Introduction #
Usage #
Use the safe.JS function to encapsulate a known safe EcmaScript5 Expression.
Template authors are responsible for ensuring that typed expressions do not break the intended precedence and that there is no statement/expression ambiguity as when passing an expression like { foo: bar() }\n['foo'](), which is both a valid Expression and a valid Program with a very different meaning.
Use of this type presents a security risk: the encapsulated content should come from a trusted source, as it will be included verbatim in the template output.
Using the safe.JS function to include valid but untrusted JSON is not safe. A safe alternative is to parse the JSON with the [transform.Unmarshal] function and then pass the resultant object into the template, where it will be converted to sanitized JSON when presented in a JavaScript context.
See the [Go documentation] for details.
Example #
Without a safe declaration:
{{ $js := "x + y" }}
<script>const a = {{ $js }}</script>
Hugo renders the above to:
<script>const a = "x + y"</script>
To declare the string as safe:
{{ $js := "x + y" }}
<script>const a = {{ $js | safeJS }}</script>
Hugo renders the above to:
<script>const a = x + y</script>