I have the following yaml

items:
   - itemName: a
     awesome: true
   - itemName: b
   - itemName: c
     awesome: false

I need a function that gets a as an output, since item a has the attribute awesome == true. How do I do that?

Approach that does not work:

{{- $result := "nope" }}
{{- range $i := $items }}
  {{- if and (and (hasKey $i. awesome) ($i.awesome)) !($result -eq "nope") }}
    {{- $result := $i.itemName }}
  {{- end }}
{{- end }}

Have not tried the above approach, but am confident that this does not work (see this post). What I'd need is a default function that works for lists. I could not find any in sprig. Any Idea?

CodePudding user response：

The linked post, based on which you claim you know that the code doesn't work, does not, in the question snippet, pre-declare the variable.

In your code you do pre-declare the variable but you are making a different error. The error is that you are using := to assign the value to the pre-declared variable, however := in templates works the same as in Go itself, it initializes a new variable. You need to use = for assignment to an existing variable.

https://pkg.go.dev/text/[email protected]#hdr-Variables

A pipeline inside an action may initialize a variable to capture the result. The initialization has syntax

$variable := pipeline

where $variable is the name of the variable. An action that declares a variable produces no output.

Variables previously declared can also be assigned, using the syntax

$variable = pipeline

So all you need to do is to change {{- $result := $i.itemName }} to {{- $result = $i.itemName }}.

{{- $result := "nope" }}
{{- range $i := $items }}
  {{- if and (and (hasKey $i. awesome) ($i.awesome)) !($result -eq "nope") }}
    {{- $result = $i.itemName }}
  {{- end }}
{{- end }}

An example to prove this is working: https://play.golang.org/p/A44yl7jo0v7