pass constant to skaffold - kubernetes

Question

I am trying to use a constant in skaffold, and to access it in skaffold profile:
example export SOME_IP=199.99.99.99 && skaffold run -p dev
skaffold.yaml
...
deploy:
helm:
flags:
global:
- "--debug"
releases:
- name: ***
chartPath: ***
imageStrategy:
helm:
explicitRegistry: true
createNamespace: true
namespace: "***"
setValueTemplates:
SKAFFOLD_SOME_IP: "{{.SOME_IP}}"
and in dev.yaml profile I need somehow to access it,
something like:
{{ .Template.SKAFFOLD_SOME_IP }} and it should be rendered as 199.99.99.99
I tried to use skaffold envTemplate and setValueTemplates fields, but could not get success, and could not find any example on web

Answer 1

Basically found a solution which I truly don't like, but it works:
in dev profile: values.dev.yaml I added a placeholder
_anchors_:
- &_IPAddr_01 "<IPAddr_01_TAG>" # will be replaced with SOME_IP
The <IPAddr_01_TAG> will be replaced with const SOME_IP which will become 199.99.99.99 at the skaffold run
Now to run skaffold I will do:
export SOME_IP=199.99.99.99
sed -i "s/<IPAddr_01_TAG>/$SOME_IP/g" values/values.dev.yaml
skaffold run -p dev
so after the above sed, in dev profile: values.dev.yaml, we will see the SOME_IP const instead of placeholder
_anchors_:
- &_IPAddr_01 "199.99.99.99"

Answer 2

To use the SKAFFOLD_SOME_IP variable that you have set in your skaffold.yaml you can write the chart template for Kubernetes Deployment like this:
apiVersion: apps/v1
kind: Deployment
metadata:
name: {{ .Chart.Name }}
labels:
app: {{ .Chart.Name }}
spec:
selector:
matchLabels:
app: {{ .Chart.Name }}
replicas: {{ .Values.replicaCount }}
template:
metadata:
labels:
app: {{ .Chart.Name }}
spec:
containers:
- name: {{ .Chart.Name }}
image: {{ .Values.image }}
env:
- name: SKAFFOLD_SOME_IP
value: "{{ .Values.SKAFFOLD_SOME_IP }}"
This will create an environment variable SKAFFOLD_SOME_IP for Kubernetes pods. And you can access it using 'go', for example, like this:
os.Getenv("SKAFFOLD_SOME_IP")