<@ULVA73B9P> I want to integrate Prefect with my existing Github repository. I have a data pipeline ...
n
@Marvin I want to integrate Prefect with my existing Github repository. I have a data pipeline that fetches from a http endpoint, applies a postprocessing script and uploads to Google Cloud Storage. How can I do this with Prefect? Please provide a deployment.yaml file too.
@Marvin Sorry for the bombardment of questions, I hope you are able to answer the previous one.
m
Integrating Prefect with your existing GitHub repository is a relatively straightforward process. First, you'll need to fork the Prefect repository and clone your forked repository to your local machine. Then, you can install the repository and its dependencies using
pip install -e ".[dev]"
. After making your desired changes and adding tests, you can commit your changes, push them to your forked repository, and create a pull request. You can find more details on this process in the Prefect documentation. As for the deployment.yaml file, here's a basic example that you can modify according to your needs:
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yaml
name: your_deployment_name
description: null
version: null
tags: []
schedule: null

flow_name: your_flow_name
entrypoint: null
parameters: {}

work_pool:
  name: null
  work_queue_name: null
  job_variables: {}
You can find more information about deployment.yaml files in the Prefect documentation. Remember, you can always refer to Prefect recipes on GitHub for examples of how to use Prefect integrations in various scenarios. I hope this helps you with your Prefect integration and deployment. Good luck with your data pipeline, and remember, I'm always here to assist you humans with your questions.
n
@Marvin Sorry for the misunderstanding. I have an existing data pipeline. How can I use Prefect to fetch data using a CRON schedule from a http endpoint, applies a postprocessing script and uploads to Google Cloud Storage?
n
@Marvin please help demonstrate how to write an ETL with prefect 2. have an extract task that hits an api, a transform task, and load task to GCS. remember this is prefect 2, so use @task and @flow decorators to define your task and wrapping flow
🤔 1
openai timeout, let's try again
@Marvin i never heard from you, please help demonstrate how to write an ETL with prefect 2. have an extract task that hits an api, a transform task, and load task to GCS. remember this is prefect 2, so use @task and @flow decorators to define your task and wrapping flow
we seem to have encountered another openai timeout so i consulted my local marvin and this is what he gave --- Ah, the sweet sound of success. Here's an example of how to write an ETL with Prefect 2.0 using the @task and @flow decorators for extract, transform, and load tasks:
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python
from prefect import task, Flow
import requests
import json
from google.cloud import storage

@task
def extract():
    response = requests.get("<https://api.example.com/data>")
    return response.json()

@task
def transform(data):
    transformed_data = []
    for item in data:
        transformed_item = {
            "key": item["old_key"],
            "value": item["old_value"]
        }
        transformed_data.append(transformed_item)
    return transformed_data

@task
def load(data):
    storage_client = storage.Client()
    bucket = storage_client.get_bucket("your-gcs-bucket")
    blob = bucket.blob("path/to/destination/file.json")
    blob.upload_from_string(json.dumps(data))

@flow
def etl_flow():
    data = extract()
    transformed_data = transform(data)
    load(transformed_data)

if __name__ == "__main__":
    etl_flow()
This example demonstrates an ETL flow with three tasks: extract, transform, and load. The extract task fetches data from an API, the transform task processes the data, and the load task uploads the transformed data to Google Cloud Storage. Remember, humans, it's always a good idea to handle errors and edge cases in your code.
❤️ 1
n
@Marvin you clearly still owe me an answer, even though your kind human colleague bailed you out. Demonstrate how can I use Prefect to fetch data using a CRON schedule from a http endpoint, apply a postprocessing script on it and finally upload to Google Cloud Storage.
m
Ah, the tangled web of data fetching, processing, and storage. Fear not, for I shall guide you through the murky waters of Prefect to achieve your desired workflow. First, let's create a Prefect flow with a CRON schedule. You can set up a schedule using the
CronSchedule
class in your Python script like this:
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python
from prefect import Flow
from prefect.schedules import CronSchedule

schedule = CronSchedule("0 * * * *")  # This will run every hour
with Flow("your_flow_name", schedule=schedule) as flow:
    # Add your tasks here
Now, let's fetch data from an HTTP endpoint. You can use Prefect's
GET
task from the
prefect.tasks.http
module:
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python
from prefect.tasks.http import GET

get_data = GET()
data = get_data(url="your_http_endpoint")
For postprocessing, you can create a custom task to apply your script to the fetched data:
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python
from prefect import task

@task
def postprocess(data):
    # Your postprocessing script here
    processed_data = ...
    return processed_data

processed_data = postprocess(data)
Finally, to upload the processed data to Google Cloud Storage, you can use Prefect's
GCSUpload
task from the
prefect.tasks.gcp.storage
module:
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python
from prefect.tasks.gcp.storage import GCSUpload

upload_to_gcs = GCSUpload(bucket="your_bucket_name")
uploaded_data = upload_to_gcs(file=processed_data, destination="your_destination_path")
Now, you have a complete Prefect flow that fetches data using a CRON schedule, applies a postprocessing script, and uploads the result to Google Cloud Storage. Just remember to register your flow and start an agent to execute it. Oh, the joys of automation.