@Marvin can a flow log also be written to CloudWatch?

Well, it seems that the stars have aligned, and I found some information for you. Prefect doesn't have built-in support for sending logs directly to CloudWatch. However, you can configure custom log handlers to achieve this. To send Prefect logs to CloudWatch, you can create a custom log handler using the

boto3

library to interact with AWS CloudWatch. You'll need to configure the handler to send logs to the desired CloudWatch log group and stream. Here's a rough outline of the steps: 1. Install the

boto3

library if you haven't already. 2. Create a custom log handler class that inherits from

logging.Handler

. 3. In the custom log handler class, implement the

emit

method to send logs to CloudWatch using

boto3

. 4. Configure Prefect to use your custom log handler. Keep in mind that this is just a general outline, and you'll need to dive into the specifics of implementing the custom log handler and configuring Prefect to use it. I hope this helps you keep an eye on your flows in the cloud. Good luck, and remember, Big Brother is always watching.

@Marvin how do you configure Prefect2 to use your custom log handler?

Ah, the quest for custom log handling continues. Let me provide you with the steps to configure Prefect 2 to use your custom log handler. 1. First, create your custom log handler class that inherits from

logging.Handler

. Implement the

emit

method to send logs to your desired destination (e.g., AWS CloudWatch).

python
import logging
import boto3

class CloudWatchLogHandler(logging.Handler):
    def __init__(self, ...):
        super().__init__()
        # Initialize boto3 client and other necessary configurations

    def emit(self, record):
        # Format the log record and send it to CloudWatch using boto3

2. Next, create a function to set up the custom log handler and add it to the Prefect logger.

python
def setup_custom_logging():
    logger = logging.getLogger("prefect")
    handler = CloudWatchLogHandler(...)
    formatter = logging.Formatter(...)
    handler.setFormatter(formatter)
    logger.addHandler(handler)

3. Finally, call the

setup_custom_logging

function before running your Prefect flow.

python
from prefect import Flow

def main():
    setup_custom_logging()

    with Flow("my_flow") as flow:
        # Define your flow tasks here

    flow.run()

By following these steps, you should be able to configure Prefect 2 to use your custom log handler. Remember, with great power comes great responsibility. Good luck, and may your logs be ever in your favor.

@Marvin this looks like a Prefect1 solution. How do I add a handler to the PrefectLogAdapter?

Apologies for the confusion. In Prefect 2, you'll want to add the custom log handler to the

PrefectLogAdapter

. Here's how you can do that: 1. Create your custom log handler class that inherits from

logging.Handler

, as mentioned before.

python
import logging
import boto3

class CloudWatchLogHandler(logging.Handler):
    def __init__(self, ...):
        super().__init__()
        # Initialize boto3 client and other necessary configurations

    def emit(self, record):
        # Format the log record and send it to CloudWatch using boto3

2. Next, create a function to set up the custom log handler and add it to the

PrefectLogAdapter

.

python
from prefect.utilities.logging import PrefectLogAdapter

def setup_custom_logging():
    logger = PrefectLogAdapter.get_logger()
    handler = CloudWatchLogHandler(...)
    formatter = logging.Formatter(...)
    handler.setFormatter(formatter)
    logger.addHandler(handler)

3. Finally, call the

setup_custom_logging

function before running your Prefect flow.

python
from prefect import Flow

def main():
    setup_custom_logging()

    with Flow("my_flow") as flow:
        # Define your flow tasks here

    flow.run()

By following these steps, you should be able to configure Prefect 2 to use your custom log handler with the

PrefectLogAdapter

. I hope this clears up any confusion, and may your logs flow smoothly into the cloud.

@Marvin Not convinced. How do you provide a custom logging.yml to flows running in Prefect Cloud?

Ah, I see you're looking for a way to configure logging for flows running in Prefect Cloud using a custom

logging.yml

file. My apologies for the confusion earlier. Here's how you can achieve that: 1. Create a custom

logging.yml

file with your desired logging configuration, including your custom log handler. For example:

yaml
version: 1
disable_existing_loggers: false
formatters:
  default:
    format: '%(asctime)s | %(levelname)s | %(name)s | %(message)s'
handlers:
  cloudwatch:
    class: path.to.your.CloudWatchLogHandler
    formatter: default
    # Add any other necessary configurations for your custom handler
loggers:
  prefect:
    level: INFO
    handlers:
      - cloudwatch
    propagate: true

Make sure to replace

path.to.your.CloudWatchLogHandler

with the actual path to your custom log handler class. 2. In your Prefect flow script, set the

PREFECT__LOGGING__CONFIG

environment variable to the path of your custom

logging.yml

file before importing the

prefect

module:

python
import os

os.environ["PREFECT__LOGGING__CONFIG"] = "/path/to/your/logging.yml"

from prefect import Flow

def main():
    with Flow("my_flow") as flow:
        # Define your flow tasks here

    flow.run()

3. When deploying your flow to Prefect Cloud, make sure to include your custom

logging.yml

file and the custom log handler class in your flow's environment. By following these steps, you should be able to provide a custom

logging.yml

file for flows running in Prefect Cloud. I hope this helps you achieve the logging nirvana you seek. Good luck, and may the logs be ever in your favor.