https://github.com/alexeyshockov/fingerscrossed.py
Buffer the logs and flush them only if something goes wrong
https://github.com/alexeyshockov/fingerscrossed.py
logging python structlog
Last synced: about 1 month ago
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Buffer the logs and flush them only if something goes wrong
- Host: GitHub
- URL: https://github.com/alexeyshockov/fingerscrossed.py
- Owner: alexeyshockov
- License: mit
- Created: 2025-02-13T19:29:37.000Z (3 months ago)
- Default Branch: main
- Last Pushed: 2025-02-25T17:18:45.000Z (3 months ago)
- Last Synced: 2025-03-07T13:52:36.657Z (2 months ago)
- Topics: logging, python, structlog
- Language: Python
- Homepage:
- Size: 43.9 KB
- Stars: 1
- Watchers: 1
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
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README
# Python logging, fingers crossed
[](https://pypi.org/project/fingerscrossed/)
[](https://sonarcloud.io/project/overview?id=alexeyshockov_fingerscrossed)
A custom sink for [Python standard logging](https://docs.python.org/3/library/logging.html) /
[structlog](https://github.com/hynek/structlog) / [loguru](https://github.com/delgan/loguru) to buffer the logs inside
a transaction and only write them if something goes wrong ("fingers crossed" pattern).
## Installation
```shell
pip install fingerscrossed
```
## Usage
### Python standard logging
```python
import logging
from fingerscrossed import fingers_crossed, FingersCrossedHandler
root_logger = logging.getLogger()
root_logger.addHandler(FingersCrossedHandler(logging.FileHandler("mylog.log")))
root_logger.setLevel(logging.NOTSET)
logger = logging.getLogger("my_logger")
def req_handler(n: int):
logger.debug("This is a debug message")
logger.info("This is an info message")
if n % 2 == 0:
logger.warning("This is a warning, does not trigger (flush the fingers crossed buffer)")
else:
logger.error("This is an error, flushes the fingers crossed buffer")
logger.info("Starting the requests")
for i in range(5):
with fingers_crossed():
req_handler(i)
logger.info("Finished")
```
### Structlog (via standard logging)
It's usual to use `structlog` with the standard logging module, [rendering everything using `structlog`'s
`ProcessorFormatter`](https://www.structlog.org/en/stable/standard-library.html#rendering-using-structlog-based-formatters-within-logging).
With this approach, the same handler decorator can be used:
```python
import logging
import structlog
from fingerscrossed import fingers_crossed, FingersCrossedStreamHandler
shared_processors = [
structlog.contextvars.merge_contextvars,
structlog.processors.add_log_level,
]
structlog.configure(
processors=shared_processors + [
structlog.stdlib.ProcessorFormatter.wrap_for_formatter,
],
wrapper_class=structlog.make_filtering_bound_logger(logging.DEBUG),
logger_factory=structlog.stdlib.LoggerFactory(),
)
stdlib_processors = [
structlog.stdlib.add_logger_name,
structlog.stdlib.PositionalArgumentsFormatter(),
structlog.stdlib.ExtraAdder(),
]
structlog_formatter = structlog.stdlib.ProcessorFormatter(
foreign_pre_chain=stdlib_processors + shared_processors,
processors=[
structlog.stdlib.ProcessorFormatter.remove_processors_meta,
structlog.dev.ConsoleRenderer(),
]
)
root_logger = logging.getLogger()
root_logger.addHandler(FingersCrossedStreamHandler(formatter=structlog_formatter))
root_logger.setLevel(logging.NOTSET)
logger = structlog.get_logger("my_logger")
# Same req_handler as above
```
### Structlog (directly)
When using `structlog` directly, the `FingersCrossedLoggerFactory` can be used to decorate the real logger:
```python
import logging
import structlog
import orjson
from fingerscrossed import fingers_crossed
from fingerscrossed.structlog import FingersCrossedLoggerFactory
structlog.configure(
processors=[
structlog.contextvars.merge_contextvars,
structlog.processors.add_log_level,
structlog.processors.JSONRenderer(orjson.dumps),
],
wrapper_class=structlog.make_filtering_bound_logger(logging.DEBUG),
logger_factory=FingersCrossedLoggerFactory(structlog.BytesLoggerFactory()),
)
logger = structlog.get_logger()
# Same req_handler as above
```
### Loguru
Loguru can use the same `FingersCrossedHandler` as the standard logging:
```python
import logging
from loguru import logger
from fingerscrossed import fingers_crossed, FingersCrossedHandler
logger.add(FingersCrossedHandler(logging.FileHandler("mylog.log")))
# Same req_handler as above
```
### OpenTelemetry SDK
TBD