jsonnet cli invocation?

[strowi]

Hi,

after experimenting a lot with tanka, helm-charts and k8s, i stumbled across a (probably) small problem.
Shouldn't i be able to run sth. like jsonnet -J lib -J vendor environments/demo/main.jsonnet for jsonnet cli to generate the same output?
Instead i am getting an error probably related to the helm-chart lib, even though tanka itself works flawless.;)

~> jsonnet -J lib -J vendor environments/demo/main.jsonnet
RUNTIME ERROR: Unexpected type null, expected function
	vendor/github.com/grafana/jsonnet-libs/tanka-util/helm.libsonnet:46:23-67	thunk <chartData> from <function <anonymous>>
	vendor/github.com/grafana/jsonnet-libs/tanka-util/helm.libsonnet:48:21-30	thunk from <function <anonymous>>
	vendor/github.com/grafana/jsonnet-libs/tanka-util/k8s.libsonnet:43:7-13	thunk from <function <anonymous>>
	vendor/github.com/grafana/jsonnet-libs/tanka-util/k8s.libsonnet:13:21-27	thunk from <function <anonymous>>
	<std>:31:26-27	thunk from <function <anonymous>>
	<std>:31:17-28	function <anonymous>
	vendor/github.com/grafana/jsonnet-libs/tanka-util/k8s.libsonnet:13:8-28	function <anonymous>
	vendor/github.com/grafana/jsonnet-libs/tanka-util/k8s.libsonnet:(42:5)-(49:6)	function <anonymous>
	vendor/github.com/grafana/jsonnet-libs/tanka-util/helm.libsonnet:48:5-51	function <anonymous>
	lib/emqx/main.jsonnet:(11:12)-(92:6)	object <anonymous>
	Field "chart"	
	Field "emqx"	
	During manifestation

regards,
strowi

[julienduchesne]

tanka-util has a Tanka function being used (helmTemplate): https://github.com/grafana/jsonnet-libs/blob/master/tanka-util/helm.libsonnet#L46

It's defined here:

tanka/pkg/helm/jsonnet.go

Lines 34 to 79 in c5a739e

	func NativeFunc(h Helm) *jsonnet.NativeFunction {
	return &jsonnet.NativeFunction{
	Name: "helmTemplate",
	// Similar to `helm template [NAME] [CHART] [flags]` except 'conf' is a
	// bit more elaborate and chart is a local path
	Params: ast.Identifiers{"name", "chart", "opts"},
	Func: func(data []interface{}) (interface{}, error) {
	name, ok := data[0].(string)
	if !ok {
	return nil, fmt.Errorf("first argument 'name' must be of 'string' type, got '%T' instead", data[0])
	}
	chartpath, ok := data[1].(string)
	if !ok {
	return nil, fmt.Errorf("second argument 'chart' must be of 'string' type, got '%T' instead", data[1])
	}
	// TODO: validate data[2] actually follows the struct scheme
	opts, err := parseOpts(data[2])
	if err != nil {
	return "", err
	}
	// resolve the Chart relative to the caller
	callerDir := filepath.Dir(opts.CalledFrom)
	chart := filepath.Join(callerDir, chartpath)
	if _, err := os.Stat(chart); err != nil {
	return nil, fmt.Errorf("helmTemplate: Failed to find a chart at '%s': %s. See https://tanka.dev/helm#failed-to-find-chart", chart, err)
	}
	// render resources
	list, err := h.Template(name, chart, opts.TemplateOpts)
	if err != nil {
	return nil, err
	}
	// convert list to map
	out, err := manifest.ListAsMap(list, opts.NameFormat)
	if err != nil {
	return nil, err
	}
	return out, nil
	},
	}
	}