Google Cloud Redis

Warnings

• gotcha Connecting to a Memorystore for Redis instance from your application typically requires setting up Serverless VPC Access or VPC Network Peering. Direct public IP access is not usually available, and applications must be within the same VPC network or connected via a connector to access the Redis instance. Ensure your application's region aligns with your Redis instance's region for optimal connectivity and performance.
  Fix: Configure Serverless VPC Access for serverless environments (Cloud Functions, App Engine Standard) or VPC Network Peering for VM-based applications. Ensure client applications are deployed in the same region and VPC as the Redis instance, or have appropriate network connectivity configured.
• gotcha This library (`google-cloud-redis`) is for *managing* Google Cloud Redis instances (creating, listing, deleting). To *interact with data* in a Redis instance (e.g., `GET`, `SET`, `HSET`), you need a separate Redis client library like `redis-py`.
  Fix: Install `redis` (or `redis-py`) using `pip install redis` to perform data operations. Use the host, port, and optional AUTH string obtained from the `google-cloud-redis` client to connect `redis-py`.
• breaking Google Cloud client libraries sometimes introduce breaking changes in major version releases. Always consult the changelog and release notes on the official GitHub repository or Google Cloud documentation when upgrading across major versions to understand API changes, parameter shifts, or behavioral modifications.
  Fix: Review the official release notes and migration guides for the specific major version you are upgrading to. Test your application thoroughly in a staging environment before deploying to production.
• gotcha Enabling Redis AUTH for your Memorystore instance provides an authentication token (UUID) for client connections. This enhances security but requires clients to explicitly authenticate. Furthermore, enabling in-transit encryption (TLS) is a critical best practice for securing data communication between your application and the Redis instance.
  Fix: When creating or updating an instance, enable AUTH and transit encryption. Retrieve the AUTH string via `gcloud redis instances get-auth-string` or the client library, and configure your `redis-py` client (or equivalent) to use this password and TLS when connecting. Ensure your client library supports TLS.
• gotcha Many Google Cloud operations, particularly instance creation or updates, are long-running operations (LROs). The client library returns an `Operation` object. You must explicitly call `.result()` on this object to wait for the operation to complete and retrieve its final status or result, or handle it asynchronously.
  Fix: Always handle the `Operation` object returned by methods like `create_instance` or `update_instance`. Use `operation.result()` for synchronous waiting or `operation.add_done_callback()` for asynchronous handling to ensure the operation has finished successfully or to catch errors.

Install

• pip install google-cloud-redis Install stable version

Imports

• CloudRedisClient

  from google.cloud import redis_v1

Quickstart

This quickstart demonstrates how to initialize the Google Cloud Redis client and list existing Redis instances within a specified Google Cloud project and location. For authentication, ensure `GOOGLE_APPLICATION_CREDENTIALS` is set up (e.g., pointing to a service account key file, or rely on Application Default Credentials).

import os
from google.cloud import redis_v1

# Your Google Cloud Project ID
project_id = os.environ.get('GOOGLE_CLOUD_PROJECT', 'your-project-id')
# The region where you want to list instances, e.g., 'us-central1'
location = 'global' # Or a specific region like 'us-central1'

def list_redis_instances(project_id: str, location: str):
    """Lists all Redis instances in a given project and location."""
    client = redis_v1.CloudRedisClient()
    parent = f"projects/{project_id}/locations/{location}"

    try:
        # The `list_instances` method returns an iterable of Instance objects.
        instances = client.list_instances(parent=parent)

        if not instances:
            print(f"No Redis instances found in {location} for project {project_id}.")
            return

        print(f"Redis instances in {location} for project {project_id}:")
        for instance in instances:
            print(f"  Name: {instance.name}")
            print(f"  Host: {instance.host}")
            print(f"  Port: {instance.port}")
            print(f"  State: {instance.state.name}")
            print(f"  Tier: {instance.tier.name}")
            print(f"  Memory size (GB): {instance.memory_size_gb}")
            print("  ---")

    except Exception as e:
        print(f"Error listing Redis instances: {e}")

if __name__ == "__main__":
    # Set GOOGLE_CLOUD_PROJECT environment variable or replace 'your-project-id'
    # Ensure GOOGLE_APPLICATION_CREDENTIALS is set up for authentication
    list_redis_instances(project_id, location)