validator

README

Ctrix Validator

A lightweight and chainable Go validation library designed for fast development, focusing on a "first error per field" approach. This library is inspired Chaining Validation from other languages.

Features

• Fluent Chaining API: Apply multiple validation rules to a field in a concise, readable chain.
• "First Error Per Field": Validation for a given field stops after the first error is detected for that field.
• Default Required: All fields are considered required by default.
• Optional Fields: Easily mark fields as optional using .NotRequired().
• Graceful nullish Handling: Optional fields with nullish data are skipped entirely, incurring no errors.
• Concise Error Reporting: Collects and returns a slice of validationError structs.
• Silent Type Mismatch Skipping: Designed for rapid development, type mismatches during validation (e.g., calling Email() on an int) will result in the specific validation rule being silently skipped without adding an error.

Installation

To use this library, you can fetch it using go get:

go get github.com/mcctrix/ctrix-validator

Usage

Basic Usage

package main

import (
	validator "github.com/mcctrix/ctrix-validator"
)

func main() {
	vApp := validator.NewValidator("email", "test@test.com").Email().Min(5).Max(30).HasSpecialChar()
	vApp.NextField("url", "https://google.com").Url()
	vApp.NextField("number", 10).Min(5).Max(15)
	vApp.NextField("float", 10.5).Min(5).Max(15)
	vApp.NextField("username", "ctrix").Min(4).Max(10).HasSpecialChar()

	if err := vApp.GetError(); err != nil {
		for _, err := range vApp.GetError() {
			println(err.Field, err.Message)
		}
	}
}

Output: username must contain at least one special character

Practical Usage

package main

import (
	validator "github.com/mcctrix/ctrix-validator"
)

type userData struct {
	Email    string `json:"email"`
	Username string `json:"username"`
	Password string `json:"password"`
	QuestNum int    `json:"questNum"`
}


func main() {
	app.Post("/user", func(c fiber.Ctx) error {
		data := &userData{}
		if err := json.Unmarshal(c.BodyRaw(), data); err != nil {
			fmt.Println(err)
			return fiber.ErrInternalServerError
		}

		vApp := validator.NewValidator("email", data.Email).Email()
		vApp.NextField("username", data.Username).Min(5).Max(25)
		vApp.NextField("password", data.Password).Min(8)
		vApp.NextField("Quest Number", data.QuestNum).NotRequired().Min(10).Max(20)

		if err := vApp.GetError(); err != nil {
			for _, errr := range err {
				fmt.Println("Error from Ctrix Validator: ", errr)
				return c.JSON(errr)
			}
		}

		return c.SendString("Data is Successfully added!")
	})
}

Payload:

{
   "username": "ctrix",
   "email": "ctrix@gmail.com",
   "password": "123456798",
   "questNum": 25
}

Error:

{
  "Field": "username",
  "Message": "must be greater than or equal to 5"
}

Note: In this example we are sending the first error that occurs in the chain. however getError() has details of all the errors that happened accross all the fields

Documentation

Index

• func NewValidator(fieldName string, data interface{}) *validatorApp

Functions

func NewValidator

func NewValidator(fieldName string, data interface{}) *validatorApp

- fieldName: name of the field

- data: data to be validated

- returns: validatorApp

- Note: By Default field is considered required, please use NotRequired() immeadiately after to make it optional