feat: URL validation classes 'Url' and 'ReqUrl'

Closes #96

CHANGELOG.md

@@ -7,6 +7,11 @@ and this project adheres to [Dart Package Versioning](https://dart.dev/tools/pub
 
 ## [Unreleased]
 
+### Added
+
+- Url and ReqUrl classes to validate both optional and mandatory Url form fields
+  — [96](https://github.com/dartoos-dev/formdator/issues/96).
+
 ## [1.0.0] - 2022-01-09
 
 ### Added

README.md

@@ -29,9 +29,10 @@ alt="EO-Color logo" width="101" height="48"/>
 
 ## Overview
 
-**Form** Vali**dator** — Formdator is a fully object-oriented package for
-validating Flutter form fields. Its main benefits, compared to all other similar
-packages, include:
+**Formdator** — **Form**idable Vali**dator**.
+
+Formdator is a fully object-oriented package for validating Flutter form fields.
+Its main benefits, compared to all other similar packages, include:
 
 - **Dependency-free**: there is only pure Dart code.
 - **Object-oriented mindset**: the elements for validation are **immutable
@@ -138,7 +139,7 @@ Contributors are welcome!
    branch and make a _Pull Request_.
 3. After review and acceptance, the _Pull Request_ is merged and closed.
 
-Make sure the commands below **passes** before making a Pull Request.
+Make sure the command below **passes** before making a Pull Request.
 
 ```shell
   dart analyze && sudo dart test

analysis_options.yaml

@@ -9,6 +9,7 @@ analyzer:
     implicit-dynamic: false
 linter:
   rules:
+    always_use_package_imports: false
     # Make constructors the first thing in every class
     sort_constructors_first: true
     # Good packages document everything

example/pubspec.lock

@@ -42,14 +42,14 @@ packages:
       name: collection
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.15.0"
+    version: "1.16.0"
   fake_async:
     dependency: transitive
     description:
       name: fake_async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0"
+    version: "1.3.0"
   flutter:
     dependency: "direct main"
     description: flutter
@@ -66,7 +66,7 @@ packages:
       path: ".."
       relative: true
     source: path
-    version: "0.12.3"
+    version: "1.0.0"
   lint:
     dependency: "direct dev"
     description:
@@ -81,6 +81,13 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "0.12.11"
+  material_color_utilities:
+    dependency: transitive
+    description:
+      name: material_color_utilities
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.1.4"
   meta:
     dependency: transitive
     description:
@@ -94,7 +101,7 @@ packages:
       name: path
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0"
+    version: "1.8.1"
   sky_engine:
     dependency: transitive
     description: flutter
@@ -106,7 +113,7 @@ packages:
       name: source_span
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.1"
+    version: "1.8.2"
   stack_trace:
     dependency: transitive
     description:
@@ -141,20 +148,13 @@ packages:
       name: test_api
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.4.3"
-  typed_data:
-    dependency: transitive
-    description:
-      name: typed_data
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.3.0"
+    version: "0.4.9"
   vector_math:
     dependency: transitive
     description:
       name: vector_math
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.1"
+    version: "2.1.2"
 sdks:
-  dart: ">=2.15.0-7.0.dev <3.0.0"
+  dart: ">=2.17.0-0 <3.0.0"

lib/net.dart

@@ -11,3 +11,5 @@ export 'src/net/req_email.dart';
 export 'src/net/req_ipv4.dart';
 export 'src/net/req_ipv6.dart';
 export 'src/net/req_mac_addr.dart';
+export 'src/net/req_url.dart';
+export 'src/net/url.dart';

lib/src/net/req_url.dart

@@ -0,0 +1,16 @@
+import '../../core.dart';
+import '../../type.dart';
+import 'url.dart';
+
+/// Convenience validator for required URL values.
+class ReqUrl {
+  /// Non-blank and well-formed URL values.
+  ReqUrl({String blank = 'required URL', String mal = 'malformed URL'})
+      : _reqUrl = Pair.str2(Req(blank: blank), Url(mal: mal));
+
+  final ValObj _reqUrl;
+
+  /// Returns null if the value is a valid URL; otherwise it will return the
+  /// error message for blank fields or the error message for malformed fields.
+  String? call(String? value) => _reqUrl(value);
+}

lib/src/net/url.dart

@@ -0,0 +1,47 @@
+import 'package:formdator/formdator.dart';
+
+/// URL Validator.
+///
+/// Blank field - null value - is a valid input!
+///
+/// If the URL is required, see [ReqUrl] or [Req].
+///
+/// Notes on possible differences from a standard/generic validation:
+///
+/// - utf-8 char class take in consideration the full Unicode range
+/// - Top-level domains (TLDs) have been made mandatory so single names like
+///   "localhost" fails
+/// - protocols have been restricted to ftp, http and https
+/// - IP address dotted notation validation, range: 1.0.0.0 - 223.255.255.255
+///   first and last IP address of each class is considered invalid (since they
+///   are broadcast/network addresses)
+///
+/// - Made starting path slash optional (http://example.com?foo=bar)
+/// - Allow a dot (.) at the end of hostnames (http://example.com.)
+/// - Allow an underscore (_) character in host/domain_names
