0.0.1

README.md

@@ -17,8 +17,11 @@ For convenience's sake, this library also exports `matcher`.
   * [Creating a Validator](#creating-a-validator)
   * [Validating Data](#validating-data)
   * [Required Fields](#required-fields)
+  * [Forbidden Fields](#forbidden-fields)
   * [Default Values](#default-values)
   * [Custom Validator Functions](#custom-validator-functions)
+* [Auto-parsing Numbers](#autoparse)
+* [Custom Error Messages](#custom-error-messages)
 * [Extending Validators](#extending-validators)
 * [Bundled Matchers](#bundled-matchers)
 * [Nested Validators](#nested-validators)
@@ -88,6 +91,10 @@ main() {
 }
 ```
 
+## Forbidden Fields
+To prevent a field from showing up in valid data, suffix it
+with a `'!'`.
+
 
 ## Default values
 
@@ -127,10 +134,39 @@ main() {
 }
 ```
 
+# Custom Error Messages
+If these are not present, `angel_validate` will *attempt* to generate
+a coherent error message on its own.
+
+```dart
+new Validator({
+    'age': [greaterThanOrEqualTo(18)]
+}, customErrorMessages: {
+    'age': 'You must be an adult to see this page.'
+});
+```
+
+# autoParse
+Oftentimes, fields that we want to validate as numbers are passed as strings.
+Calling `autoParse` will correct this before validation.
+
+```dart
+main() {
+    var parsed = autoParse({
+        'age': '34',
+        'weight': '135.6'
+    }, ['age', 'weight']);
+
+    validator.enforce(parsed);
+}
+```
+
+You can also call `checkParsed` or `enforceParsed` as a shorthand.
+
 # Extending Validators
 You can add situation-specific rules within a child validator.
-You can also use `extend` to mark fields as required that originally
+You can also use `extend` to mark fields as required or forbidden that originally
-were not. Default value extension is also supported.
+were not. Default value and custom error message extension is also supported.
 
 ```dart
 final Validator userValidator = new Validator({
@@ -170,12 +206,12 @@ register(Map userData) {
 This library includes some `Matcher`s for common validations,
 including:
 
-* `isAlphaDash`: Asserts a `String` matches the Regular Expression ```/^[A-Za-z0-9_-]$/```.
+* `isAlphaDash`: Asserts that a `String` is alphanumeric, but also lets it contain dashes or underscores.
-* `isAlphaNum`: Asserts a `String` matches the Regular Expression ```/^[A-Za-z0-9]$/```
+* `isAlphaNum`: Asserts that a `String` is alphanumeric.
 * `isBool`: Asserts that a value either equals `true` or `false`.
-* `isEmail`: Asserts a `String` complies to the RFC 5322 e-mail standard.
+* `isEmail`: Asserts that a `String` complies to the RFC 5322 e-mail standard.
-* `isInt`: Asserts a value is an `int`.
+* `isInt`: Asserts that a value is an `int`.
-* `isNum`: Asserts a value is a `num`.
+* `isNum`: Asserts that a value is a `num`.
 * `isString`: Asserts that a value is a `String`.
 
 The remaining functionality is
@@ -218,10 +254,12 @@ main() {
 
 # Use with Angel
 
-`server.dart` exposes three helper middleware:
+`server.dart` exposes five helper middleware:
 * `validate(validator)`: Validates and filters `req.body`, and throws an `AngelHttpException.BadRequest` if data is invalid.
 * `validateEvent(validator)`: Sets `e.data` to the result of validation on a service event.
-* `validateQuery(validator)`: Same as `validate`, but operates `req.query`.
+* `validateQuery(validator)`: Same as `validate`, but operates on `req.query`.
+* `autoParseBody(fields)`: Auto-parses numbers in `req.body`.
+* `autoParseQuery(fields)`: Same as `autoParseBody`, but operates on `req.query`.
 
 ```dart
 import 'package:angel_framework/angel_framework.dart';

lib/server.dart

@@ -5,6 +5,22 @@ import 'package:angel_framework/angel_framework.dart';
 import 'angel_validate.dart';
 export 'angel_validate.dart';
 
+/// Auto-parses numbers in `req.body`.
+RequestMiddleware autoParseBody(List<String> fields) {
+  return (RequestContext req, res) async {
+    req.body.addAll(autoParse(req.body, fields));
+    return true;
+  };
+}
+
+/// Auto-parses numbers in `req.query`.
+RequestMiddleware autoParseQuery(List<String> fields) {
+  return (RequestContext req, res) async {
+    req.query.addAll(autoParse(req.query, fields));
+    return true;
+  };
+}
+
 /// Validates the data in `req.body`, and sets the body to
 /// filtered data before continuing the response.
 RequestMiddleware validate(Validator validator,

lib/src/matchers.dart

@@ -1,13 +1,31 @@
 import 'package:matcher/matcher.dart';
 
