Define a variable in Helm template

Question

I need to define a variable based on an if statement and use that variable multiple times. In order not to repeat the if I tried something like this:

{{ if condition}}
    {{ $my_val = "http" }}
{{ else }}
    {{ $my_val = "https" }}
{{ end }}
{{ $my_val }}://google.com

However this returns an error:

Error: render error in "templates/deployment.yaml":
template: templates/deployment.yaml:30:28:
executing "templates/deployment.yaml" at
<include (print $.Template.BasePath "/config.yaml") .>: error calling
include: template: templates/config.yaml:175:59:
executing "templates/config.yaml" at <"https">: undefined variable: $my_val

Ideas?

Answer 1

最直接的路径，这是使用ternary功能，由一枝库提供。那会让你写一些类似的东西

{{ $myVal := ternary "http" "https" condition -}}
{{ $myVal }}://google.com

一个更简单但更间接的路径是编写一个模板来生成值，并调用它

{{- define "scheme" -}}
{{- if condition }}http{{ else }}https{{ end }}
{{- end -}}

{{ template "scheme" . }}://google.com

如果您需要将 this 包含在另一个变量中，Helm 提供了一个include函数template，它的作用与此类似，只是它是一个“表达式”而不是直接输出的东西。

{{- $url := printf "%s://google.com" (include "scheme" .) -}}