `warnings` should be favored for developers of the library and libraries dependent on `transformers`
- `logging` should be used for end-users of the library using it in every-day projects

See reference of the `captureWarnings` method below.

Calls the `captureWarnings` method from the logging library to enable management of the warnings emitted by the
`warnings` library.

Read more about this method here:
https://docs.python.org/3/library/logging.html#integration-with-the-warnings-module

All warnings will be logged through the `py.warnings` logger.

Careful: this method also adds a handler to this logger if it does not already have one, and updates the logging
level of that logger to the library's root logger.

## Base setters[[transformers.utils.logging.set_verbosity_error]]

Set the verbosity to the `ERROR` level.

Set the verbosity to the `WARNING` level.

Set the verbosity to the `INFO` level.

Set the verbosity to the `DEBUG` level.

## Other functions[[transformers.utils.logging.get_verbosity]]

`int`The logging level.

Return the current level for the 🤗 Transformers's root logger as an int.

🤗 Transformers has following logging levels:

- 50: `transformers.logging.CRITICAL` or `transformers.logging.FATAL`
- 40: `transformers.logging.ERROR`
- 30: `transformers.logging.WARNING` or `transformers.logging.WARN`
- 20: `transformers.logging.INFO`
- 10: `transformers.logging.DEBUG`

- **verbosity** (`int`) --
  Logging level, e.g., one of:

  - `transformers.logging.CRITICAL` or `transformers.logging.FATAL`
  - `transformers.logging.ERROR`
  - `transformers.logging.WARNING` or `transformers.logging.WARN`
  - `transformers.logging.INFO`
  - `transformers.logging.DEBUG`

Set the verbosity level for the 🤗 Transformers's root logger.

Return a logger with the specified name.

This function is not supposed to be directly accessed unless you are writing a custom transformers module.

Enable the default handler of the HuggingFace Transformers's root logger.

Disable the default handler of the HuggingFace Transformers's root logger.

Enable explicit formatting for every HuggingFace Transformers's logger. The explicit formatter is as follows:
```
    [LEVELNAME|FILENAME|LINE NUMBER] TIME >> MESSAGE
```

All handlers currently bound to the root logger are affected by this method.

Resets the formatting for HuggingFace Transformers's loggers.

All handlers currently bound to the root logger are affected by this method.

Enable tqdm progress bar.

Disable tqdm progress bar.