in src/main/java/software/amazon/cloudformation/resource/BaseValidator.java [92:108]
void registerMetaSchema(final SchemaLoaderBuilder loaderBuilder, JSONObject schema) {
try {
final String id;
if (schema.has(ID_KEY)) {
id = schema.getString(ID_KEY);
if (id.isEmpty()) {
throw new ValidationException("Invalid $id value", "$id", "[empty string]");
}
final URI uri = new URI(id);
loaderBuilder.registerSchemaByURI(uri, schema);
}
} catch (URISyntaxException | JSONException e) {
// $id is not a string or URI is invalid
throw new ValidationException("Invalid $id value", "$id", e);
}
}