<@ULVA73B9P> explain can i just define all block i...
# ask-marvin
s
@Marvin explain can i just define all block in a file and create all with a cli command -
prefect block register
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prefect block register [OPTIONS]
Register blocks types within a module or file. This makes the blocks available for configuration via the UI. If a block type has already been registered, its registration will be updated to match the block’s current definition. Examples: Register block types in a Python module: $ prefect block register -m prefect_aws.credentials Register block types in a .py file: $ prefect block register -f my_blocks.py --module Python module containing block types to be registered --file Path to .py file containing block types to be registered
m
thought for 27.3 seconds
Yes, you can define multiple block types in a single Python file and register them all at once using the
prefect block register
command. This is a convenient way to make your custom blocks available in the Prefect UI. Here's how it works: 1. Create a Python file (e.g.,
my_blocks.py
) containing your block definitions:
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python
from prefect.blocks.core import Block

class MyFirstBlock(Block):
    value: str
    
class MySecondBlock(Block):
    number: int
    text: str
    
class MyThirdBlock(Block):
    url: str
    token: str
2. Register all blocks in the file using:
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bash
prefect block register -f my_blocks.py
Or if your blocks are in a Python module:
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bash
prefect block register -m your_module_name
After registration, these blocks will be available in the Prefect UI for configuration. The registration process will: - Make the blocks visible in the UI - Update any existing block registrations if the block definitions have changed - Allow you to create and configure instances of these blocks through the UI You can find more details about blocks in the Prefect documentation. Remember that built-in blocks should be automatically registered when you start a Prefect server for the first time, so you only need to use this command for custom blocks or if auto-registration fails.
s
@Marvin I dont want to configure through UI, can I not configure everythng from CLI
m
thought for 52.6 seconds
Yes, you can configure blocks entirely through Python code and CLI without using the UI. Here's how: 1. First, create a Python file (e.g.,
blocks.py
) with your block configurations:
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python
from prefect.blocks.system import Secret
from prefect.blocks.notifications import SlackWebhook
# Import other block types you need

# Create and save blocks
Secret(value="my-secret-value").save("my-secret-name")

SlackWebhook(
    url="<https://hooks.slack.com/services/xxx/yyy/zzz>"
).save("my-slack-webhook")

# Add more block configurations as needed
2. You can then run this Python file to create all blocks:
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bash
python blocks.py
To manage blocks via CLI, you can use these commands:
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bash
# List all available block types
prefect block ls

# List all configured blocks
prefect block ls --type secret  # List all blocks of type 'secret'

# Create a block (will prompt for required values)
prefect block create secret

# Delete a block
prefect block delete secret/my-secret-name
For automation purposes, you can also create blocks using environment variables. For example:
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python
import os
from prefect.blocks.system import Secret

# Create block from environment variable
Secret(value=os.environ["MY_SECRET_VALUE"]).save("my-secret-name")
This approach allows you to: - Version control your block configurations - Automate block creation as part of your deployment process - Avoid manual UI configuration - Use environment variables for sensitive values Remember that some blocks (like the Secret block) are built into Prefect, while others might need to be installed from separate packages (like
prefect-aws
or
prefect-gcp
).
s
@Marvin can i export this kind of file from an existing UI
m
thought for 78.6 seconds
While there isn't a direct "export" button in the UI, you can use the
prefect block inspect
command to view the configuration of existing blocks, and then recreate them in Python code. Here's how: 1. First, list your existing blocks:
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bash
prefect block ls
2. Then inspect a specific block to see its configuration:
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prefect block inspect secret/my-secret-name
3. Using the output from the inspect command, you can create a Python file that recreates these blocks. Here's an example workflow:
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python
from prefect.blocks.system import Secret
from prefect.blocks.notifications import SlackWebhook
# Import other block types you need

# Recreate blocks based on the inspected configurations
Secret(
    value="your-secret-value"
).save("my-secret-name")

SlackWebhook(
    url="<https://hooks.slack.com/services/xxx/yyy/zzz>"
).save("my-slack-webhook")

# Add more blocks as needed
While there isn't an automated export feature, you can: 1. Use
prefect block ls
to list all your blocks 2. Use
prefect block inspect
on each block to see its configuration 3. Create a Python script that recreates these blocks using the Prefect Python SDK Note that for sensitive values (like secrets or API keys), you'll want to: - Use environment variables instead of hardcoding values - Consider using a secrets management system - Be careful not to commit sensitive values to version control This approach, while manual, gives you the benefit of having your block configurations in code, making them: - Version controllable - Reproducible across environments - Automatable as part of your deployment process