You are building a new version of an application hosted in an App Engine environment. You want to test the new version with 1% of users before you completely switch your application over to the new version. What should you do?

Google App Engine is designed to support multiple versions of an application simultaneously. The platform's native traffic splitting feature allows you to incrementally roll out changes by directing a specific percentage of traffic to a new version. This is the standard method for performing A/B testing or canary deployments. Deploying the new code as a new version within the same application and then using the Google Cloud Console to configure the traffic split is the most direct and intended approach to achieve the goal.

A. Migrating to Google Kubernetes Engine is a major architectural change and is not the correct procedure for testing a new version of an existing App Engine application.
B. Migrating to Compute Engine is an unnecessary platform change that ignores the built-in versioning and traffic management capabilities of App Engine.
C. Traffic splitting in App Engine is managed between different versions within a single application/service, not between two entirely separate applications. This approach is functionally incorrect.

1. Google Cloud Documentation - App Engine - Splitting Traffic: "App Engine allows you to split incoming traffic for your app between two or more of its versions. Splitting traffic allows you to do A/B testing between your versions and provides control over the pace when rolling out features." This document explicitly describes the process in option D.

Source: Google Cloud Documentation

"Splitting Traffic"

App Engine standard environment for Python 3 docs.

2. Google Cloud Documentation - App Engine - How Requests are Routed: "Within a single project

you can deploy multiple apps as services. [...] Each service can have multiple versions

and you can split traffic between those versions." This clarifies that versions exist within a service/app

making option C incorrect.

Source: Google Cloud Documentation

"How Requests are Routed"

App Engine Concepts.

3. Google Cloud Documentation - Deploying a new service or version: "When you deploy a new version

you can choose to either immediately route traffic to it or deploy it without routing traffic and then later assign traffic to it." This confirms that deploying a new version is the first step

followed by traffic management.

Source: Google Cloud Documentation

"Deploying a new service or version"

App Engine standard environment for Python 3 docs.