ingress-service-ref.yaml

apiVersion: kubevious.io/v1alpha1
kind: ClusterRule
metadata:
  name: ingress-service-ref
spec:
  summary: |
    Validate Ingress to Service reference.
  categories:
    - k8s
    - ingress
    - service
    - reference    
  target: |
    Api('networking.k8s.io')
      .Kind('Ingress')
  rule: |
    if (config.spec?.defaultBackend) {
      validateBackend(config.spec?.defaultBackend, 'default backend');
    }
    for(const [ruleIndex, rule] of (config.spec?.rules ?? []).entries())
    {
      if (rule.http)
      {
        for(const [pathIndex, path] of (rule.http.paths ?? []).entries())
        {
          if (path.backend)
          {
            validateBackend(path.backend, `rule [${ruleIndex}], path [${pathIndex}]`);
          }
        }
      }
    }

    function validateBackend(backend, backendName)
    {
      if (!backend.resource)
      {
        if (!backend.service)
        {
          error(`service is not set in ${backendName}`);
        }
        else
        {
          const serviceName = backend.service.name;
          const serviceItem = Api('')
                                .Kind('Service')
                                .name(serviceName)
                                .single();
          if (!serviceItem)
          {
            error(`Could not find Service ${serviceName} referenced in ${backendName}`);
          }
          else
          {
            const servicePort = backend.service.port;
            if (servicePort)
            {
              if (servicePort.name)
              {
                if (servicePort.number)
                {
                  error(`Using both port name and number at the same time in ${backendName}`);
                }
                else
                {
                  const ports = {};
                  for(const port of serviceItem.config.spec?.ports ?? [])
                  {
                    ports[port.name] = true;
                  }
                  if (!ports[servicePort.name])
                  {
                    error(`Could not find Port ${servicePort.name} in Service ${serviceName} referenced in ${backendName}`);
                  }
                }
              }
              else
              {
                if (servicePort.number)
                {
                  const ports = {};
                  for(const port of serviceItem.config.spec?.ports ?? [])
                  {
                    ports[port.port] = true;
                  }
                  if (!ports[servicePort.number])
                  {
                    error(`Could not find Port ${servicePort.number} in Service ${serviceName} referenced in ${backendName}`);
                  }
                }
                else
                {
                  error(`Should have port name or number set in ${backendName}`);
                }
              }
            }
            else
            {
              error(`port is not set in ${backendName}`);
            }
          }
        }
      }
      else
      {
        if (backend.service)
        {
          error(`Should only use resource or service in ${backendName}`);
        }
      }
    }