update_service_type.go

package services

import (
    "fmt"
    v1 "k8s.io/api/core/v1"
    metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
    "k8s.io/client-go/kubernetes"
)

const typeAnnotation string = "original-service-type"

// Update changes the service type
func Update(namespace, name, serviceType string, client kubernetes.Interface) error {
    service, err := client.CoreV1().Services(namespace).Get(name, metav1.GetOptions{})

    if err != nil {
        return fmt.Errorf("Failed to get service in namespace \"%s\": %s", namespace, err)
    }

    if _, ok := service.ObjectMeta.Annotations[typeAnnotation]; !ok {
        service.ObjectMeta.Annotations[typeAnnotation] = string(service.Spec.Type)
    }
    service.Spec.Type = v1.ServiceType(serviceType)

    if serviceType != "NodePort" && serviceType != "LoadBalancer" {
        for i := range service.Spec.Ports {
            service.Spec.Ports[i].NodePort = 0
        }
    }

    _, err = client.CoreV1().Services(namespace).Update(service)

    if err != nil {
        return fmt.Errorf("failed to update service: %s", err)
    }

    log.Success("Updated service \"%s\" in namespace \"%s\" to %s", name, namespace, serviceType)
    return nil
}

// Revert service type (only applies if tectl has previously changes service type)
func Revert(namespace, name string, client kubernetes.Interface) error {
    service, err := client.CoreV1().Services(namespace).Get(name, metav1.GetOptions{})

    if err != nil {
        return fmt.Errorf("Failed to get service in namespace \"%s\": %s", namespace, err)
    }

    if serviceType, ok := service.ObjectMeta.Annotations[typeAnnotation]; ok {
        service.Spec.Type = v1.ServiceType(serviceType)

        if serviceType != "NodePort" && serviceType != "LoadBalancer" {
            for i := range service.Spec.Ports {
                service.Spec.Ports[i].NodePort = 0
            }
        }

        delete(service.ObjectMeta.Annotations, typeAnnotation)
        _, err = client.CoreV1().Services(namespace).Update(service)

        if err != nil {
            return fmt.Errorf("failed to update service: %s", err)
        }

        log.Success("Reverted service \"%s\" in namespace \"%s\" to %s", name, namespace, serviceType)
        return nil
    }

    return fmt.Errorf("unable to find required annotation")
}