<@ULVA73B9P> I am trying this to dynamically creat...
# ask-marvin
b
@Marvin I am trying this to dynamically create a flow def create_flow(deployment_name: str, command: str): """Dynamically create a flow with the given deployment name""" @flow(name=deployment_name) def automation_executor(): task_result = execute_shell_command(command) return task_result return automation_executor but I encounter error saying Flow function with name '*****"' not found in file*8
m
The error you're encountering, "Flow function with name '***' not found in file," typically happens when Prefect tries to locate a flow by name in a file, but it doesn't find it. This can occur if you're using Prefect in a way that doesn't align with its expectations for flow discovery, especially when dynamically creating flows. Here's how you might resolve this: 1. Ensure Proper Flow Registration: Prefect expects flows to be registered or discovered in a certain way. When dynamically creating flows, ensure that they are properly registered with Prefect's orchestration tools if you intend to run them outside of immediate execution. 2. Check Deployment Configuration: If you're deploying this flow, make sure the deployment configuration points to the correct file and flow name. Prefect requires that the flow's name matches the one specified in the deployment configuration. 3. Avoid Dynamic Names for Deployment: If you're dynamically creating flows and also deploying them, ensure that the deployment system can correctly identify and register these flows. Prefect might not handle dynamically named flows well if it expects a static flow name for deployment. 4. Execution Context: If you're running the flow directly after creation, ensure that the context in which you're executing the flow has access to the defined function. Here's a simple example of how you might structure your flow:
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python
from prefect import flow, task

@task
def execute_shell_command(command: str):
    import subprocess
    result = subprocess.run(command, shell=True, capture_output=True)
    return result.stdout.decode()

def create_flow(deployment_name: str, command: str):
    """Dynamically create a flow with the given deployment name"""
    @flow(name=deployment_name)
    def automation_executor():
        task_result = execute_shell_command(command)
        return task_result

    return automation_executor

# Example usage
flow_instance = create_flow("my_dynamic_flow", "echo Hello, World!")
flow_instance()  # This will execute the flow immediately
For more detailed information, you might want to explore Prefect's documentation on deployments and troubleshooting. Let me know if you have any further questions.
b
@Marvin this is where I am ceating deployment
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def create_deployment(args):
    """Create a new deployment with the given arguments"""
    data = args
    try:

        # Dynamically create the flow with the deployment name
        flow_instance = create_flow(data['deployment_name'], data['command'])

        # Deploy the flow using the .deploy() method
        deployment_result = flow_instance.from_source(
            source=str(Path(__file__).parent.resolve()),
            entrypoint=f"{Path(__file__).name}:{data['deployment_name']}"
        ).deploy(
            name=data['deployment_name'],
            work_pool_name=data.get('work_pool', 'cla-infra'),
            cron=data['cron_schedule'],
            concurrency_limit=data.get('concurrency_limit', 1)
        )

        # Return the deployment result in the response
        return make_response(jsonify(data=[], success=True, messages=[f"Deployment created successfully. Result: {deployment_result}"]), 200)

    except Exception as e:
        # Capture and return any errors during deployment
        out_error_msg = {"error": "Problem in creating deployment", "message": str(e)}
        return make_response(jsonify(data=[], success=False, messages=[out_error_msg]), 500)
m
The error you're encountering seems to be related to the way Prefect is handling the entrypoint for the deployment. Here's what you need to know: 1. Entrypoint Format: The entrypoint must be a relative reference to a function decorated as a flow. It uses Python’s standard path-to-object syntax, like
path/to/file.py:function_name
. 2. Flow Name Matching: The entrypoint must reference the same flow as the flow ID. This means that the function name in your entrypoint should match the flow function's name. 3. Dynamic Flow Naming: You might be dynamically creating flows, but Prefect's deployment requires a static reference to the flow function. This can be problematic if you're using dynamic names for the flow function itself. 4. File Location: Ensure that the file location and the function name in the entrypoint are correct and accessible at the time of deployment. Here's a refined approach to your deployment creation function:
Copy code
python
from prefect import flow, task
from pathlib import Path
from flask import jsonify, make_response

@task
def execute_shell_command(command: str):
    import subprocess
    result = subprocess.run(command, shell=True, capture_output=True)
    return result.stdout.decode()

def create_flow(deployment_name: str, command: str):
    """Dynamically create a flow with the given deployment name"""
    @flow(name=deployment_name)
    def automation_executor():
        task_result = execute_shell_command(command)
        return task_result

    return automation_executor

def create_deployment(args):
    """Create a new deployment with the given arguments"""
    data = args
    try:
        # Dynamically create the flow with the deployment name
        flow_instance = create_flow(data['deployment_name'], data['command'])

        # Deploy the flow using the .deploy() method
        deployment_result = flow_instance.from_source(
            source=str(Path(__file__).parent.resolve()),
            entrypoint=f"{Path(__file__).name}:automation_executor"
        ).deploy(
            name=data['deployment_name'],
            work_pool_name=data.get('work_pool', 'cla-infra'),
            cron=data['cron_schedule'],
            concurrency_limit=data.get('concurrency_limit', 1)
        )

        # Return the deployment result in the response
        return make_response(jsonify(data=[], success=True, messages=[f"Deployment created successfully. Result: {deployment_result}"]), 200)

    except Exception as e:
        # Capture and return any errors during deployment
        out_error_msg = {"error": "Problem in creating deployment", "message": str(e)}
        return make_response(jsonify(data=[], success=False, messages=[out_error_msg]), 500)
In this example, the
automation_executor
function name is used directly in the entrypoint, ensuring that the function is correctly referenced. Make sure that the flow function name matches the one used in the entrypoint. For more information, you can refer to the Prefect documentation on deployments.
b
@Marvin I still see this
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Flow function with name 'automation_executor' not found in ***.py
m
The error "Flow function with name 'automation_executor' not found in *.py" suggests that Prefect is unable to locate the flow function within the specified file. Here are a few things to check and consider: 1. Correct Entrypoint: Ensure the entrypoint is correctly pointing to the file and function. The format should be
filename.py:function_name
. Double-check that
automation_executor
is the correct function name and that it exists in the specified file. 2. File Structure: Ensure that the file containing the
automation_executor
function is indeed the file you're referencing in the deployment configuration. The function must be directly accessible in the file specified. 3. Flow Definition: The flow function must be decorated with
@flow
. Ensure that the
automation_executor
function is properly defined and decorated within the same file. 4. Dynamic Flow Creation: If you're dynamically creating the flow, ensure that the dynamic nature doesn't interfere with Prefect's ability to statically reference the flow function. Prefect expects a static reference for deployment purposes. 5. Script Execution Context: Make sure the script is executed in an environment where the file and function structure matches what Prefect expects. This includes running the script from the correct directory and ensuring all dependencies and paths are correctly set up. Here's a checklist to ensure everything is in place: - [ ] The file name in the entrypoint matches the actual file name. - [ ] The function name in the entrypoint matches the actual function name. - [ ] The function is decorated with
@flow
. - [ ] The file is in the correct directory and accessible at runtime. If all these are correct and you're still facing issues, consider simplifying the flow creation to ensure that the dynamic creation doesn't interfere with Prefect's static requirements. If needed, you might want to manually specify the flow in a separate file to test if the deployment works with a static flow definition.