< Marvin> In Prefect 3 for a local process flow run like a h Prefect Community #ask-marvin

<@ULVA73B9P> In Prefect 3 for a local process flow...

merlin

01/18/2025, 7:22 PM

@Marvin In Prefect 3 for a local process flow run (like a hello_world.py flow called from the command line) how do I retrieve details about the current flow run from inside of the flow?

Marvin

01/18/2025, 7:22 PM

In Prefect 3.x, you can retrieve details about the current flow run from inside a flow by using the

FlowRunContext

. Here's a concise example of how to access it:

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python
from prefect.context import FlowRunContext

def my_flow():
    flow_run_context = FlowRunContext.get()
    if flow_run_context:
        print(f"Flow run ID: {flow_run_context.flow_run.id}")
        print(f"Start time: {flow_run_context.start_time}")

# Call the flow function
my_flow()

This code snippet demonstrates how to access the flow run's ID and start time. You can explore other attributes available within the

FlowRunContext

to retrieve additional details. For more information, you can refer to the source code on GitHub.

merlin

01/18/2025, 7:45 PM

@Marvin thanks that worked. How do I create a prefect.yaml deployment template for a flow using a push ECS work-pool?

Marvin

01/18/2025, 7:45 PM

To create a

prefect.yaml

deployment template for a flow using a push ECS work-pool, you'll need to follow these general steps. This template will define how your flow should be deployed and executed using Amazon ECS: 1. Set Up Prerequisites: Ensure you have an AWS account with permissions to create ECS services and IAM roles. Also, have the AWS CLI installed and configured on your local machine. 2. Define the Deployment in
prefect.yaml
: Here's a basic structure for your

prefect.yaml

file:

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yaml
   name: my-flow-deployment
   description: A deployment of my flow using ECS
   version: 1
   flow: path/to/your/flow.py
   work_pool:
     name: my-ecs-work-pool
     type: ecs
     configuration:
       # Specify the ECS task definition ARN or other configuration details
       task_definition_arn: "arn:aws:ecs:region:account-id:task-definition/my-task"
       # Optionally specify the capacity provider (EC2 or Fargate)
       capacity_provider: FARGATE
   schedule:
     cron: "0 0 * * *"  # Example schedule (midnight daily)

3. Configure ECS Work Pool: In the

work_pool

section, you can specify the ECS task definition ARN, which the worker will use when spinning up the ECS Task. You can choose between EC2 and Fargate as the capacity provider. 4. Deploy the Flow: Use the Prefect CLI or Prefect UI to register and deploy the flow using this configuration. For more detailed guidance, you can refer to the Prefect ECS Integration Guide and the Prefect Deployment Documentation.

merlin

01/21/2025, 5:16 PM

@Marvin I made a test flow of ECS push work pool, and I got this error:

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Flow run could not be submitted to infrastructure: The config profile (app-templisher) could not be found

I have a block already defined so I'm confused why the profile wasnt found. Here is the dump of block inspect:

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prefect block inspect aws-credentials/my-profile
        aws-credentials/my-profile
┌─────────────────────────────┬───────────────────────────────────┐
│ Block Type                  │ AWS Credentials                   │
│ Block id                    │ 497cXXX-XXX-XXX-XXX-XXXXXXXXX     │
├─────────────────────────────┼───────────────────────────────────┤
│ region_name                 │ us-west-2                         │
│ profile_name                │ my-profile                        │
│ aws_access_key_id           │ AKIAXXXXXXXXXXXXXXXX              │
│ aws_client_parameters       │ {'use_ssl': True}                 │
│ aws_secret_access_key       │ ********                          │
└─────────────────────────────┴───────────────────────────────────┘

Marvin

01/21/2025, 5:16 PM

The error you're encountering, "The config profile (app-templisher) could not be found," suggests a mismatch between the profile name used in your ECS work pool configuration and the profile name you've defined in your AWS Credentials block. Here's what you can do: 1. Verify Profile Name: Ensure that the profile name in your AWS Credentials block matches exactly with the profile name you're using in your ECS work pool configuration. In your block dump, the profile name is

my-profile

, so ensure this is the name being referenced in your ECS configuration. 2. AWS Configuration: Prefect uses the

boto3

client under the hood to create a session with AWS. Make sure your AWS credentials and configuration are correctly set up in your environment or provided directly through the AWS Credentials block in Prefect. 3. Infrastructure Setup: If you're setting up infrastructure manually, ensure that your AWS CLI is configured correctly and authenticated with the necessary permissions. You can also use the

provision-infra

command if you haven't set up the infrastructure yet. For more detailed guidance, you can refer to the Prefect AWS Integration documentation and Serverless Infrastructure Examples. If everything seems correct and the issue persists, double-check the environment where the flow is being executed to ensure it has access to the right AWS configuration files or environment variables.

merlin

01/21/2025, 6:11 PM

@Marvin I noticed in the AWS Credentials block there is a field called

config

which is not populated. This is not shown by

prefect block inspect

but in the UI I copied this field:

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AwsClientParameters
{ "config": null, "verify": null, "use_ssl": true, "api_version": null, "endpoint_url": null, "verify_cert_path": null }

Is there something I can place in the config? The profile name is correct.