+final RegExp _alphaDash = new RegExp(r'^[A-Za-z0-9_-]+$');
+final RegExp _alphaNum = new RegExp(r'^[A-Za-z0-9]+$');
+final RegExp _email = new RegExp(
+    r"^[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?$");
+
+/// Asserts that a `String` is alphanumeric, but also lets it contain dashes or underscores.
+final Matcher isAlphaDash = predicate(
+    (value) => value is String && _alphaDash.hasMatch(value),
+    'alphanumeric (dashes and underscores are allowed) ');
+
+/// Asserts that a `String` is alphanumeric, but also lets it contain dashes or underscores.
+final Matcher isAlphaNum = predicate(
+    (value) => value is String && _alphaNum.hasMatch(value), 'alphanumeric ');
+
 /// Asserts that a value either equals `true` or `false`.
-final Matcher isBool = predicate((value) => value is String, 'a bool ');
+final Matcher isBool = predicate((value) => value is bool, 'a bool ');
+
+///  Asserts that a `String` complies to the RFC 5322 e-mail standard.
+final Matcher isEmail = predicate(
+    (value) => value is String && _email.hasMatch(value), 'a valid e-mail ');
 
 /// Asserts that a value is an `int`.
-final Matcher isInt = predicate((value) => value is String, 'an integer ');
+final Matcher isInt = predicate((value) => value is int, 'an integer ');
 
 /// Asserts that a value is a `num`.
-final Matcher isNumber = predicate((value) => value is String, 'a number ');
+final Matcher isNum = predicate((value) => value is num, 'a number ');
 
 /// Asserts that a value is a `String`.
 final Matcher isString = predicate((value) => value is String, 'a String ');

lib/src/validator.dart

@@ -1,6 +1,7 @@
 import 'package:matcher/matcher.dart';
 
 final RegExp _asterisk = new RegExp(r'\*$');
+final RegExp _forbidden = new RegExp(r'\!$');
 final RegExp _optional = new RegExp(r'\?$');
 
 /// Returns a value based the result of a computation.
@@ -9,11 +10,37 @@ typedef DefaultValueFunction();
 /// Determines if a value is valid.
 typedef bool Filter(value);
 
+/// Converts the desired fields to their numeric representations, if present.
+Map<String, dynamic> autoParse(Map inputData, List<String> fields) {
+  Map<String, dynamic> data = {};
+
+  for (var key in inputData.keys) {
+    if (!fields.contains(key)) {
+      data[key] = inputData[key];
+    } else {
+      try {
+        var n = num.parse(inputData[key].toString());
+        data[key] = n == n.toInt() ? n.toInt() : n;
+      } catch (e) {
+        // Invalid number, don't pass it
+      }
+    }
+  }
+
+  return data;
+}
+
 /// Enforces the validity of input data, according to [Matcher]s.
 class Validator extends Matcher {
+  /// Pre-defined error messages for certain fields.
+  final Map<String, String> customErrorMessages = {};
+
   /// Values that will be filled for fields if they are not present.
   final Map<String, dynamic> defaultValues = {};
 
+  /// Fields that cannot be present in valid data.
+  final List<String> forbiddenFields = [];
+
   /// Conditions that must be met for input data to be considered valid.
   final Map<String, List<Matcher>> rules = {};
 
@@ -22,10 +49,16 @@ class Validator extends Matcher {
 
   void _importSchema(Map<String, dynamic> schema) {
     for (var key in schema.keys) {
-      var fieldName = key.replaceAll(_asterisk, '');
+      var fieldName = key
-      var isRequired = _asterisk.hasMatch(key);
+          .replaceAll(_asterisk, '')
+          .replaceAll(_forbidden, '')
+          .replaceAll(_optional, '');
+      var isForbidden = _forbidden.hasMatch(key),
+          isRequired = _asterisk.hasMatch(key);
 
-      if (isRequired) {
+      if (isForbidden) {
+        forbiddenFields.add(fieldName);
+      } else if (isRequired) {
         requiredFields.add(fieldName);
       }
 
@@ -47,8 +80,10 @@ class Validator extends Matcher {
   Validator.empty();
 
   Validator(Map<String, dynamic> schema,
-      {Map<String, dynamic> defaultValues: const {}}) {
+      {Map<String, dynamic> defaultValues: const {},
+      Map<String, dynamic> customErrorMessages: const {}}) {
     this.defaultValues.addAll(defaultValues ?? {});
+    this.customErrorMessages.addAll(customErrorMessages ?? {});
     _importSchema(schema);
   }
 
@@ -65,9 +100,21 @@ class Validator extends Matcher {
       }
     }
 
+    for (String field in forbiddenFields) {
+      if (input.containsKey(field)) {
+        if (!customErrorMessages.containsKey(field))
+          errors.add("'$field' is forbidden.");
+        else
+          errors.add(customErrorMessages[field]);
+      }
+    }
+
     for (String field in requiredFields) {
       if (!input.containsKey(field)) {
+        if (!customErrorMessages.containsKey(field))
           errors.add("'$field' is required.");
+        else
+          errors.add(customErrorMessages[field]);
       }
     }
 
