validation

package
v0.0.0-...-2915996 Latest Latest
Warning

This package is not in the latest version of its module.

 Go to latest Published: Sep 28, 2025 License: Apache-2.0 Imports: 17 Imported by: 0

README

validation

GoDoc Build Status Coverage Status Go Report

Description

ozzo-validation is a Go package that provides configurable and extensible data validation capabilities. It has the following features:

  • use normal programming constructs rather than error-prone struct tags to specify how data should be validated.
  • can validate data of different types, e.g., structs, strings, byte slices, slices, maps, arrays.
  • can validate custom data types as long as they implement the Validatable interface.
  • can validate data types that implement the sql.Valuer interface (e.g. sql.NullString).
  • customizable and well-formatted validation errors.
  • error code and message translation support.
  • provide a rich set of validation rules right out of box.
  • extremely easy to create and use custom validation rules.

For an example on how this library is used in an application, please refer to go-rest-api which is a starter kit for building RESTful APIs in Go.

Requirements

Go 1.13 or above.

Getting Started

The ozzo-validation package mainly includes a set of validation rules and two validation methods. You use validation rules to describe how a value should be considered valid, and you call either validation.Validate() or validation.ValidateStruct() to validate the value.

Validating a Simple Value

For a simple value, such as a string or an integer, you may use validation.Validate() to validate it. For example,

package main

import (
  "context"
  "fmt"
)

func main() {
  data := "example"
  ctx := context.Background()
  err := validation.Validate(ctx, data,
    validation.Required,       // not empty
    validation.Length(5, 100), // length between 5 and 100
    is.URL,                    // is a valid URL
  )
  fmt.Println(err)
  // Output:
  // must be a valid URL
}

The method validation.Validate() will run through the rules in the order that they are listed. If a rule fails the validation, the method will return the corresponding error and skip the rest of the rules. The method will return nil if the value passes all validation rules.

Validating a Struct

For a struct value, you usually want to check if its fields are valid. For example, in a RESTful application, you may unmarshal the request payload into a struct and then validate the struct fields. If one or multiple fields are invalid, you may want to get an error describing which fields are invalid. You can use validation.ValidateStruct() to achieve this purpose. A single struct can have rules for multiple fields, and a field can be associated with multiple rules. For example,

type Address struct {
	Street string
	City   string
	State  string
	Zip    string
}

func (a Address) Validate(ctx context.Context) error {
	return validation.ValidateStruct(ctx, &a,
		// Street cannot be empty, and the length must between 5 and 50
		validation.Field(&a.Street, validation.Required, validation.Length(5, 50)),
		// City cannot be empty, and the length must between 5 and 50
		validation.Field(&a.City, validation.Required, validation.Length(5, 50)),
		// State cannot be empty, and must be a string consisting of two letters in upper case
		validation.Field(&a.State, validation.Required, validation.Match(regexp.MustCompile("^[A-Z]{2}$"))),
		// State cannot be empty, and must be a string consisting of five digits
		validation.Field(&a.Zip, validation.Required, validation.Match(regexp.MustCompile("^[0-9]{5}$"))),
	)
}

a := Address{
    Street: "123",
    City:   "Unknown",
    State:  "Virginia",
    Zip:    "12345",
}

err := a.Validate(ctx)
fmt.Println(err)
// Output:
// Street: the length must be between 5 and 50; State: must be in a valid format.

Note that when calling validation.ValidateStruct to validate a struct, you should pass to the method a pointer to the struct instead of the struct itself. Similarly, when calling validation.Field to specify the rules for a struct field, you should use a pointer to the struct field.

When the struct validation is performed, the fields are validated in the order they are specified in ValidateStruct. And when each field is validated, its rules are also evaluated in the order they are associated with the field. If a rule fails, an error is recorded for that field, and the validation will continue with the next field.

