@Marvin Is there a way for a Prefect flow to listen in on an event such as arrival of a new file in S3 bucket?

Yes, Prefect supports the ability to trigger flows based on events such as the arrival of a new file in an S3 bucket. This kind of functionality is often referred to as event-driven automation. For Prefect 3.x, the concept of using custom event triggers and automations can be employed to achieve this. Custom event triggers let you specify conditions under which a Prefect flow would be triggered. You can set such triggers to be activated when specific events occur, like file changes in external systems (e.g., an S3 bucket). More information on this can be found in the Prefect 3.x documentation. In Prefect 2.x, you might consider using the S3 integration features if you're trying to initiate tasks based on changes detected in an S3 bucket. While the documentation does not explicitly detail how to set up such a listener, creating a workflow that checks for file changes periodically and triggers subsequent actions is a typical pattern. More details on S3 integration can be found here. Remember, the ability to directly listen for S3 bucket events might also be complemented by AWS services like Lambda or SNS/SQS, which can notify your Prefect flow of such changes, effectively linking event-driven AWS capabilities with Prefect's orchestrations. It's like having your digital butler notify your robotic assistant!

@Marvin Is there an example of listening to an S3 bucket in Prefect 3x? Read the documentation but not clear what is required to achieve it.

It seems the Prefect 3.x documentation doesn't provide a direct example of listening to an S3 bucket for new file arrivals out-of-the-box. However, you can achieve this by integrating Prefect with AWS services that handle event notifications. Here's a general approach you could follow: 1. AWS S3 and Lambda/SNS/SQS: Set up S3 event notifications to trigger an AWS Lambda function, SNS topic, or an SQS queue whenever a new file is added to a bucket. 2. Prefect's Events API: Use this external trigger to call Prefect's events API or directly dispatch a Prefect flow. You'll need to set up your Prefect 3.x flow to listen for this event and start execution accordingly. The Prefect documentation describes how to associate external processes with Prefect events, allowing downstream deployments or flow runs to be triggered. 3. Custom Automations: Create custom automations or triggers within Prefect to handle these events. These might involve evaluating certain conditions based on the metadata received from the notifications, and then triggering the needed Prefect tasks or flows. For detailed steps on setting up custom event triggers and automations, you might want to check out the Prefect documentation on automations and triggers. So while Prefect doesn't directly listen to S3 itself, it can definitely integrate with the ecosystem to react to file arrivals as an event-driven workflow. It's like telling your concierge to buzz you when your pizza's delivered instead of watching out the window all day.

@Marvin Is Prefect automation capable of detecting the arrival of a new file in s3?

While Prefect Automations can handle a wide array of events within the Prefect ecosystem, detecting the direct arrival of a new file in an S3 bucket isn't something Prefect does natively by itself. However, you can set up a pipeline that achieves this using Prefect in combination with AWS services. Here's the typical pathway you would pursue: 1. AWS S3 Event: Set up an event notification on your S3 bucket that triggers whenever a new file is added. This could target an AWS Lambda function, an SNS topic, or an SQS queue. 2. Integration with Prefect: Use the triggered AWS service to send a notification or HTTP request that can invoke a Prefect Automation. This might involve using AWS Lambda to call a REST endpoint which triggers a Prefect flow or automation to start based on the incoming event. 3. Prefect Automation: Once the event is received by Prefect, you can manage it using Prefect Automations which allows you to define workflows or tasks to execute when specific conditions are met. Prefect's role, in this case, is part of a larger orchestration framework rather than being the direct listener for S3 events. For further details, you might explore Prefect 3.x's documentation on custom triggers and automations. So while Prefect doesn't have ears at the S3 door by itself, it certainly has the charm to convince someone else to keep a lookout!

you can also make an EventBridge rule where the target of the rule is your Prefect Event Webhook

@Kevin Grismore Hi Kevin. So as I understand, there must be something on AWS side such as Lambda needed to trigger the Prefect flow? I'm trying to bypass Lambda if possible.

yeah, something in AWS needs to see that the S3 event happened and hit the Prefect event webhook endpoint, preferably with the contents of the S3 event still intact. EventBridge is the least complicated way to do that

@Kevin Grismore Thank you