valid

Simple input validation for Go. This package does not deal with any form of input processing.

This package is all about checking if values satisfy different validation rules. It is outside the goals of this package to deal with web form input processing. There are already plenty of librbaries doing that.

Usage

```go
// A variable to validate.
var input string

// ... input processing (e.g. from web forms) ...

// Validation
errs := valid.String(input, Nonempty("This field is required."), MaxLen(20, "Input is too long."))

// errs is an []error containing errors with the relevant error messages.
```

Current validators

Strings

• Len - Length in closed interval [min, max].
• LenStrict - Length in open interval (min, max).
• MinLen - Length at least min.
• MinLenStrict - Length at least min+1.
• MaxLen - Length at most max.
• MaxLenStrict - Length at most max-1.
• Nonempty - string must not be empty.
• EmailRFC - e-mail address validation using the net/mail package.
• Email - e-mail address validation using the HTML5 Email field regexp.
• Regex - Validate using regular expression, given as string.
• RegexCompiled - Validate using regular expression, given as *regexp.Regexp.

Create custom validators

Validators are different for each type, but they all have similar interfaces.

Strings

The interface StringValidator has one method Validate(string) error. Any struct that implements this interface can be used as a string validator.

A convenience type is also defined: type StringFunc func(val string) error. This type implements the StringValidator interface, so any function with the above signature can be used as a validator.

Example

You can see code for a custom validator here https://gist.github.com/vladvelici/00679f8dff9e205cc157.