Hello Prefect Community, I’m looking to automate a workflow with Prefect 2 that needs to start whenever a new file is uploaded to a Google Cloud Storage bucket. I’m not sure how to set up a trigger in Google Cloud that notifies my Prefect flow as soon as a new file is available. Ideally, this would involve some integration between Google Cloud Functions and Google Pub/Sub to detect new files and trigger the flow. Has anyone here set up something similar? Could you provide guidance or examples on how to configure the triggers and set up the flow to listen for these events? Any help or insights would be greatly appreciated! Thank you in advance!

@Marvin please look up webhooks in prefect and explain how one could event off of GCP events to POST to this prefect Webhook, creating an event, and triggering an Automation that renders that event into a Deployment's parameters do a search for each prefect proper noun

Here's a summary of information related to Prefect, webhooks, automations, deployments, and GCP events: Webhooks in Prefect: - You can create, manage, and interact with webhooks via the Prefect CLI:

prefect cloud webhook create

,

prefect cloud webhook get

,

prefect cloud webhook ls

, etc. - Webhooks in Prefect Cloud allow you to receive, observe, and react to events from other systems, transforming them into Prefect events. They consist of a unique URL and a template to translate incoming web requests to Prefect events. - The webhook endpoints have randomly generated URLs under

<https://api.prefect.cloud/hooks/>

. - More information on webhooks can be found here. Automations: - Automations in Prefect react to events in your workspace. You can create event-driven automations programmatically using a JSON payload containing the

event

and

resource

identifiers, which may include dynamic templating based on the request body. - Automations can be defined in the Prefect UI or via the Prefect Cloud API. - Some more details are available here. Deployments: - Deployments in Prefect can have parameters defined in

deployment.yaml

files. These can involve default values, which are used for flow runs based on the deployment. - It's possible to update parameters for a deployment and incorporate them into Deployment object properties, heavily tied to the Python API documentation. - Further explanations about deployments and parameters can be found here. GCP Events and Prefect: - You can utilize various GCP services such as BigQuery, Cloud Run, and Vertex AI within Prefect flows. - Using Prefect with these GCP services often requires appropriate GCP credentials loaded through a block (e.g.,

GcpCredentials.load("BLOCK-NAME-PLACEHOLDER")

). - Information regarding integration with GCP can be found here. To create an event in Prefect via a GCP event: 1. Set up a webhook in Prefect Cloud to listen for incoming GCP events (using the URL generated by Prefect). 2. Configure the GCP service (e.g., a Pub/Sub topic or a Cloud Function) to POST events to the Prefect webhook URL. 3. Define an automation in Prefect that triggers upon receiving the specific event from the GCP service. 4. Use the automation to render the event into a deployment's parameters, which can then potentially alter flow runs or cause new deployments with updated parameters. You may need to consult the Prefect documentation along with GCP documentation for the exact implementation details based on the specific GCP service and your use case.

> - Deployments in Prefect can have parameters defined in

deployment.yaml

files this should be

prefect.yaml

but basically, if you have python in GCP, you can call

emit_event

directly or otherwise you can

curl <https://api.prefect.cloud/hooks/xxx>

to get an event into prefect cloud, which you can use to trigger work by defining a trigger on your deployment like this