Kyma APIRule Creation and Exposure
The concept name provided is "undefined," and the available sources do not supply a clear, specific definition for a named SAP developer concept. Based on the sources, which cover topics such as Wildcard Host, Short Host Name, and deploying workloads in the Kyma environment, no single coherent concept labeled "undefined" can be grounded. A developer uses an APIRule in SAP BTP, Kyma runtime to configure routing and expose services, with options such as wildcard hostnames to route traffic from matching subdomains or short host names to simplify configuration.
Tutorials that teach this
- Tutorial Implement Subscription Callbacks for a Multitenant Application
- Tutorial Deploy a Go PostgreSQL API Endpoint in SAP BTP, Kyma Runtime
- Tutorial Register a Multitenant Application to the SAP SaaS Provisioning Service
- Tutorial Deploy a Go MSSQL API Endpoint in SAP BTP, Kyma Runtime
- Tutorial Deploy the SAPUI5 Frontend in SAP BTP, Kyma Runtime
- Tutorial Create and Configure the Approuter Application for a Multitenant Application
- Tutorial Deploy a CAP Application with PostgreSQL in SAP BTP, Kyma Runtime
- Tutorial Deploy a Node.js Application in SAP BTP, Kyma runtime
- Tutorial Create Kyma Function Using Kyma CLI
- Tutorial Deploy the SAPUI5 Frontend in SAP BTP, Kyma Runtime
- Tutorial Deploy Commerce Mock Application in SAP BTP, Kyma Runtime
- Tutorial Create Kyma Function and a Microservice via UI
- Tutorial Use Redis in SAP BTP, Kyma Runtime to Store and Retrieve Data
- Tutorial Fast Prototyping in SAP BTP, Kyma Runtime Using App Push
- Tutorial Consume SAP BTP Services In SAP Kyma
Docs explaining this concept
Prerequisites
- Concept Kubernetes Custom Resource (CR) The [Registry Cache module](https://help.sap.com/docs/btp/sap-business-technology-platform/cdca828ea4ef4fd6a08088e0ba19b66c?locale=en-US&state=PRODUCTION&version=Cloud) adds a caching layer for container image registries on SAP BTP. A developer uses it to reduce the time and bandwidth required to pull container images by serving them from a local cache instead of fetching them from a remote registry each time. To enable caching, a developer creates a [RegistryCacheConfig custom resource](https://help.sap.com/docs/btp/sap-business-technology-platform/eba113235f52423b8bc0a571842fb5e6?locale=en-US&state=PRODUCTION&version=Cloud) that configures the caching behavior for the module.
- Concept Istio Sidecar Proxy Injection The concept name was not provided, but based on the sources, this definition covers **Istio Service Mesh in SAP BTP, Kyma Runtime**. Istio Service Mesh is a infrastructure layer used in SAP BTP, Kyma runtime that manages service-to-service communication through [Istio sidecar proxies](https://help.sap.com/docs/btp/sap-business-technology-platform/ca84edb503ce4999b07237e5eed9eefc?locale=en-US&state=PRODUCTION&version=Cloud) injected alongside workloads. Developers use it to secure traffic between services with mutual TLS (mTLS), expose workloads via [TLS or mTLS Gateways](https://help.sap.com/docs/btp/sap-business-technology-platform/e7c6c6a2b47744dbaa405b422e454303?locale=en-US&state=PRODUCTION&version=Cloud), and control network policies using resources such as the Sidecar resource to minimize load and footprint. It also provides troubleshooting capabilities for issues such as connection refused errors or incompatible sidecar versions after module updates.
- Concept Kubernetes Namespaces The provided sources do not contain a named concept to define — the concept supplied is "undefined." Based on the available source snippets, which cover topics such as [Kyma Runtime basic concepts](https://help.sap.com/docs/btp/sap-business-technology-platform/4a0dd09368ce40bfa3c99cae46de49e1?locale=en-US&state=PRODUCTION&version=Cloud) and [registry cache configuration](https://help.sap.com/docs/btp/sap-business-technology-platform/0771999d5751423188b55344a8b284e2?locale=en-US&state=PRODUCTION&version=Cloud), there is insufficient information to produce a grounded definition without a valid concept name. Please provide a specific SAP developer concept to define.
- Concept Serverless Functions on Kyma The concept name provided is "undefined," and the supplied sources do not define or describe a concept by that name. Based on the available sources, a definition cannot be accurately constructed without risking unsupported claims. Please provide a valid concept name so that an accurate, source-grounded definition can be written.
- Concept Kyma Environment The concept name was not provided, so a precise definition cannot be produced from the available sources. Based on the source snippets, the **Kyma environment** is a platform-as-a-service offering within [SAP Business Technology Platform (SAP BTP)](https://help.sap.com/docs/btp/sap-business-technology-platform/15547f7e7ecd47ee9fa052b0e18c7b0a?locale=en-US&state=PRODUCTION&version=Cloud) that allows developers to build, extend, and run applications and services. It supports the consumption of SAP BTP services and uses availability zones to provide resilience and high availability for workloads.
- Concept Kyma Functions (Node.js / Python) The concept name is missing or undefined, so a precise definition cannot be produced. Based on the available sources, the **Kyma Environment** is a runtime environment within SAP Business Technology Platform that developers use to build and deploy applications, Functions, and microservices. It can be interacted with through multiple interfaces, including a UI and the [Kyma CLI](https://help.sap.com/docs/btp/sap-business-technology-platform/606ec610ee4746c09d5d2bef5a85a124?locale=en-US&state=PRODUCTION&version=Cloud), enabling flexible cloud-native development workflows on SAP BTP.
- Concept Kyma Runtime deployment The concept name is undefined and cannot be determined from the provided source snippets. The sources reference SAP BTP Kyma runtime, Docker containers, and related deployment tutorials, but do not define a specific named concept that can be documented. A meaningful definition cannot be written without a valid concept name grounded in the sources.
- Concept Kubernetes Basics
- Concept Istio Service Mesh Istio is an open-source [service mesh](https://help.sap.com/docs/btp/sap-business-technology-platform/ca84edb503ce4999b07237e5eed9eefc?locale=en-US&state=PRODUCTION&version=Cloud) that developers use on SAP BTP to manage and configure communication between workloads in a Kyma cluster. It works by injecting sidecar proxies into Pods, which handle traffic management, observability, and security without requiring changes to application code. Developers use the [Istio module](https://help.sap.com/docs/btp/sap-business-technology-platform/26ffe00c24574db58697992b93f397ac?locale=en-US&state=PRODUCTION&version=Cloud) to expose workloads via VirtualService resources, secure them with JWT authentication, and configure custom Certificate Authority (CA) certificates for mutual TLS.
- Concept Kyma / Kubernetes Deployment The concept name was not provided, making it impossible to write a meaningful or accurate reference definition grounded in the supplied sources. Please provide the specific SAP developer concept to be defined.
- Concept Redis Cache Deployment and Integration