Fast forward a few years. Kate is now a cloud-native developer who has been building cutting-edge applications for years. Using the latest tools and technologies, she has helped the bank lead the industry in offering new and innovative services to customers. From her previous experience at the bank, she knows that mainframes still host core systems. She and her team consider this platform to be legacy technology. In a recent conversation, the topic of migration came up, and the focus was on when, not if, her team would be tasked with moving key applications and services to the cloud.
Recently, she was asked by the CIO to work on a new application, which represented the next step forward in the bank’s investment and trading platform. Though expected to be available on any device, the CIO outlined several key requirements. The application needed to easily handle high volumes of transactions and provide fast, almost real-time processing times. It would also need to have extremely low latency and provide users with detailed insights based on the bank’s rich information, along with a detailed analysis of portfolio and individual stock performance. Her leadership team was insistent that time was of the essence if the bank was to compete in the new markets the platform would unlock, and that the development team would need to move quickly.
During the planning phase, Kate and her team were made aware of a mainframe application that hosted and maintained much of the information she needed for the new platform. Initially, the team thought that migrating this application to the cloud would be the best approach. However, after some initial investigations, they realized that migrating the complex and highly regulated application would take many months if not years.
Kate and her team decide that it would be much more cost-effective and faster to leave the mainframe application as it is. They decide to work with the mainframe development team to build a set of REST (representational state transfer) APIs that will allow the Azure application to interface with the mainframe and to securely request information. Adopting this approach which allows her team to focus time and effort on customer value, they follow these steps:
- Kate and her team identify the information they need and work with the mainframe team to identify the APIs that will allow them to access the necessary data and business logic.
- The mainframe team create a set of RESTful APIs and use a tool—such as IBM API Connect® and z/OS® Connect—to create API definitions and generate API documentation and client code.
- They set up an API Gateway in Azure API Management to configure an entry point for the Azure application to access the mainframe APIs. Kate and her team get started on the Azure application using the generated API documentation and client code provided to make API calls to the mainframe system.
- As the Secure by Design approach is a critical part of the bank’s approach to development, the team helps ensure that an identity solution is put into place at the beginning. This strategy is to enable the team to handle authentication and authorization correctly and ensure that only authorized users and applications such as the bank’s new investment and trading platform can access the mainframe system through the APIs.
After several weeks of development, Kate’s team completes the integration between the Azure application running on Azure and the mainframe system. They test the Azure application thoroughly to help ensure that it works as expected, is able to communicate with the mainframe correctly, and that the mainframe system can handle the increased load. The result is a modern web application that provides customers with a seamless user experience while leveraging the power of the mainframe system. Customers can interact with the application without realizing that they are accessing resources on the mainframe.
Integrating an Azure application with a mainframe system using APIs requires careful planning, collaboration between teams, and a solid understanding of both Azure and mainframe technologies. By using APIs to bridge the gap between the old and the new, developers like Kate are able to create modern applications that provide the best of the new, leveraging the power of the mainframe while providing a seamless user experience.
