validation

go-lua-validation

A GopherLua module for data validation in Lua scripts.

Installation

go get github.com/kerimovok/go-lua-validation

Usage

In Go

import (
    lua "github.com/yuin/gopher-lua"
    validation "github.com/kerimovok/go-lua-validation"
)

L := lua.NewState()
defer L.Close()

// Preload the validation module
L.PreloadModule("validation", validation.Loader)

// Now Lua scripts can use require("validation")
L.DoString(`
    local validation = require("validation")
    if validation.validate_email("user@example.com") then
        print("Valid email")
    end
`)

In Lua

local validation = require("validation")

-- Type checking
if validation.is_string(value) then
    print("It's a string")
end

if validation.is_number(value) then
    print("It's a number")
end

if validation.is_table(value) then
    print("It's a table")
end

-- Empty check
if validation.is_empty(value) then
    error("Value cannot be empty")
end

-- Email validation
if not validation.validate_email(email) then
    error("Invalid email address")
end

-- URL validation
if not validation.validate_url(url) then
    error("Invalid URL")
end

-- Regex validation
local isValid, err = validation.validate_regex("abc123", "^[a-z]+[0-9]+$")
if err then
    error("Invalid regex pattern: " .. err)
elseif not isValid then
    error("String does not match pattern")
end

-- Length validation
if not validation.min_length(password, 8) then
    error("Password must be at least 8 characters")
end

if not validation.max_length(username, 50) then
    error("Username must be at most 50 characters")
end

-- Range validation
if not validation.in_range(age, 18, 120) then
    error("Age must be between 18 and 120")
end

Functions

Type Checking

validation.is_string(value)

Checks if a value is a string.

• Parameters:
  • value: Value to check
• Returns:
  • boolean: true if string, false otherwise

validation.is_number(value)

Checks if a value is a number.

• Parameters:
  • value: Value to check
• Returns:
  • boolean: true if number, false otherwise

validation.is_table(value)

Checks if a value is a table.

• Parameters:
  • value: Value to check
• Returns:
  • boolean: true if table, false otherwise

validation.is_boolean(value)

Checks if a value is a boolean.

• Parameters:
  • value: Value to check
• Returns:
  • boolean: true if boolean, false otherwise

validation.is_nil(value)

Checks if a value is nil.

• Parameters:
  • value: Value to check
• Returns:
  • boolean: true if nil, false otherwise

Value Validation

validation.is_empty(value)

Checks if a value is empty (nil, empty string, or empty table).

• Parameters:
  • value: Value to check
• Returns:
  • boolean: true if empty, false otherwise

Format Validation

validation.validate_email(email)

Validates an email address.

• Parameters:
  • email (string): Email address to validate
• Returns:
  • boolean: true if valid email, false otherwise

validation.validate_url(url)

Validates a URL.

• Parameters:
  • url (string): URL to validate
• Returns:
  • boolean: true if valid URL, false otherwise

validation.validate_regex(str, pattern)

Validates a string against a regex pattern.

• Parameters:
  • str (string): String to validate
  • pattern (string): Regex pattern
• Returns:
  • boolean: true if matches, false otherwise (or nil if regex pattern is invalid)
  • string (error): Error message if regex pattern is invalid (only returned on error)

Length Validation

validation.min_length(str, min)

Checks if a string has minimum length.

• Parameters:
  • str (string): String to check
  • min (number): Minimum length
• Returns:
  • boolean: true if length >= min, false otherwise

validation.max_length(str, max)

Checks if a string has maximum length.

• Parameters:
  • str (string): String to check
  • max (number): Maximum length
• Returns:
  • boolean: true if length <= max, false otherwise

Range Validation

validation.in_range(num, min, max)

Checks if a number is within a range.

• Parameters:
  • num (number): Number to check
  • min (number): Minimum value
  • max (number): Maximum value
• Returns:
  • boolean: true if min <= num <= max, false otherwise

Notes

• Email validation uses Go's net/mail package
• URL validation uses Go's net/url package
• Regex patterns use Go's regex syntax (RE2)
• All validation functions are safe and do not throw errors (except validate_regex which may return an error for invalid patterns)