template.go

package validation

import "strings"

// TemplateParameter is injected into the message while rendering the template.
type TemplateParameter struct {
	// Key is the marker in the string that will be replaced by value.
	// In general, it is recommended to use double curly braces around the key name.
	// Example: {{ keyName }}
	Key string

	// Value is set by constraint when building violation.
	Value string

	// NeedsTranslation marks that the template value needs to be translated.
	NeedsTranslation bool
}

// TemplateParameterList is a list of template parameters that can be injection into violation message.
type TemplateParameterList []TemplateParameter

// Prepend returns [TemplateParameterList] prepended by given parameters.
func (params TemplateParameterList) Prepend(parameters ...TemplateParameter) TemplateParameterList {
	return append(parameters, params...)
}

func renderMessage(template string, parameters []TemplateParameter) string {
	message := template

	for _, p := range parameters {
		message = strings.ReplaceAll(message, p.Key, p.Value)
	}

	return message
}