platform/lib/src/strategies/local.dart
2018-07-12 13:11:54 -04:00

102 lines
3.2 KiB
Dart

import 'dart:async';
import 'package:dart2_constant/convert.dart';
import 'package:angel_framework/angel_framework.dart';
import '../options.dart';
import '../strategy.dart';
bool _validateString(String str) => str != null && str.isNotEmpty;
/// Determines the validity of an incoming username and password.
typedef Future LocalAuthVerifier(String username, String password);
class LocalAuthStrategy extends AuthStrategy {
RegExp _rgxBasic = new RegExp(r'^Basic (.+)$', caseSensitive: false);
RegExp _rgxUsrPass = new RegExp(r'^([^:]+):(.+)$');
@override
String name = 'local';
LocalAuthVerifier verifier;
String usernameField;
String passwordField;
String invalidMessage;
final bool allowBasic;
final bool forceBasic;
String realm;
LocalAuthStrategy(LocalAuthVerifier this.verifier,
{String this.usernameField: 'username',
String this.passwordField: 'password',
String this.invalidMessage:
'Please provide a valid username and password.',
bool this.allowBasic: true,
bool this.forceBasic: false,
String this.realm: 'Authentication is required.'}) {}
@override
Future<bool> canLogout(RequestContext req, ResponseContext res) async {
return true;
}
@override
Future authenticate(RequestContext req, ResponseContext res,
[AngelAuthOptions options_]) async {
AngelAuthOptions options = options_ ?? new AngelAuthOptions();
var verificationResult;
if (allowBasic) {
String authHeader = req.headers.value('authorization') ?? "";
if (_rgxBasic.hasMatch(authHeader)) {
String base64AuthString = _rgxBasic.firstMatch(authHeader).group(1);
String authString =
new String.fromCharCodes(base64.decode(base64AuthString));
if (_rgxUsrPass.hasMatch(authString)) {
Match usrPassMatch = _rgxUsrPass.firstMatch(authString);
verificationResult =
await verifier(usrPassMatch.group(1), usrPassMatch.group(2));
} else
throw new AngelHttpException.badRequest(errors: [invalidMessage]);
if (verificationResult == false || verificationResult == null) {
res
..statusCode = 401
..headers['www-authenticate'] = 'Basic realm="$realm"'
..end();
return false;
}
return verificationResult;
}
}
if (verificationResult == null) {
await req.parse();
if (_validateString(req.body[usernameField]?.toString()) &&
_validateString(req.body[passwordField]?.toString())) {
verificationResult = await verifier(req.body[usernameField]?.toString(),
req.body[passwordField]?.toString());
}
}
if (verificationResult == false || verificationResult == null) {
if (options.failureRedirect != null &&
options.failureRedirect.isNotEmpty) {
res.redirect(options.failureRedirect, code: 401);
return false;
}
if (forceBasic) {
res
..statusCode = 401
..headers['www-authenticate'] = 'Basic realm="$realm"'
..end();
}
return false;
} else if (verificationResult != null && verificationResult != false) {
return verificationResult;
} else {
throw new AngelHttpException.notAuthenticated();
}
}
}