Validating a Map

Sometimes you might need to work with dynamic data stored in maps rather than a typed model. You can use validation.Map() in this situation. A single map can have rules for multiple keys, and a key can be associated with multiple rules. For example,

c := map[string]interface{}{
	"Name":  "Qiang Xue",
	"Email": "q",
	"Address": map[string]interface{}{
		"Street": "123",
		"City":   "Unknown",
		"State":  "Virginia",
		"Zip":    "12345",
	},
}

err := validation.Validate(ctx, c,
	validation.Map(
		// Name cannot be empty, and the length must be between 5 and 20.
		validation.Key("Name", validation.Required, validation.Length(5, 20)),
		// Email cannot be empty and should be in a valid email format.
		validation.Key("Email", validation.Required, is.Email),
		// Validate Address using its own validation rules
		validation.Key("Address", validation.Map(
			// Street cannot be empty, and the length must between 5 and 50
			validation.Key("Street", validation.Required, validation.Length(5, 50)),
			// City cannot be empty, and the length must between 5 and 50
			validation.Key("City", validation.Required, validation.Length(5, 50)),
			// State cannot be empty, and must be a string consisting of two letters in upper case
			validation.Key("State", validation.Required, validation.Match(regexp.MustCompile("^[A-Z]{2}$"))),
			// State cannot be empty, and must be a string consisting of five digits
			validation.Key("Zip", validation.Required, validation.Match(regexp.MustCompile("^[0-9]{5}$"))),
		)),
	),
)
fmt.Println(err)
// Output:
// Address: (State: must be in a valid format; Street: the length must be between 5 and 50.); Email: must be a valid email address.

When the map validation is performed, the keys are validated in the order they are specified in Map. And when each key is validated, its rules are also evaluated in the order they are associated with the key. If a rule fails, an error is recorded for that key, and the validation will continue with the next key.

Validation Errors

The validation.ValidateStruct method returns validation errors found in struct fields in terms of validation.Errors which is a map of fields and their corresponding errors. Nil is returned if validation passes.

By default, validation.Errors uses the struct tags named json to determine what names should be used to represent the invalid fields. The type also implements the json.Marshaler interface so that it can be marshaled into a proper JSON object. For example,

type Address struct {
	Street string `json:"street"`
	City   string `json:"city"`
	State  string `json:"state"`
	Zip    string `json:"zip"`
}

// ...perform validation here...

err := a.Validate(ctx)
b, _ := json.Marshal(err)
fmt.Println(string(b))
// Output:
// {"street":"the length must be between 5 and 50","state":"must be in a valid format"}

You may modify validation.ErrorTag to use a different struct tag name.

If you do not like the magic that ValidateStruct determines error keys based on struct field names or corresponding tag values, you may use the following alternative approach:

c := Customer{
	Name:  "Qiang Xue",
	Email: "q",
	Address: Address{
		State:  "Virginia",
	},
}

err := validation.Errors{
	"name": validation.Validate(ctx, c.Name, validation.Required, validation.Length(5, 20)),
	"email": validation.Validate(ctx, c.Name, validation.Required, is.Email),
	"zip": validation.Validate(ctx, c.Address.Zip, validation.Required, validation.Match(regexp.MustCompile("^[0-9]{5}$"))),
}.Filter()
fmt.Println(err)
// Output:
// email: must be a valid email address; zip: cannot be blank.

In the above example, we build a validation.Errors by a list of names and the corresponding validation results. At the end we call Errors.Filter() to remove from Errors all nils which correspond to those successful validation results. The method will return nil if Errors is empty.

The above approach is very flexible as it allows you to freely build up your validation error structure. You can use it to validate both struct and non-struct values. Compared to using ValidateStruct to validate a struct, it has the drawback that you have to redundantly specify the error keys while ValidateStruct can automatically find them out.

Internal Errors

Internal errors are different from validation errors in that internal errors are caused by malfunctioning code (e.g. a validator making a remote call to validate some data when the remote service is down) rather than the data being validated. When an internal error happens during data validation, you may allow the user to resubmit the same data to perform validation again, hoping the program resumes functioning. On the other hand, if data validation fails due to data error, the user should generally not resubmit the same data again.

To differentiate internal errors from validation errors, when an internal error occurs in a validator, wrap it into validation.InternalError by calling validation.NewInternalError(). The user of the validator can then check if a returned error is an internal error or not. For example,

if err := a.Validate(ctx); err != nil {
	if e, ok := err.(validation.InternalError); ok {
		// an internal error happened
		fmt.Println(e.InternalError())
	}
}

Validatable Types

A type is validatable if it implements the validation.Validatable interface.

When validation.Validate is used to validate a validatable value, if it does not find any error with the given validation rules, it will further call the value's Validate() method.