@@ -88,6 +135,7 @@ class Validator extends Matcher {
               }
             } else {
               if (!matcher.matches(value, {})) {
+                if (!customErrorMessages.containsKey(key))
                   errors.add(matcher.describe(description).toString().trim());
                 valid = false;
               }
@@ -100,6 +148,8 @@ class Validator extends Matcher {
 
         if (valid) {
           data[key] = value;
+        } else if (customErrorMessages.containsKey(key)) {
+          errors.add(customErrorMessages[key]);
         }
       }
     }
@@ -111,6 +161,10 @@ class Validator extends Matcher {
     return new ValidationResult().._data = data;
   }
 
+  /// Validates, and filters input data after running [autoParse].
+  ValidationResult checkParsed(Map inputData, List<String> fields) =>
+      check(autoParse(inputData, fields));
+
   /// Validates input data, and throws an error if it is invalid.
   ///
   /// Otherwise, the filtered data is returned.
@@ -127,41 +181,47 @@ class Validator extends Matcher {
 
   /// Creates a copy with additional validation rules.
   Validator extend(Map<String, dynamic> schema,
-      {Map<String, dynamic> defaultValues: const {}, bool overwrite: false}) {
+      {Map<String, dynamic> defaultValues: const {},
+      Map<String, String> customErrorMessages: const {},
+      bool overwrite: false}) {
     Map<String, dynamic> _schema = {};
     var child = new Validator.empty()
       ..defaultValues.addAll(this.defaultValues)
       ..defaultValues.addAll(defaultValues ?? {})
+      ..customErrorMessages.addAll(this.customErrorMessages)
+      ..customErrorMessages.addAll(customErrorMessages ?? {})
       ..requiredFields.addAll(requiredFields)
       ..rules.addAll(rules);
 
+    for (var key in schema.keys) {
+      var fieldName = key
+          .replaceAll(_asterisk, '')
+          .replaceAll(_forbidden, '')
+          .replaceAll(_optional, '');
+      var isForbidden = _forbidden.hasMatch(key);
+      var isOptional = _optional.hasMatch(key);
+      var isRequired = _asterisk.hasMatch(key);
+
+      if (isForbidden) {
+        child
+          ..requiredFields.remove(fieldName)
+          ..forbiddenFields.add(fieldName);
+      } else if (isOptional) {
+        child
+          ..forbiddenFields.remove(fieldName)
+          ..requiredFields.remove(fieldName);
+      } else if (isRequired) {
+        child
+          ..forbiddenFields.remove(fieldName)
+          ..requiredFields.add(fieldName);
+      }
+
       if (overwrite) {
-      for (var key in schema.keys) {
+        if (child.rules.containsKey(fieldName)) child.rules.remove(fieldName);
-        var fieldName = key.replaceAll(_asterisk, '').replaceAll(_optional, '');
+      }
-        var isOptional = _optional.hasMatch(key);
-        var isRequired = _asterisk.hasMatch(key);
-
-        if (isOptional)
-          child.requiredFields.remove(fieldName);
-        else if (isRequired) child.requiredFields.add(fieldName);
-
-        if (child.rules.containsKey(key)) child.rules.remove(key);
 
       _schema[fieldName] = schema[key];
     }
-    } else {
-      for (var key in schema.keys) {
-        var fieldName = key.replaceAll(_asterisk, '').replaceAll(_optional, '');
-        var isOptional = _optional.hasMatch(key);
-        var isRequired = _asterisk.hasMatch(key);
-
-        if (isOptional)
-          child.requiredFields.remove(fieldName);
-        else if (isRequired) child.requiredFields.add(fieldName);
-
-        _schema[fieldName] = schema[key];
-      }
-    }
 
     return child.._importSchema(_schema);
   }

pubspec.yaml

@@ -1,6 +1,6 @@
 name: angel_validate
 description: Cross-platform validation library based on `matcher`.
-version: 0.0.0
+version: 0.0.1
 author: Tobe O <thosakwe@gmail.com>
 homepage: https://github.com/angel-dart/validate
 environment:

test/basic_test.dart

@@ -1,6 +1,12 @@
 import 'package:angel_validate/angel_validate.dart';
 import 'package:test/test.dart';
 
+final Validator emailSchema = new Validator({
+  'to': [isNum, isPositive]
+}, customErrorMessages: {
+  'to': 'Hello, world!'
+});
+
 final Validator todoSchema = new Validator({
   'id': [isInt, isPositive],
   'text*': isString,
@@ -10,6 +16,14 @@ final Validator todoSchema = new Validator({
 });
 
 main() {
+  test('custom error message', () {
+    var result = emailSchema.check({'to': 2});
+
+    expect(result.errors, isList);
+    expect(result.errors, hasLength(1));
+    expect(result.errors.first, equals('Hello, world!'));
+  });
+
   test('todo', () {
     expect(() {
       todoSchema