Spring Cloud Gateway helped AARP modernize their applications gradually without impacting functionality or metrics. It allowed them to route traffic between legacy and new microservices, perform throttling and traffic splitting incrementally, and support blue-green deployments. Spring Cloud Gateway provided a simpler, more developer-friendly solution than other products for orchestrating their modernization through routing configuration.

1. How Spring Cloud Gateway
Orchestrated Our App
Modernization
SpringOne 2021
Partha Chandramohan and Dodd Pfeffer
September 2021

2. Who is AARP
2 • SpringOne 2021
AARP is a nonprofit, nonpartisan organization that empowers
people to choose how they live as they age.
AARP has been around since 1958 and serves more than 40
million members today. We actively advocate for healthcare,
social security, health insurance and other such on behalf of our
members.
We also provide many other discounts and benefits.

3. DSM Background
3 • SpringOne 2021
DSM manages the Digital and Membership Strategies for AARP. That includes the technology and production of content
on AARP.org and the AARP Now app and strategies that help us acquire, maintain and bring value to members.

4. Legacy setup
• No meaningful auto-scaling
• No gateway
• No throttling
• No rule-based routing
4 • SpringOne 2021
EC2-Tomcat-App2
EC2-Tomcat-App2
EC2-Tomcat-App1
EC2-Tomcat-App1
EC2-Tomcat-App3
EC2-Tomcat-App3
EC2-Tomcat-App4
EC2-Tomcat-App4
ELB
ELB
ELB
ELB
Web
Server

5. Solution needed for
• Migrate to modernized applications gradually without impacting
the functionality, application metrics and with a quick rollback strategy
to the original state
• Throttle the traffic into the new applications incrementally
• Route traffic to legacy and new service at the same time
3 • SpringOne 2021

6. Modernization strategy
6 • SpringOne 2021
• Broke down monolithic apps
• Gradually peel off one service at a time
• Wanted to be able to route traffic to legacy and new service
• SCG was the solution to do the route
• AB testing
• Traffic splitting
• Rules: Header values

7. Blue-Green deployments
7 • SpringOne 2021
Having blue-green deployment strategy was a requirement for us that was
outlined as part of app modernization project.
Spring cloud gateway became the fundamental enabler to achieve this.

8. The setup
8 • SpringOne 2021
W
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Legacy platform
Tanzu platform
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9. Spring Cloud Gateway is better?
9 • SpringOne 2021
• Developer friendly
• Works seamlessly with the platform
• Keeps things simple
• Easy integration
• Comprehensive configuration list
• Avoids the need for other expensive products

10. Thank you