Similarly, when validation.ValidateStruct is validating a struct field whose type is validatable, it will call the field's Validate method after it passes the listed rules.

Note: When implementing validation.Validatable, do not call validation.Validate() to validate the value in its original type because this will cause infinite loops. For example, if you define a new type MyString as string and implement validation.Validatable for MyString, within the Validate() function you should cast the value to string first before calling validation.Validate() to validate it.

In the following example, the Address field of Customer is validatable because Address implements validation.Validatable. Therefore, when validating a Customer struct with validation.ValidateStruct, validation will "dive" into the Address field.

type Customer struct {
	Name    string
	Gender  string
	Email   string
	Address Address
}

func (c Customer) Validate(ctx context.Context) error {
	return validation.ValidateStruct(ctx, &c,
		// Name cannot be empty, and the length must be between 5 and 20.
		validation.Field(&c.Name, validation.Required, validation.Length(5, 20)),
		// Gender is optional, and should be either "Female" or "Male".
		validation.Field(&c.Gender, validation.In("Female", "Male")),
		// Email cannot be empty and should be in a valid email format.
		validation.Field(&c.Email, validation.Required, is.Email),
		// Validate Address using its own validation rules
		validation.Field(&c.Address),
	)
}

c := Customer{
	Name:  "Qiang Xue",
	Email: "q",
	Address: Address{
		Street: "123 Main Street",
		City:   "Unknown",
		State:  "Virginia",
		Zip:    "12345",
	},
}

err := c.Validate(ctx)
fmt.Println(err)
// Output:
// Address: (State: must be in a valid format.); Email: must be a valid email address.

Sometimes, you may want to skip the invocation of a type's Validate method. To do so, simply associate a validation.Skip rule with the value being validated.

Maps/Slices/Arrays of Validatables

When validating an iterable (map, slice, or array), whose element type implements the validation.Validatable interface, the validation.Validate method will call the Validate method of every non-nil element. The validation errors of the elements will be returned as validation.Errors which maps the keys of the invalid elements to their corresponding validation errors. For example,

addresses := []Address{
	Address{State: "MD", Zip: "12345"},
	Address{Street: "123 Main St", City: "Vienna", State: "VA", Zip: "12345"},
	Address{City: "Unknown", State: "NC", Zip: "123"},
}
err := validation.Validate(ctx, addresses)
fmt.Println(err)
// Output:
// 0: (City: cannot be blank; Street: cannot be blank.); 2: (Street: cannot be blank; Zip: must be in a valid format.).

When using validation.ValidateStruct to validate a struct, the above validation procedure also applies to those struct fields which are map/slices/arrays of validatables.

Each

The Each validation rule allows you to apply a set of rules to each element of an array, slice, or map.

type Customer struct {
    Name      string
    Emails    []string
}

func (c Customer) Validate(ctx context.Context) error {
    return validation.ValidateStruct(ctx, &c,
        // Name cannot be empty, and the length must be between 5 and 20.
		validation.Field(&c.Name, validation.Required, validation.Length(5, 20)),
		// Emails are optional, but if given must be valid.
		validation.Field(&c.Emails, validation.Each(is.Email)),
    )
}

c := Customer{
    Name:   "Qiang Xue",
    Emails: []Email{
        "valid@example.com",
        "invalid",
    },
}

err := c.Validate(ctx)
fmt.Println(err)
// Output:
// Emails: (1: must be a valid email address.).
Pointers

When a value being validated is a pointer, most validation rules will validate the actual value pointed to by the pointer. If the pointer is nil, these rules will skip the validation.

An exception is the validation.Required and validation.NotNil rules. When a pointer is nil, they will report a validation error.

Types Implementing sql.Valuer

If a data type implements the sql.Valuer interface (e.g. sql.NullString), the built-in validation rules will handle it properly. In particular, when a rule is validating such data, it will call the Value() method and validate the returned value instead.

Required vs. Not Nil

When validating input values, there are two different scenarios about checking if input values are provided or not.

In the first scenario, an input value is considered missing if it is not entered or it is entered as a zero value (e.g. an empty string, a zero integer). You can use the validation.Required rule in this case.

