drails_validator 0.1.0

Library for validate models similar to JPA Bean validation.

drails_validator

Library for validate models similar to JPA Bean validation. It provides a way to validate a dart object using constraints which we can use for validation.

To check if the object is valid we need to invoke the function validate. This one returns an Object of type ValidationResult which contains a map of errors for every attribute of the object, for example:

1. Create a new dart project

2. Add dependencies to pubspec.yaml

...
dependencies:
  ...
  drails_validator: ^0.1.0 #change it for the latest version
  ...

3.Create/edit the file main.dart in the folder bin and put next code on it:

// Copyright (c) 2015, Luis Vargas. All rights reserved. Use of this source code
// is governed by a BSD-style license that can be found in the LICENSE file.

library Validator.example;

import 'package:validator/validator.dart' as validator;
import 'package:drails_validator/drails_validator.dart';

part 'drails_validator_sample.g.dart';

bool lowerThanOrEqualNow(DateTime dateOfBirth) =>
  !dateOfBirth.isAfter(new DateTime.now());

bool isSSN(String ssn) =>
  validator.matches(ssn, r'\d\d\d-\d\d-\d\d\d\d');

bool isEmail(String email) =>
    isNotNull(email) && validator.isEmail(email);

@serializable
class Person extends _$PersonSerializable {
  int id;
  
  @Length(min: 2)
  String firstName;
  
  @Length(min: 2)
  String lastName;
  
  @ValidIf(isEmail, customDescription: 'The entered email is invalid')
  String email;
  
  @ValidIf(lowerThanOrEqualNow, customDescription: 'Values after now are not allowed')
  DateTime dateOfBirth;
  
  @ValidIf(isSSN, customDescription: 'The entered SSN is invalid')
  String ssn;
}

main() {
  _initMirrors();

  var invalidPerson = new Person()
        ..id = 1
        ..firstName = ''
        ..lastName = ''
        ..dateOfBirth = new DateTime(2030, 11, 9)
        ..ssn = '123',
      validPerson = new Person()
        ..id = 2
        ..firstName = 'Joe'
        ..lastName = 'Doe'
        ..email = '[e-mail]'
        ..dateOfBirth = new DateTime(1989, 11, 9)
        ..ssn = '123-45-6789';

  print('invalidPerson: ${validate(invalidPerson)}');
  print('validPerson: ${validate(validPerson)}');
}
  

5. create a file in tool folder called build.dart and put next code on it:

import 'package:build_runner/build_runner.dart';
import 'package:dson/phase.dart';


main() async {
  await build(new PhaseGroup()
    ..addPhase(
      // In next line replace `example/**.dart` for the globs you want to use as input, for example `**/*.dart`
      // to take all the dart files of the project as input.
        dsonPhase(const ['example/**.dart'])),
      deleteFilesByDefault: true);
}

6. run tool/build.dart. Then you will see that the file bin/drails_validator_sample.g.dart has been generated and it will contains the next code:

// GENERATED CODE - DO NOT MODIFY BY HAND

part of Validator.example;

// **************************************************************************
// Generator: InitMirrorsGenerator
// Target: library Validator.example
// **************************************************************************

_initMirrors() {
  initClassMirrors({Person: PersonClassMirror});
  initFunctionMirrors({});
}

// **************************************************************************
// Generator: DsonGenerator
// Target: class Person
// **************************************************************************

abstract class _$PersonSerializable extends SerializableMap {
  int get id;
  String get firstName;
  String get lastName;
  String get email;
  DateTime get dateOfBirth;
  String get ssn;
  void set id(int v);
  void set firstName(String v);
  void set lastName(String v);
  void set email(String v);
  void set dateOfBirth(DateTime v);
  void set ssn(String v);

  operator [](Object key) {
    switch (key) {
      case 'id':
        return id;
      case 'firstName':
        return firstName;
      case 'lastName':
        return lastName;
      case 'email':
        return email;
      case 'dateOfBirth':
        return dateOfBirth;
      case 'ssn':
        return ssn;
    }
    throwFieldNotFoundException(key, 'Person');
  }

  operator []=(Object key, value) {
    switch (key) {
      case 'id':
        id = value;
        return;
      case 'firstName':
        firstName = value;
        return;
      case 'lastName':
        lastName = value;
        return;
      case 'email':
        email = value;
        return;
      case 'dateOfBirth':
        dateOfBirth = value;
        return;
      case 'ssn':
        ssn = value;
        return;
    }
    throwFieldNotFoundException(key, 'Person');
  }

  get keys => PersonClassMirror.fields.keys;
}

_Person__Constructor(params) => new Person();

const $$Person_fields_id = const DeclarationMirror(type: int);
const $$Person_fields_firstName = const DeclarationMirror(
    type: String,
    annotations: const [
      const Length(min: 2, max: null, customDescription: null)
    ]);
const $$Person_fields_lastName = const DeclarationMirror(
    type: String,
    annotations: const [
      const Length(min: 2, max: null, customDescription: null)
    ]);
const $$Person_fields_email = const DeclarationMirror(
    type: String,
    annotations: const [
      const ValidIf(isEmail, customDescription: r'The entered email is invalid')
    ]);
const $$Person_fields_dateOfBirth =
    const DeclarationMirror(type: DateTime, annotations: const [
  const ValidIf(lowerThanOrEqualNow,
      customDescription: r'Values after now are not allowed')
]);
const $$Person_fields_ssn = const DeclarationMirror(
    type: String,
    annotations: const [
      const ValidIf(isSSN, customDescription: r'The entered SSN is invalid')
    ]);

const PersonClassMirror =
    const ClassMirror(name: 'Person', constructors: const {
  '': const FunctionMirror(parameters: const {}, call: _Person__Constructor)
}, fields: const {
  'id': $$Person_fields_id,
  'firstName': $$Person_fields_firstName,
  'lastName': $$Person_fields_lastName,
  'email': $$Person_fields_email,
  'dateOfBirth': $$Person_fields_dateOfBirth,
  'ssn': $$Person_fields_ssn
}, getters: const [
  'id',
  'firstName',
  'lastName',
  'email',
  'dateOfBirth',
  'ssn'
], setters: const [
  'id',
  'firstName',
  'lastName',
  'email',
  'dateOfBirth',
  'ssn'
]);

7. Finally you can run the file bin/drails_validator_sample.dart. If everything is ok you will see next output in console:

invalidPerson: isValid: false, errors: {firstName: [Length should be greather than 2], lastName: [Length should be greather than 2], email: [The entered email is invalid], dateOfBirth: [Values after now are not allowed], ssn: [The entered SSN is invalid]}
validPerson: isValid: true, errors: {}