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Logger Module

This section documents the logging components of the Nextmv Python SDK.

logger

Logger module that writes to stderr.

This module provides utilities for redirecting standard output to standard error and for writing log messages directly to stderr.

FUNCTION DESCRIPTION
redirect_stdout

Redirect all messages written to stdout to stderr.
reset_stdout

Reset stdout to its original value.
log

Log a message to stderr.

log 

log(message: str) -> None

Log a message to stderr.

You can import the log function directly from nextmv:

from nextmv import log
PARAMETER DESCRIPTION

message

The message to log.

TYPE: str

Examples:

>>> log("An error occurred")
An error occurred
Source code in nextmv/nextmv/logger.py 
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def log(message: str) -> None:
    """
    Log a message to stderr.

    You can import the `log` function directly from `nextmv`:

    ```python
    from nextmv import log
    ```

    Parameters
    ----------
    message : str
        The message to log.

    Examples
    --------
    >>> log("An error occurred")
    An error occurred
    """

    print(message, file=sys.stderr)

redirect_stdout 

redirect_stdout() -> None

Redirect all messages written to stdout to stderr.

You can import the redirect_stdout function directly from nextmv:

from nextmv import redirect_stdout

This function captures the current sys.stdout and replaces it with sys.stderr. When redirection is no longer needed, call reset_stdout() to restore the original stdout.

Examples:

>>> redirect_stdout()
>>> print("This will go to stderr")
>>> reset_stdout()
>>> print("This will go to stdout")
Source code in nextmv/nextmv/logger.py 
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def redirect_stdout() -> None:
    """
    Redirect all messages written to stdout to stderr.

    You can import the `redirect_stdout` function directly from `nextmv`:

    ```python
    from nextmv import redirect_stdout
    ```

    This function captures the current sys.stdout and replaces it with sys.stderr.
    When redirection is no longer needed, call `reset_stdout()` to restore the
    original stdout.

    Examples
    --------
    >>> redirect_stdout()
    >>> print("This will go to stderr")
    >>> reset_stdout()
    >>> print("This will go to stdout")
    """

    global __original_stdout, __stdout_redirected
    if __stdout_redirected:
        return
    __stdout_redirected = True

    __original_stdout = sys.stdout
    sys.stdout = sys.stderr

reset_stdout 

reset_stdout() -> None

Reset stdout to its original value.

You can import the reset_stdout function directly from nextmv:

from nextmv import reset_stdout

This function should always be called after redirect_stdout() to avoid unexpected behavior. It restores the original stdout that was captured during redirection.

Examples:

>>> redirect_stdout()
>>> print("This will go to stderr")
>>> reset_stdout()
>>> print("This will go to stdout")
Source code in nextmv/nextmv/logger.py 
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def reset_stdout() -> None:
    """
    Reset stdout to its original value.

    You can import the `reset_stdout` function directly from `nextmv`:

    ```python
    from nextmv import reset_stdout
    ```

    This function should always be called after `redirect_stdout()` to avoid
    unexpected behavior. It restores the original stdout that was captured
    during redirection.

    Examples
    --------
    >>> redirect_stdout()
    >>> print("This will go to stderr")
    >>> reset_stdout()
    >>> print("This will go to stdout")
    """
    global __original_stdout, __stdout_redirected
    if not __stdout_redirected:
        return
    __stdout_redirected = False

    if __original_stdout is None:
        sys.stdout = sys.__stdout__
        return

    sys.stdout = __original_stdout
    __original_stdout = None