Marvin

01/21/2025, 6:11 PM

The

config

field in the

AwsClientParameters

is used to pass additional configuration options to the

boto3

client that Prefect uses under the hood. However, this field is typically left as

null

unless you have specific configurations you need to apply. Here's what you can consider for the

config

field: - Custom Configuration: You can provide a dictionary of configuration options supported by

boto3

. This might include settings like

retries

connect_timeout

read_timeout

, or other advanced options. However, these are rarely needed for basic operations. - Default Behavior: If you don't have any specific configurations to apply, it's perfectly fine to leave this field as

null

. Prefect will use the default settings provided by

boto3

. For more details on what can be configured, you might want to refer to the boto3 documentation. If your profile name is correct and you're still facing issues, ensure that your AWS CLI is set up properly and that the AWS environment variables or credentials file are accessible in the environment where your flow is running. You can also check Prefect's AWS Integration documentation for more guidance.

merlin

01/21/2025, 6:20 PM

@Marvin When inspecting the deployment I have

work_pool_name: my-work-pool

, but I notice that

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'infrastructure_document_id': None

The work pool my-work-pool has the following defined:

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'aws_credentials': {
                    'allOf': [{'$ref': '#/definitions/AwsCredentials'}],
                    'title': 'AWS Credentials',
                    'default': {'$ref': {'block_document_id': '497-xXXX-etc'}},

And the block_document_id is correctly referencing my aws credentials block with name and profile_name =

my-profile

with AWS credentials correctly stored.

Marvin

01/21/2025, 6:20 PM

The issue you're encountering with the

infrastructure_document_id

being

None

might be due to a misconfiguration or missing setup in your work pool or deployment configuration. Here's a checklist to help you resolve this: 1. Work Pool Configuration: Ensure that the work pool is fully configured with all necessary infrastructure details. This includes specifying the infrastructure type and ensuring any required fields are completed. If you're using ECS, make sure the ECS-specific configurations are correct. 2. AWS Credentials Block: Verify that the AWS Credentials block is correctly referenced and accessible by the work pool. It seems like you've already checked this, but double-check the block ID and ensure it matches. 3. Infrastructure Setup: If you're using ECS, make sure that the ECS cluster and related resources (like task definitions and IAM roles) are correctly set up and accessible. The infrastructure might not be created or linked properly if these resources are not set up. 4. Work Pool and Deployment Linking: Ensure that the deployment is correctly linked to the work pool. This includes verifying that the deployment configuration references the correct work pool and that any necessary infrastructure documents are created and linked. For more detailed guidance, you can refer to the Prefect Work Pools documentation and the ECS Guide. If the issue persists after these checks, consider re-creating the work pool or deployment to ensure all configurations are correctly applied.

merlin

01/21/2025, 6:29 PM

@Marvin Can you help me debug the yaml definition of the deployment? I am trying to define the deployment with work-pool = 'my-work-pool' but for some reason after running

prefect deploy

it is using the default process work pool called 'idioteque':

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deployments:
- name: hello
  version: *version
  tags:
  - ecs
  - test
  description:
  entrypoint: dev/basic/debugger_flow.py:debug_hello
  parameters:
    msg: "ECS work pool from deployment"
  work_pool:
    name: my-work-pool
    work_queue_name: default
    job_variables:
      env:
        PREFECT_CURRENT_COMMIT: f129dbd2
  is_schedule_active: true

Marvin

01/21/2025, 6:29 PM

Let's review your YAML deployment configuration and identify potential issues: 1. Work Pool and Queue Names: You've specified the

work_pool

and

work_queue_name

correctly. Ensure that

my-work-pool

exists and is correctly configured in Prefect. Double-check the spelling and case sensitivity. 2. Prefect Deployment Command: When you run

prefect deploy

, make sure you're in the correct directory where this YAML file is located, or specify the path to the YAML file if necessary. 3. Deployment Overrides: Check if there are any environment variables or CLI options that might override the

work_pool

setting. Prefect might default to a different work pool if certain conditions are met. 4. Prefect Version: Ensure you're using a version of Prefect that supports the configuration you're using. If there are updates or changes in how deployments are handled, they might affect the behavior. 5. Configuration Validation: Use the Prefect CLI to validate the deployment configuration. This can help identify any issues in the YAML syntax or structure. If the configuration seems correct and the issue persists, try the following: - Recreate Work Pool: Ensure that

my-work-pool

is correctly set up and accessible. You might want to recreate it to ensure there are no hidden issues. - Verbose Output: Run

prefect deploy

with verbose output to get more information on why it might default to the 'idioteque' work pool. - Check Logs: Review the Prefect logs for any warnings or errors related to the work pool selection. If none of these steps resolve the issue, consider reaching out to the Prefect community or support for more targeted assistance.

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