@Marvin I'm following how to define class instance methods as flows from the documentation. When I deploy the flow to prefect cloud,

self

is listed as a parameter and I get this error: Error creating flow run: Validation failed. Failure reason: 'self' is a required property" What should be done?

It seems like there's a known issue with using class instance methods as flows in Prefect due to the handling of the

self

parameter. Prefect currently requires explicit handling of

self

since it is considered a parameter in the flow's signature. The good news is that there's been a pull request to add support for decorating instance/class/static methods as

@flows

or

@tasks

. The issue arises because the implicit

self

parameter is not handled automatically by Prefect. This causes errors such as: "Error binding parameters for function 'instance_method': missing a required argument: 'self'. Function 'instance_method' has signature 'self' but received args: () and kwargs: []." The solution being implemented involves: 1. Adding a

__get__

method that helps bind the instance method correctly when accessed on its parent instance. 2. Modifying Prefect's

get_call_parameters

function to look for a

__prefect_self__

attribute and handle it as if it was a normal parameter. This should eventually allow you to define flows and tasks using class methods without manually handling

self

as an argument. For now, as a workaround, you might consider making these methods into standalone functions or passing your class instance as an explicit parameter until these changes are fully integrated and released in a future version. You can follow the progress and updates on this topic through the pull request Add support for instance/class/static methods. If you're having trouble determining the Prefect version you are using, please check with your local environment or project setup, as the solution or workaround may vary based on your version.

@Nate I saw your response in the thread here: https://prefect-community.slack.com/archives/C048ZHT5U3U/p1728310080981169 I can't tell if this is supposed to work or not. Your response is no but the PR is merged and the docs say its possible: https://docs.prefect.io/3.0/develop/write-flows#class-methods

> I guess the distinction is that a flow can be written and run as an instance method but deployment doesn't seem to be supported yeah that's right, we should be more intentional about this in the docs. and perhaps open a PR to make "instance methods as deployments" work