In the second scenario, an input value is considered missing only if it is not entered. A pointer field is usually used in this case so that you can detect if a value is entered or not by checking if the pointer is nil or not. You can use the validation.NotNil rule to ensure a value is entered (even if it is a zero value).

Embedded Structs

The validation.ValidateStruct method will properly validate a struct that contains embedded structs. In particular, the fields of an embedded struct are treated as if they belong directly to the containing struct. For example,

type Employee struct {
	Name string
}

type Manager struct {
	Employee
	Level int
}

m := Manager{}
err := validation.ValidateStruct(&m,
	validation.Field(&m.Name, validation.Required),
	validation.Field(&m.Level, validation.Required),
)
fmt.Println(err)
// Output:
// Level: cannot be blank; Name: cannot be blank.

In the above code, we use &m.Name to specify the validation of the Name field of the embedded struct Employee. And the validation error uses Name as the key for the error associated with the Name field as if Name a field directly belonging to Manager.

If Employee implements the validation.Validatable interface, we can also use the following code to validate Manager, which generates the same validation result:

func (e Employee) Validate(ctx context.Context) error {
	return validation.ValidateStruct(ctx, &e,
		validation.Field(&e.Name, validation.Required),
	)
}

err := validation.ValidateStruct(&m,
	validation.Field(&m.Employee),
	validation.Field(&m.Level, validation.Required),
)
fmt.Println(err)
// Output:
// Level: cannot be blank; Name: cannot be blank.
Conditional Validation

Sometimes, we may want to validate a value only when certain condition is met. For example, we want to ensure the unit struct field is not empty only when the quantity field is not empty; or we may want to ensure either email or phone is provided. The so-called conditional validation can be achieved with the help of validation.When. The following code implements the aforementioned examples:

result := validation.ValidateStruct(&a,
    validation.Field(&a.Unit, validation.When(a.Quantity != "", validation.Required).Else(validation.Nil)),
    validation.Field(&a.Phone, validation.When(a.Email == "", validation.Required.Error('Either phone or Email is required.')),
    validation.Field(&a.Email, validation.When(a.Phone == "", validation.Required.Error('Either phone or Email is required.')),
)

Note that validation.When and validation.When.Else can take a list of validation rules. These rules will be executed only when the condition is true (When) or false (Else).

The above code can also be simplified using the shortcut validation.Required.When:

result := validation.ValidateStruct(&a,
    validation.Field(&a.Unit, validation.Required.When(a.Quantity != ""), validation.Nil.When(a.Quantity == "")),
    validation.Field(&a.Phone, validation.Required.When(a.Email == "").Error('Either phone or Email is required.')),
    validation.Field(&a.Email, validation.Required.When(a.Phone == "").Error('Either phone or Email is required.')),
)
Customizing Error Messages

All built-in validation rules allow you to customize their error messages. To do so, simply call the Error() method of the rules. For example,

data := "2123"
err := validation.Validate(ctx, data,
	validation.Required.Error("is required"),
	validation.Match(regexp.MustCompile("^[0-9]{5}$")).Error("must be a string with five digits"),
)
fmt.Println(err)
// Output:
// must be a string with five digits

You can also customize the pre-defined error(s) of a built-in rule such that the customization applies to every instance of the rule. For example, the Required rule uses the pre-defined error ErrRequired. You can customize it during the application initialization:

validation.ErrRequired = validation.ErrRequired.SetMessage("the value is required")
Error Code and Message Translation

The errors returned by the validation rules implement the Error interface which contains the Code() method to provide the error code information. While the message of a validation error is often customized, the code is immutable. You can use error code to programmatically check a validation error or look for the translation of the corresponding message.

If you are developing your own validation rules, you can use validation.NewError() to create a validation error which implements the aforementioned Error interface.

