Zard 🧩 #

Zard is a schema validation and transformation library for Dart, inspired by the popular Zod library for JavaScript. With Zard, you can define schemas to validate and transform data easily and intuitively.

Support 💖 #

If you find Darto useful, please consider supporting its development 🌟Buy Me a Coffee.🌟 Your support helps us improve the framework and make it even better!

Installation 📦 #

Add the following line to your pubspec.yaml:

dependencies:
  zard: ^0.0.1

Then, run:

flutter pub get

Or run:

dart pub add zard

Usage 🚀 #

Defining Schemas #

Zard allows you to define schemas for various data types. Here are some examples of how to use Zard:

String

import 'package:zard/zard.dart';

void main() {
  // String validations
  final schema = z.string().min(3).max(10).email(message: "Invalid email address").optional();

  final result = schema.parse("[email protected]");
  print(result); // [email protected]

  final nullResult = schema.parse(null);
  print(nullResult); // null
}

Int

import 'package:zard/zard.dart';

void main() {
  // Integer validations
  final schema = z.int().min(1).max(100).optional();

  final result = schema.parse(50);
  print(result); // 50

  final nullResult = schema.parse(null);
  print(nullResult); // null
}

Double

import 'package:zard/zard.dart';

void main() {
  // Double validations
  final schema = z.doubleType().min(1.0).max(100.0).optional();

  final result = schema.parse(50.5);
  print(result); // 50.5

  final nullResult = schema.parse(null);
  print(nullResult); // null
}

Boolean

import 'package:zard/zard.dart';

void main() {
  // Boolean validations
  final schema = z.boolean().optional();

  final result = schema.parse(true);
  print(result); // true

  final nullResult = schema.parse(null);
  print(nullResult); // null
}

import 'package:zard/zard.dart';

void main() {
  // List validations
  final schema = z.list(z.string().min(3)).optional();

  final result = schema.parse(["abc", "def"]);
  print(result); // [abc, def]

  final nullResult = schema.parse(null);
  print(nullResult); // null
}

Map

import 'package:zard/zard.dart';

void main() {
  // Map validations
  final schema = z.map({
    'name': z.string().min(3).optional(),
    'age': z.int().min(1).optional(),
  });

  final result = schema.parse({
    'name': 'John Doe',
    'age': 30,
  });
  print(result); // {name: John Doe, age: 30}

  final nullResult = schema.parse({
    'name': null,
    'age': null,
  });
  print(nullResult); // {name: null, age: null}
}

Error Handling with ZardError #

Zard provides comprehensive error handling through the ZardError class. When a validation fails, Zard returns a ZardError object that contains detailed information about the error.

ZardError Fields

• message: A descriptive message about the error.
• type: The type of error (e.g., min_error, max_error, type_error).
• value: The value that caused the error.

Example of Handling Errors

import 'package:zard/zard.dart';

void main() {
  // Integer validations
  final schema = z.int().min(10, message: 'Value must be at least 10');

  final result = schema.safeParse(5);

  if (!result['success']) {
    for (var error in result['errors']) {
      print('Error: ${error.message}, Type: ${error.type}, Value: ${error.value}');
    }
  }

  // or
  print
  print(schema.getErrors());
  // [ZardError(message: Value must be at least 10, type: min_error, value: 5)]
}

In this example, if the value 5 does not meet the minimum requirement of 10, Zard will return a ZardError object containing the error details.

Available Methods #

Here is a list of all the currently available methods in Zard:

ZString

• min(int length, {String? message})
• max(int length, {String? message})
• email({String? message})
• url({String? message})
• length(int length, {String? message})
• uuid({String? message})
• cuid({String? message})
• cuid2({String? message})
• regex(RegExp regex, {String? message})
• endsWith(String suffix, {String? message})
• startsWith(String prefix, {String? message})
• contains(String substring, {String? message})
• datetime({String? message})
• date({String? message})
• time({String? message})
• trim()
• toLowerCase()
• toUpperCase()
• capitalize()
• optional()

ZInt

• min(int length, {String? message})
• max(int length, {String? message})
• positive({String? message})
• nonnegative({String? message})
• negative({String? message})
• multipleOf(int divisor, {String? message})
• step(int stepValue, {String? message})
• optional()

ZDouble

• min(double length, {String? message})
• max(double length, {String? message})
• positive({String? message})
• nonnegative({String? message})
• negative({String? message})
• multipleOf(double divisor, {String? message})
• step(double stepValue, {String? message})
• optional()

ZBoolean

• boolean({String? message})
• optional()

ZList

• list(Schema itemSchema)
• optional()

ZMap

• map(Map<String, Schema> schemas)
• optional()

ZEnum

• ZEnum(List<String> list, {String? message})
• extract(List<String> list)
• exclude(List<String> list)
• optional()

Similarity to Zod #

Zard was inspired by Zod, a schema validation library for JavaScript. Just like Zod, Zard provides an easy-to-use API for defining validation and transformation schemas. The main difference is that Zard is specifically designed for Dart and Flutter, leveraging the features and syntax of the Dart language.

Contribution #

Contributions are welcome! Feel free to open issues and pull requests on the GitHub repository.

License #

This project is licensed under the MIT License. See the LICENSE file for more details.

Made with ❤️ for Dart/Flutter developers! 🎯