How to make calls between internal services in k8s?

In Kubernetes, services can communicate with each other in the following ways:

1. By utilizing Service Discovery: Services in Kubernetes can discover and communicate with each other through a service discovery mechanism. Each service has a unique DNS name, which can be used to access other services. For example, if a service is named “my-service,” it can be accessed via “http://my-service.”
2. Kubernetes can inject service-related information such as IP addresses and ports into containers in the form of environment variables. By reading these variables, services can directly access the addresses and port information of other services for calling.
3. By utilizing Kubernetes Service objects, one or multiple Pods can be provided with a unified entry point. The Service object exposes the service’s access address and port, allowing other services to call the service by accessing the Service object’s address and port.
4. By using Kubernetes DNS, services in a Kubernetes cluster can be resolved to their IP addresses using DNS names. Services can call other services by using their DNS names instead of directly using IP addresses.
5. By utilizing Kubernetes Ingress objects, external access requests can be routed to specific services. By configuring Ingress rules, services can be exposed to external access through public domain names and paths.

There are various common ways to call services within Kubernetes, and the specific choice depends on the application’s requirements and architecture.