K
Q

How to use without function with helm (go) templating?

5/27/2020

I am using helm to deploy namespaces on our kubernetes clusters.

This is the template:

{{- range $namespaces := .Values.namespaces }}
{{- if ne $namespaces.name "default" }}    
apiVersion: v1
kind: Namespace
metadata:
  name: {{ $namespaces.name }}
  labels:
    name: {{ $namespaces.name }}
{{- end }}

The values file:

namespaces:
  - name: default
  - name: ingress-controller
  - name: rbac-manager
  - name: velero
  - name: test1
  - name: test2
  - name: test3

This works fine, but now I want to set a specific label for certain namespaces. default, ingress-controller, rbac-manager and velero are namespaces I don't want to set the label for, but only for team specific namespaces.. in this case test{1,2,3}. But these variable. So instead of using the has function:

{{ if has .Values.favorite.drink (list "coffee" "thee" "milk") }}mug: true{{ end }}

I would like to use the without function, but I am doing something wrong so hopefull someone can help me out with this one:

{{- range $namespaces := .Values.namespaces }}
{{- if ne $namespaces.name "default" }}    
apiVersion: v1
kind: Namespace
metadata:
  name: {{ $namespaces.name }}
  labels:
    name: {{ $namespaces.name }}
{{ $custom := without $namespaces.name "default" "ingress-controller" "rbac-manager" "velero" }}
{{- if eq $custom.name }}
    namespace: custom
{{- end }}
---
{{- end }}
{{- end }}

When I run this I get error:

Error: UPGRADE FAILED: template: namespaces/templates/namespaces.yaml:10:14: executing "namespaces/templates/namespaces.yaml" at <without $namespaces.name "default" "ingress-controller" "rbac-manager" "velero">: error calling without: Cannot find without on type string

I get the same error when I use:

{{- range $namespaces := .Values.namespaces }}
{{- if ne $namespaces.name "default" }}    
apiVersion: v1
kind: Namespace
metadata:
  name: {{ $namespaces.name }}
  labels:
    name: {{ $namespaces.name }}
{{ $custom := without $namespaces.name (list "default" "ingress-controller" "rbac-manager" "velero") }}
{{- if eq $custom.name }}
    namespace: custom
{{- end }}
---
{{- end }}
{{- end }}
-- bramvdk
go-templates
kubernetes-helm

Similar Questions

Make a request on all pods in Google Kubernetes
how to find my persistent volume location
Not able to connect to Elasticsearch in Docker
Incorrect HTTP method for uri 405 when trying to connect to ElasticSearch using Istio DNS name

2 Answers

5/27/2020

I know it is not really an answer on getting it to work with the without function, but I got it work with this:

{{ range $namespaces := .Values.namespaces }}
{{ if ne $namespaces.name "default" }}    
apiVersion: v1
kind: Namespace
metadata:
  name: {{ $namespaces.name }}
  labels:
    name: {{ $namespaces.name }}
{{ if (not (has $namespaces.name (list "default" "ingress-controller" "rbac-manager" "velero"))) }}
    namespace: custom
{{ end }}
{{ end }}
{{ end }}
-- bramvdk
Source: StackOverflow
5/27/2020

You are trying to pass a string as a first parameter to without function, while it requires a list.

Here's an example on how you can do it with without function. I removed redundant name key from namespaces array though.

values.yaml

namespaces:
  - default
  - ingress-controller
  - rbac-manager
  - velero
  - test1
  - test2
  - test3

namespace.yaml

{{ $compare := without .Values.namespaces list "default" "ingress-controller" "rbac-manager" "velero" }}
{{- range $namespace := .Values.namespaces }}
{{- if ne $namespace "default" }}    
apiVersion: v1
kind: Namespace
metadata:
  name: {{ $namespace }}
  labels:
    name: {{ $namespace }}
{{- if has $namespace $compare }}
    namespace: custom
{{- end }}
---
{{- end }}
{{- end }}

As withoutfunction is returning a list, first we create a list without specified values. Than we iterate over namespaces and check whether $custom list has the value or not.

-- edbighead
Source: StackOverflow