I have an application that is running inside of Kubernetes which needs to display a map using Leaflet, the map data comes from Openstreetmap.

The code I use to set up the map looks like this:

map = L.map('mapid', {
        center: [lat, long],
        zoom: 19
    });
    L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
        attribution: '© <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors'
    }).addTo(map);

What is bothering me right now is the url {s}.tile.openstreetmap.org. As the openstreetmap data resides outside the k8s cluster, I need to create a Service in Kubernetes.

I tried to define these services:

apiVersion: v1
kind: Service
metadata:
  name: a.tile.openstreetmap.org
spec:
  type: ExternalName
  externalName: a.tile.openstreetmap.org
---
apiVersion: v1
kind: Service
metadata:
  name: b.tile.openstreetmap.org
spec:
  type: ExternalName
  externalName: b.tile.openstreetmap.org
---
apiVersion: v1
kind: Service
metadata:
  name: c.tile.openstreetmap.org
spec:
  type: ExternalName
  externalName: c.tile.openstreetmap.org

However that resulted in the following error message when deploying the service:

Error from server (Invalid): error when creating "openstreetmap-service.yaml": Service "a.tile.openstreetmap.org" is invalid: metadata.name: Invalid value: "a.tile.openstreetmap.org": a DNS-1035 label must consist of lower case alphanumeric characters or '-', start with an alphabetic character, and end with an alphanumeric character (e.g. 'my-name',  or 'abc-123', regex used for validation is '[a-z]([-a-z0-9]*[a-z0-9])?')
Error from server (Invalid): error when creating "openstreetmap-service.yaml": Service "b.tile.openstreetmap.org" is invalid: metadata.name: Invalid value: "b.tile.openstreetmap.org": a DNS-1035 label must consist of lower case alphanumeric characters or '-', start with an alphabetic character, and end with an alphanumeric character (e.g. 'my-name',  or 'abc-123', regex used for validation is '[a-z]([-a-z0-9]*[a-z0-9])?')
Error from server (Invalid): error when creating "openstreetmap-service.yaml": Service "c.tile.openstreetmap.org" is invalid: metadata.name: Invalid value: "c.tile.openstreetmap.org": a DNS-1035 label must consist of lower case alphanumeric characters or '-', start with an alphabetic character, and end with an alphanumeric character (e.g. 'my-name',  or 'abc-123', regex used for validation is '[a-z]([-a-z0-9]*[a-z0-9])?')

I understand that I am not allowed to use dots in .metadata.name, but is there a different possibility to achieve this? As far as I can see from the description of the leaflet source, the URL in TileLayer needs to be something like http://{s}.somedomain.com/blabla/{z}/{x}/{y}{r}.png