Templating

In most cases, if a test file ends with .gotmpl.yaml, then it will be treated as a Go text/template for expansion, before it is parsed as YAML.

The data structure available to templates is defined as follows:

type Env struct {
	// Name of the namespace for the test.
	Namespace string
	// Any variables defined when invoking `kuttl test`
	// with --template-var name=value
	// Note that each value is parsed as YAML, so you can
	// pass the usual data structures as variables.
	Vars map[string]any
}

As of kuttl version 0.25, the sprig functions are also available.

Example

Let's take the following test suite:

suite1/
└── test1
    ├── 00-apply.gotmpl.yaml
    └── 00-assert.gotmpl.yaml

• 00-apply.gotmpl.yaml:

apiVersion: v1
kind: Pod
metadata:
  name: foo-{{ .Namespace }}-foo-{{ .Vars.var2 }}-baz
spec:
  containers:
    - name: foo
      image: foo

• 00-assert.gotmpl.yaml:

apiVersion: v1
kind: Pod
metadata:
  name: foo-{{ .Namespace }}-{{ .Vars.var1 }}-bar-{{ .Vars.var3 }}

Then, one can invoke kuttl test --template-var var1=foo --template-var var2=bar,var3=baz suite1 and see the following as expected:

=== CONT  kuttl/harness/test1
    logger.go:42: 12:06:57 | test1 | Creating namespace "kuttl-test-trusted-mackerel"
    logger.go:42: 12:06:57 | test1/0-apply | starting test step 0-apply
    logger.go:42: 12:06:57 | test1/0-apply | Pod:kuttl-test-trusted-mackerel/foo-kuttl-test-trusted-mackerel-foo-bar-baz created
    logger.go:42: 12:06:57 | test1/0-apply | test step completed 0-apply
    logger.go:42: 12:06:57 | test1 | test1 events from ns kuttl-test-trusted-mackerel:
[...]
--- PASS: kuttl (6.43s)
    --- PASS: kuttl/harness (0.00s)
        --- PASS: kuttl/harness/test1 (0.04s)
PASS

Exceptions

The places where template expansion is currently not available are when loading:

• resources from a suite's manifestDirs and crdDir
• top-level kutt-test.yaml config file
• files by the kuttl assert and kuttl errors commands (as opposed to kuttl test)
• files listed in the apply, assert and error fields of a TestStep resource

The above cases may be supported in a future version.