Creating Custom Rules

Creating a custom rule is as simple as implementing the validation.Rule interface. The interface contains a single method as shown below, which should validate the value and return the validation error, if any:

// Validate validates a value and returns an error if validation fails.
Validate(ctx context.Context, value interface{}) error

If you already have a function with the same signature as shown above, you can call validation.By() to turn it into a validation rule. For example,

func checkAbc(value interface{}) error {
	s, _ := value.(string)
	if s != "abc" {
		return errors.New("must be abc")
	}
	return nil
}

err := validation.Validate(ctx, "xyz", validation.By(checkAbc))
fmt.Println(err)
// Output: must be abc

If your validation function takes additional parameters, you can use the following closure trick:

func stringEquals(str string) validation.RuleFunc {
	return func(value interface{}) error {
		s, _ := value.(string)
        if s != str {
            return errors.New("unexpected string")
        }
        return nil
    }
}

err := validation.Validate(ctx, "xyz", validation.By(stringEquals("abc")))
fmt.Println(err)
// Output: unexpected string
Rule Groups

When a combination of several rules are used in multiple places, you may use the following trick to create a rule group so that your code is more maintainable.

var NameRule = []validation.Rule{
	validation.Required,
	validation.Length(5, 20),
}

type User struct {
	FirstName string
	LastName  string
}

func (u User) Validate(ctx context.Context) error {
	return validation.ValidateStruct(&u,
		validation.Field(&u.FirstName, NameRule...),
		validation.Field(&u.LastName, NameRule...),
	)
}

In the above example, we create a rule group NameRule which consists of two validation rules. We then use this rule group to validate both FirstName and LastName.

Context-aware Validation

While most validation rules are self-contained, some rules may depend dynamically on a context. A rule may implement the validation.RuleWithContext interface to support the so-called context-aware validation.

To validate an arbitrary value with a context, call validation.ValidateWithContext(). The context.Conext parameter will be passed along to those rules that implement validation.RuleWithContext.

To validate the fields of a struct with a context, call validation.ValidateStructWithContext().

You can define a context-aware rule from scratch by implementing both validation.Rule and validation.RuleWithContext. You can also use validation.WithContext() to turn a function into a context-aware rule. For example,

rule := validation.WithContext(func(ctx context.Context, value interface{}) error {
	if ctx.Value("secret") == value.(string) {
	    return nil
	}
	return errors.New("value incorrect")
})
value := "xyz"
ctx := context.WithValue(context.Background(), "secret", "example")
err := validation.ValidateWithContext(ctx, value, rule)
fmt.Println(err)
// Output: value incorrect

When performing context-aware validation, if a rule does not implement validation.RuleWithContext, its validation.Rule will be used instead.

Built-in Validation Rules

The following rules are provided in the validation package:

  • In(...interface{}): checks if a value can be found in the given list of values.
  • NotIn(...interface{}): checks if a value is NOT among the given list of values.
  • Length(min, max int): checks if the length of a value is within the specified range. This rule should only be used for validating strings, slices, maps, and arrays.
  • RuneLength(min, max int): checks if the length of a string is within the specified range. This rule is similar as Length except that when the value being validated is a string, it checks its rune length instead of byte length.
  • Min(min interface{}) and Max(max interface{}): checks if a value is within the specified range. These two rules should only be used for validating int, uint, float and time.Time types.
  • Match(*regexp.Regexp): checks if a value matches the specified regular expression. This rule should only be used for strings and byte slices.
  • Date(layout string): checks if a string value is a date whose format is specified by the layout. By calling Min() and/or Max(), you can check additionally if the date is within the specified range.
  • Required: checks if a value is not empty (neither nil nor zero).
  • NotNil: checks if a pointer value is not nil. Non-pointer values are considered valid.
  • NilOrNotEmpty: checks if a value is a nil pointer or a non-empty value. This differs from Required in that it treats a nil pointer as valid.
  • Nil: checks if a value is a nil pointer.
  • Empty: checks if a value is empty. nil pointers are considered valid.
  • Skip: this is a special rule used to indicate that all rules following it should be skipped (including the nested ones).
  • MultipleOf: checks if the value is a multiple of the specified range.
  • Each(rules ...Rule): checks the elements within an iterable (map/slice/array) with other rules.
  • When(condition, rules ...Rule): validates with the specified rules only when the condition is true.
  • Else(rules ...Rule): must be used with When(condition, rules ...Rule), validates with the specified rules only when the condition is false.