+/// - Check dot delimited parts length and total length
+/// - Made protocol optional, allowed short syntax //
+class Url {
+  /// Validates URL values using a regular expression.
+  ///
+  /// If the URL field is mandatory, see [ReqUrl] or [Req].
+  const Url({this.mal = 'malformed URL'});
+
+  /// The error message in case of a malformed URL value.
+  final String mal;
+
+  /// A suitable pattern for  URL values.
+  ///
+  /// Reference: [gist](https://gist.github.com/dperini/729294)
+  static final RegExp urlPattern = RegExp(
+    r'^(?:(?:(?:https?|ftp):)?\/\/)(?:\S+(?::\S*)?@)?(?:(?:[1-9]\d?|1\d\d|2[01]\d|22[0-3])(?:\.(?:1?\d{1,2}|2[0-4]\d|25[0-5])){2}(?:\.(?:[1-9]\d?|1\d\d|2[0-4]\d|25[0-4]))|(?:(?:[a-z0-9\u00a1-\uffff][a-z0-9\u00a1-\uffff_-]{0,62})?[a-z0-9\u00a1-\uffff]\.)+(?:[a-z\u00a1-\uffff]{2,}\.?))(?::\d{2,5})?(?:[/?#]\S*)?$',
+    caseSensitive: false,
+    unicode: true,
+  );
+
+  /// Returns `null` if [value] is `null` or a valid URL; returns [mal]
+  /// otherwise.
+  String? call(String? value) {
+    return value == null || urlPattern.hasMatch(value) ? null : mal;
+  }
+}

test/net/req_url_test.dart

@@ -0,0 +1,22 @@
+import 'package:formdator/src/net/req_url.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group('ReqUrl', () {
+    const blank = 'required URL value';
+    const mal = 'malformed URL value';
+    final reqUrl = ReqUrl(blank: blank, mal: mal);
+    test('null - blank', () {
+      expect(reqUrl(null), blank);
+    });
+    test('empty - blank', () {
+      expect(reqUrl(''), blank);
+    });
+    test('valid URL', () {
+      expect(reqUrl('http://10.0.1.1'), null);
+    });
+    test('invalid URL', () {
+      expect(reqUrl('http://10.10.10.256'), mal);
+    });
+  });
+}

test/net/url_test.dart

@@ -0,0 +1,75 @@
+import 'package:formdator/src/net/url.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group('URL', () {
+    const error = 'malformed URL value';
+    const url = Url(mal: error);
+    test('Valid Urls:', () {
+      expect(url(null), null);
+      expect(url('//shortsyntax.com'), null);
+      expect(url('//www.shortsyntax.com'), null);
+      expect(url('http://www.example.com'), null);
+      expect(url('http://www.example.com.'), null);
+      expect(url('http://www.example.com/index.html'), null);
+      expect(url('http://example.com?foo=bar'), null);
+      expect(url('https://www.example.com/foo/?bar=baz&inga=42&quux'), null);
+      expect(url('http://odf.ws/123'), null);
+      expect(url('http://userid:[email protected]:8080'), null);
+      expect(url('http://userid:[email protected]:8080/'), null);
+      expect(url('https://www.youtube.com/watch?v=nmhX3_m84Is'), null);
+      expect(url('http://foo.com/blah_blah#cite-1'), null);
+      expect(url('http://[email protected]:8080/'), null);
+      expect(url('http://foo.com/blah_(wikipedia)#cite-1'), null);
+      expect(url('http://foo.com/blah_(wikipedia)_blah#cite-1'), null);
+      expect(url('http://code.google.com/events/#&product=browser'), null);
+      expect(url('http://foo.bar/?q=Test%20URL-encoded%20stuff'), null);
+      expect(url("http://-.~_!&'()*+,;=:%40:80%2f::::::@example.com"), null);
+      expect(url('https://foo_bar.example.com/'), null);
+      expect(url('http://1337.net'), null);
+      expect(url('http://192.168.0.3'), null);
+      expect(url('http://192.168.0.3/resource'), null);
+      expect(url('http://223.255.255.254'), null);
+    });
+    test('Valid FTP Urls:', () {
+      expect(url('ftp://example.com'), null);
+      expect(url('ftp://example.com:8080'), null);
+      expect(url('ftp://example.com:8080/'), null);
+      expect(url('ftp://example.com:8080/url-path'), null);
+      expect(url('ftp://userid:[email protected]:8080/url-path'), null);
+    });
+    test('invalid URLs', () {
+      expect(url(''), error);
+      expect(url('//'), error);
+      expect(url('://'), error);
+      expect(url('//a'), error);
+      expect(url('http://'), error);
+      expect(url('http:///a'), error);
+      expect(url('foo.com'), error);
+      expect(url('rdar://1234'), error);
+      expect(url('http://.'), error);
+      expect(url('http://..'), error);
+      expect(url('http://?'), error);
+      expect(url('http://??'), error);
+      expect(url('http://#'), error);
+      expect(url('http://##'), error);
+      expect(url('1'), error);
+      expect(url('10.10'), error);
+      expect(url('0.0.0.0'), error);
+      expect(url('http://10.1.1.255'), error);
+      expect(url('http://224.1.1.1'), error);
+      expect(url('http://3628126748'), error);
+      // the first IP andress (network) of each class is considered invalid.
+      expect(url('http://192.168.0.0'), error);
+      expect(url('http://192.168.0.0/resource'), error);
+      // the last IP andress (broadcast) of each class is considered invalid.
+      expect(url('http://192.168.0.255/'), error);
+      expect(url('http://192.168.0.255/resource'), error);
+
+      expect(url('http://?df.ws/123'), error);
+      expect(url('http:// shouldfail.com'), error);
+      expect(url('http://.www.foo.bar/'), error);
+      expect(url('http://foo.bar?q=Spaces should be encoded'), error);
+    });
+  });
+}