I use Jackson to generate JSON objects and write them directly into HTML's tag, like this:
<script>
var data = $SomeJacksonWrapper.toJson($data);
</script>
This code breaks if some string contains '</script>' in it. Escaping forward slash (/) would solve the problem and it is alowed by JSON's spec.
How do I enable it in Jackson?
Kotlin version of a custom character escape for forward slashes:
/**
* Behaves like PHP json_encode() in that forward slashes are escaped.
*/
private class PhpCompatJsonEncode : CharacterEscapes() {
private val delegate = JsonpCharacterEscapes()
private val escapeForSlash = SerializedString("\\/")
private val asciiEscapes = standardAsciiEscapesForJSON()
init {
asciiEscapes['/'.code] = ESCAPE_CUSTOM
}
override fun getEscapeCodesForAscii(): IntArray {
return asciiEscapes
}
override fun getEscapeSequence(ch: Int): SerializableString? {
return when (ch) {
'/'.code -> escapeForSlash
else -> delegate.getEscapeSequence(ch)
}
}
}
This can also be configured per-writer, instead of globally in case this is only needed at a specific spot:
val writer: ObjectWriter = objectMapper.writer(PhpCompatJsonEncode())