The is sub-package provides a list of commonly used string validation rules that can be used to check if the format of a value satisfies certain requirements. Note that these rules only handle strings and byte slices and if a string or byte slice is empty, it is considered valid. You may use a Required rule to ensure a value is not empty. Below is the whole list of the rules provided by the is package:

  • Email: validates if a string is an email or not. It also checks if the MX record exists for the email domain.
  • EmailFormat: validates if a string is an email or not. It does NOT check the existence of the MX record.
  • URL: validates if a string is a valid URL
  • RequestURL: validates if a string is a valid request URL
  • RequestURI: validates if a string is a valid request URI
  • Alpha: validates if a string contains English letters only (a-zA-Z)
  • Digit: validates if a string contains digits only (0-9)
  • Alphanumeric: validates if a string contains English letters and digits only (a-zA-Z0-9)
  • UTFLetter: validates if a string contains unicode letters only
  • UTFDigit: validates if a string contains unicode decimal digits only
  • UTFLetterNumeric: validates if a string contains unicode letters and numbers only
  • UTFNumeric: validates if a string contains unicode number characters (category N) only
  • LowerCase: validates if a string contains lower case unicode letters only
  • UpperCase: validates if a string contains upper case unicode letters only
  • Hexadecimal: validates if a string is a valid hexadecimal number
  • HexColor: validates if a string is a valid hexadecimal color code
  • RGBColor: validates if a string is a valid RGB color in the form of rgb(R, G, B)
  • Int: validates if a string is a valid integer number
  • Float: validates if a string is a floating point number
  • UUIDv3: validates if a string is a valid version 3 UUID
  • UUIDv4: validates if a string is a valid version 4 UUID
  • UUIDv5: validates if a string is a valid version 5 UUID
  • UUID: validates if a string is a valid UUID
  • CreditCard: validates if a string is a valid credit card number
  • ISBN10: validates if a string is an ISBN version 10
  • ISBN13: validates if a string is an ISBN version 13
  • ISBN: validates if a string is an ISBN (either version 10 or 13)
  • JSON: validates if a string is in valid JSON format
  • ASCII: validates if a string contains ASCII characters only
  • PrintableASCII: validates if a string contains printable ASCII characters only
  • Multibyte: validates if a string contains multibyte characters
  • FullWidth: validates if a string contains full-width characters
  • HalfWidth: validates if a string contains half-width characters
  • VariableWidth: validates if a string contains both full-width and half-width characters
  • Base64: validates if a string is encoded in Base64
  • DataURI: validates if a string is a valid base64-encoded data URI
  • E164: validates if a string is a valid E164 phone number (+19251232233)
  • CountryCode2: validates if a string is a valid ISO3166 Alpha 2 country code
  • CountryCode3: validates if a string is a valid ISO3166 Alpha 3 country code
  • DialString: validates if a string is a valid dial string that can be passed to Dial()
  • MAC: validates if a string is a MAC address
  • IP: validates if a string is a valid IP address (either version 4 or 6)
  • IPv4: validates if a string is a valid version 4 IP address
  • IPv6: validates if a string is a valid version 6 IP address
  • Subdomain: validates if a string is valid subdomain
  • Domain: validates if a string is valid domain
  • DNSName: validates if a string is valid DNS name
  • Host: validates if a string is a valid IP (both v4 and v6) or a valid DNS name
  • Port: validates if a string is a valid port number
  • MongoID: validates if a string is a valid Mongo ID
  • Latitude: validates if a string is a valid latitude
  • Longitude: validates if a string is a valid longitude
  • SSN: validates if a string is a social security number (SSN)
  • Semver: validates if a string is a valid semantic version

Credits

The is sub-package wraps the excellent validators provided by the govalidator package.

Documentation

Overview

Package validation provides configurable and extensible rules for validating data of various types.

Index

Constants

View Source 
const (
	RuleTypeRequired      = "required"
	RuleTypeNirOrNotEmpty = "nil_or_not_empty"
)
View Source 
const (
	MatchRuleType = "match"
)
View Source 
const (
	NotInRuleType = "not_in"
)
View Source 
const (
	RuleTypeDate = "date"
)
View Source 
const (
	RuleTypeDependsOn = "depends_on"
)
View Source 
const (
	RuleTypeMultipleOf = "multiple_of"
)
View Source 
const (
	RuleTypeNotNil = "not_nil"
)

