A Guide to Build a Simple ETL Pipeline with Google Cloud Platform and Python

Introduction

In today’s data-driven world, efficiently extracting, transforming, and loading (ETL) data is paramount.

In this blog, we will explore how to build a simple ETL pipeline using Python and leverage the power of Google Cloud Platform (GCP) services to streamline the process.

Steps to Implement ETL Pipeline

Step 1: Set Up a Google Cloud Platform Project

• Sign in to the Google Cloud Console (console.cloud.google.com) and create a new project.
• Enable the necessary APIs for your project, including Compute Engine, Cloud Storage, BigQuery, and Cloud Scheduler.

Step 2: Set Up Google Cloud Storage

• Create a new bucket in Google Cloud Storage to store input and output data.
• Note the bucket name, as it will be required in the Python code.

Step 3: Develop the Python ETL Script

• Write a Python script that handles the ETL process. This script should include code for extracting data from a source, performing required transformations, and loading the transformed data into Google Cloud Storage.
• Utilize Python libraries such as Pandas, NumPy, or database connectors to facilitate data extraction and transformation tasks.
• Use the Google Cloud Storage client libraries to interact with the storage service. Install the required libraries using pip.

Here’s an example code snippet, which demonstrates a simple ETL process using Python and Google Cloud Storage

Step 4: Authenticate the Python Script with the Google Cloud Platform

• Create a service account in the Google Cloud Console, granting it the necessary permissions to access relevant resources.
• Download the service account key as a JSON file and securely store it.
• Set the environment variable ‘Google_Application_Crendentials’ in your Python script to point to the downloaded service account key file.

Step 5: Test the Python ETL Script Locally

• Run the Python script locally to validate that the ETL process functions as expected.
• Ensure that the script successfully retrieves the input data, performs the required transformations, and stores the transformed data in the desired format in Google Cloud Storage.

Step 6: Set up Cloud Scheduler and Cloud Functions

• Go to the Google Cloud Console and navigate to the Cloud Scheduler service.
• Create a new job with the desired schedule (e.g., daily, hourly) and configure it to trigger a Cloud Function.
• Deploy a Cloud Function that will execute your Python ETL script. Ensure the function is triggered by the Cloud Scheduler job.
• Set up the Cloud Function to access the necessary resources, such as Cloud Storage and any specific dependencies your script requires.

Step 7: Set up Google BigQuery

• Create a BigQuery dataset to store the processed data.
• Define your data schema in BigQuery, specifying the table structure and column types.

Step 8: Modify the Python ETL Script to Load Data into BigQuery

• Enhance your Python ETL script to include the code necessary to load the processed data into BigQuery.
• Use the BigQuery client libraries to interact with the BigQuery service and load the transformed data into the designated table within the created dataset.

Conclusion

By combining the power of Python, Google Cloud Platform, and Cloud Scheduler, you can build a simple yet efficient ETL pipeline. GCP’s services, such as Cloud Storage and Compute Engine, provide the necessary infrastructure and storage.

About CloudThat