Why would you route traffic to multiple versions of your Cloud Run application?

Routing traffic to multiple versions of a Cloud Run application allows developers to implement various deployment strategies that enhance reliability, minimize downtime, and ensure smooth transitions between application versions.

Blue/green deployments involve running two identical environments, where one (the blue version) is the current production version and the other (the green version) is the new version. Traffic can then be gradually shifted from blue to green, allowing for easy rollback if issues arise.

Canary deployments allow for a small subset of users to test the new version of the application while the majority continue using the current version. This approach makes it possible to monitor and assess the performance of the new version with real user traffic before rolling it out to everyone.

Shadow deployments, on the other hand, route a copy of production traffic to the new version without affecting user experience. This method helps validate the performance and behavior of the new version under real-world load without making it accessible to users.

Choosing to route traffic to multiple versions of a Cloud Run application supports all of these strategies. By doing so, developers can mitigate risks associated with deploying new software, maintaining a seamless user experience while gathering important data about the new application version.