Method initFunMap

pkg/engine/helm/engine.go:204–269

initFunMap creates the Engine's FuncMap and adds context-specific functions.

(tmpl *template.Template)

// initFunMap creates the Engine's FuncMap and adds context-specific functions.
func (e Engine) initFunMap(tmpl *template.Template) {
	funcMap := funcMap()
	includedNames := make(map[string]int)

	// Add the template-rendering functions here so we can close over tmpl.
	funcMap[helmFuncInclude] = includeFun(tmpl, includedNames)
	funcMap[helmFuncTpl] = tplFun(tmpl, includedNames, e.Strict)

	// Add the `required` function here so we can use lintMode
	funcMap[helmFuncRequired] = func(warn string, val any) (any, error) {
		// A required value is considered missing when it is nil, or
		// when it is the empty string. Anything else passes through.
		missing := val == nil
		if !missing {
			if str, ok := val.(string); ok && str == "" {
				missing = true
			}
		}

		if !missing {
			return val, nil
		}

		if e.LintMode {
			// Don't fail on missing required values when linting
			log.Printf("[INFO] Missing required value: %s", warn)

			return "", nil
		}

		return val, errors.New(warnWrap(warn))
	}

	// Override sprig fail function for linting and wrapping message
	funcMap["fail"] = func(msg string) (string, error) {
		if e.LintMode {
			// Don't fail when linting
			log.Printf("[INFO] Fail: %s", msg)

			return "", nil
		}

		return "", errors.New(warnWrap(msg))
	}

	// If we are not linting and have a cluster connection, provide a Kubernetes-backed
	// implementation.
	if !e.LintMode {
		funcMap[helmFuncLookup] = LookupFunc
	}

	// When DNS lookups are not enabled override the sprig function and return
	// an empty string.
	if !e.EnableDNS {
		funcMap["getHostByName"] = func(_ string) string {
			return ""
		}
	}