Bring your towel and join one of the fastest growing data communities. Welcome to our second-generation open source orchestration platform, a completely rethought approach to dataflow automation.

Prefect Community

Hi, is there a way to trigger a flow run similar to a webhook logic without using prefect cloud?
I have all of my infrastructure on Azure, and I wanted to trigger a flow run when a file is created on datalake.

hi <@U06NHQZCX2S> - today you can hit `POST /create_flow_run_from_deployment` from within an azure function that you have setup to trigger when a file lands (im more familiar personally with SNS -&gt; lambda personally, but should be roughly the same idea in azure)

but stay tuned for an update in the relatively near future that will make this easier

hey Nate, thanks for the reply.
The Azure part is straight forward, I will probably use
1. File Created => Bus Service
2. Bus Service => Azure Functions
3. This part is somewhat confusing though, Azure Functions -> Prefect.
Ideally on step 3 we would use webhooks or expose some simple API, but I am not sure why we can’t use that webhook syntax when deploying “locally” (other than Prefect Cloud). Can you provide more instructions regarding your `POST /create_flow_run_from_deployment`

My objective is to trigger a simple flow by an http request from an external service

Many thanks once again!

Just to clarify, if you can point me to some post, provide any example or whatever helps me figure this out. being able to add this layer of observability to the functions triggers would really enhance the use case for me, thanks

hi <@U06NHQZCX2S> - for now, using prefect server you'd have to<https://discourse.prefect.io/t/how-to-create-a-flow-run-from-a-deployment-with-rest-api-via-http-client/3159| hit your own Prefect REST API> from the azure function (3), POSTing parameters to `/create_flow_run_from_deployment` with some http client like curl / requests / httpx

in your case you should be able to build your `parameters` / call your existing deployments from within the azure function based on the features of the event you get from azure's `Bus Service`, and see your flow runs in the UI after

*(Events and Automations are currently cloud-only services - but in case it's ever useful)*
in cloud, when you curl a prefect webhook you're creating an `Event` that an `Automation` can listen for, observe, and/or take `action` in response to (if a `trigger` is activated)

you could create a webhook with a jinja template to render the JSON your flow run needs for its `parameters` then point anything at that (<https://github.com/zzstoatzz/gh/blob/main/examples/on_event/do.py|e.g.> GitHub API can send you github repo events)

a `trigger` defines when to execute the `action` in terms of:
• which types of `Event` you to `expect` to see with certain features (e.g. `my.webhook.called` with some label)
• how many instances of those events we should see before doing something (`threshold`)
an `action` is what do actually do when a `trigger` is activated / executed:
• `Run a Deployment` is a common `action`
so ultimately in cloud we also `POST` json serializable `parameters` to `/create_flow_run_from_deployment` but via the `Events` system instead