Csrf.origin constructor
Creates a CSRF middleware that validates against a single origin.
Example:
app.use(Csrf.origin('https://example.com'));
Implementation
factory Csrf.origin(
String origin, {
String errorMessage = 'Potential CSRF attack detected',
}) {
return Csrf._(
originValidator: (o, _) => o == origin,
errorMessage: errorMessage,
);
}