@shanewas/form-validation
v1.3.3
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A powerful and flexible validation engine for forms with support for complex rules, dependencies, and custom validations.
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@shanewas/form-validation
A powerful and flexible validation engine for forms with support for complex rules, dependencies, type validation, and custom validation logic.
Features
- Comprehensive Validation Types: Supports required fields, comparisons, dependencies, type checking, regex, and more.
- Flexible Actions: Execute form actions like CLEAR_FORMFIELD, UPDATE_VALUE, or custom actions based on validations.
- Complex Field Dependencies: Define validations based on the values of other fields.
- Custom Validations: Implement application-specific validation logic.
- Detailed Error Reporting: Easy-to-understand validation results.
- Flexible Rule Structure: Configure validations using a simple and extensible rule schema.
- Works Everywhere: Compatible with both Node.js and browsers.
Installation
Install via npm:
npm install @shanewas/form-validation
Quick Start
import { ValidationController } from "@shanewas/form-validation";
// Initialize the validator
const validator = new ValidationController();
// Define form data
const formData = {
name: { fieldId: "name", value: "john" },
age: { fieldId: "age", value: 18 },
email: { fieldId: "email", value: "[email protected]" },
};
// Define validation rules
const rules = [
{
ruleId: "userValidation",
conditions: [
{
fieldId: "name",
type: "REQUIRED",
errorMessage: "Name is required",
},
{
fieldId: "age",
type: "COMPARISON",
operator: "GREATER_THAN",
value: 17,
errorMessage: "Must be 18 or older",
},
],
},
];
// Validate
(async () => {
try {
const result = await validator.validateForm(formData, rules);
console.log(result);
} catch (error) {
console.error("Validation failed:", error);
}
})();
Validation Types
REQUIRED
: Ensure the field is not empty.COMPARISON
: Compare field values using supported operators.DEPENDENCY
: Validate a field based on another field's value.TYPE_CHECK
: Check the field value's data type.LENGTH_CHECK
: Validate the length of string or array fields.EMPTY_CHECK
: Ensure fields are empty or non-empty.REGEX
: Match field values against regular expressions.CUSTOM
: Apply user-defined validation functions.
Rule Structure
Rules are defined as objects and support a wide range of properties:
{ ruleId: string, conditions: [ { fieldId: string, type: string, operator: string, value: any, expectedType: string, minLength: number, maxLength: number, dependentFieldId: string, dependentOperator: string, dependentValue: any, action: string, // e.g., "CLEAR_FORMFIELD", "UPDATE_VALUE" actionValue: any, // Additional data for the action errorMessage: string, description: string, }, ], }
Actions
The following actions are supported for rule conditions:
CLEAR_FORMFIELD
: Clears the value of the specified field.UPDATE_VALUE
: Updates the field's value to a specified value.- Custom Actions: Define custom actions in your implementation.
Operators
The following operators are supported in COMPARISON
and DEPENDENCY
validations:
EQUALS
NOT_EQUALS
GREATER_THAN
LESS_THAN
GREATER_THAN_OR_EQUAL
LESS_THAN_OR_EQUAL
CONTAINS
STARTS_WITH
ENDS_WITH
BETWEEN
EMPTY
NOT_EMPTY
Advanced Usage
Custom Validation
You can define your own validation logic using the CUSTOM
type:
const rules = [
{
ruleId: "passwordValidation",
conditions: [
{
fieldId: "password",
type: "CUSTOM",
customFunction: async (value, formData) => {
return value.length < 8
? "Password must be at least 8 characters"
: null;
},
},
],
},
];
Dependent Fields
Validate a field based on the value of another field using DEPENDENCY
:
const rules = [
{
ruleId: "dependencyCheck",
conditions: [
{
fieldId: "state",
type: "DEPENDENCY",
dependentFieldId: "country",
dependentOperator: "EQUALS",
dependentValue: "USA",
errorMessage: "State is required for USA",
},
],
},
];
Validation Result
The validation result provides detailed information about errors:
{
hasErrors: true,
errorCount: 2,
details: {
name: [{ message: "Name is required", type: "REQUIRED" }],
age: [{ message: "Must be 18 or older", type: "COMPARISON" }],
},
summary: [
{ type: "error", fieldId: "name", message: "Name is required" },
{ type: "error", fieldId: "age", message: "Must be 18 or older" },
],
}
Example Validation with All Types
const formData = {
username: { fieldId: "username", value: "" },
age: { fieldId: "age", value: 17 },
email: { fieldId: "email", value: "invalid-email" },
};
const rules = [
{
fieldId: "username",
type: "REQUIRED",
errorMessage: "Username is required",
},
{
fieldId: "age",
type: "COMPARISON",
operator: "GREATER_THAN",
value: 18,
errorMessage: "Must be 18 or older",
},
{
fieldId: "email",
type: "REGEX",
value: /^[^\s@]+@[^\s@]+\.[^\s@]+$/,
errorMessage: "Invalid email format",
},
];
(async () => {
try {
const result = await validator.validateForm(formData, rules);
console.log(result);
} catch (error) {
console.error("Validation failed:", error);
}
})();
Requirements
- Node.js: Version 16 or later.
- Browser Support: ES Modules and modern browsers.
Contributing
We welcome contributions! Please see our Contributing Guidelines.
License
This project is licensed under the GNU General Public License v3.0. See the LICENSE file for details.
Support
Acknowledgments
Special thanks to all contributors for their efforts in making this library robust and versatile!