Variables

View Source 
var (
	// ErrNil is the error that returns when a value is not nil.
	ErrNil = NewError("validation_nil", "must be blank")
	// ErrEmpty is the error that returns when a not nil value is not empty.
	ErrEmpty = NewError("validation_empty", "must be blank")
)
View Source 
var (
	// ErrDateInvalid is the error that returns in case of an invalid date.
	ErrDateInvalid = NewError("validation_date_invalid", "must be a valid date")
	// ErrDateOutOfRange is the error that returns in case of an invalid date.
	ErrDateOutOfRange = NewError("validation_date_out_of_range", "the date is out of range")
)
View Source 
var (
	// ErrJsonInvalid is the error that returns in case of an invalid json.
	ErrJsonInvalid = NewError("validation_json_invalid", "must be a valid json")
	// ErrJsonInvalidMarshall is the error that returns in case of an error during marshalling.
	ErrJsonInvalidMarshall = NewError("validation_json_invalid_marshall", "error marshalling json")
	// ErrJsonInvalidUnmarshall is the error that returns in case of an error during unmarshalling.
	ErrJsonInvalidUnmarshall = NewError("validation_json_invalid_unmarshall", "error unmarshalling json")
)
View Source 
var (
	// ErrLengthTooLong is the error that returns in case of too long length.
	ErrLengthTooLong = NewError("validation_length_too_long", "the length must be no more than {{.max}}")
	// ErrLengthTooShort is the error that returns in case of too short length.
	ErrLengthTooShort = NewError("validation_length_too_short", "the length must be no less than {{.min}}")
	// ErrLengthInvalid is the error that returns in case of an invalid length.
	ErrLengthInvalid = NewError("validation_length_invalid", "the length must be exactly {{.min}}")
	// ErrLengthOutOfRange is the error that returns in case of out of range length.
	ErrLengthOutOfRange = NewError("validation_length_out_of_range", "the length must be between {{.min}} and {{.max}}")
	// ErrLengthEmptyRequired is the error that returns in case of non-empty value.
	ErrLengthEmptyRequired = NewError("validation_length_empty_required", "the value must be empty")
)
View Source 
var (
	// ErrNotMap is the error that the value being validated is not a map.
	ErrNotMap = errors.New("only a map can be validated")

	// ErrKeyWrongType is the error returned in case of an incorrect key type.
	ErrKeyWrongType = NewError("validation_key_wrong_type", "key not the correct type")

	// ErrKeyMissing is the error returned in case of a missing key.
	ErrKeyMissing = NewError("validation_key_missing", "required key is missing")
)
View Source 
var (
	// ErrMinGreaterEqualThanRequired is the error that returns when a value is less than a specified threshold.
	ErrMinGreaterEqualThanRequired = NewError("validation_min_greater_equal_than_required", "must be no less than {{.threshold}}")
	// ErrMaxLessEqualThanRequired is the error that returns when a value is greater than a specified threshold.
	ErrMaxLessEqualThanRequired = NewError("validation_max_less_equal_than_required", "must be no greater than {{.threshold}}")
	// ErrMinGreaterThanRequired is the error that returns when a value is less than or equal to a specified threshold.
	ErrMinGreaterThanRequired = NewError("validation_min_greater_than_required", "must be greater than {{.threshold}}")
	// ErrMaxLessThanRequired is the error that returns when a value is greater than or equal to a specified threshold.
	ErrMaxLessThanRequired = NewError("validation_max_less_than_required", "must be less than {{.threshold}}")
)
View Source 
var (
	ErrValidationIntegerUnmarshal = NewError("validation_integer_unmarshal", "failed to unmarshal integer value")
	ErrValidationFloatUnmarshal   = NewError("validation_float_unmarshal", "failed to unmarshal float value")
	ErrValidationStringUnmarshal  = NewError("validation_string_unmarshal", "failed to unmarshal string value")
	ErrValidationBooleanUnmarshal = NewError("validation_boolean_unmarshal", "failed to unmarshal boolean value")
)
View Source 
var (
	// ErrRequired is the error that returns when a value is required.
	ErrRequired = NewError("validation_required", "cannot be blank")
	// ErrNilOrNotEmpty is the error that returns when a value is not nil and is empty.
	ErrNilOrNotEmpty = NewError("validation_nil_or_not_empty_required", "cannot be blank")
)
View Source 
var (
	// ErrorTag is the struct tag name used to customize the error field name for a struct field.
	ErrorTag = "json"

	// Skip is a special validation rule that indicates all rules following it should be skipped.
	Skip = skipRule{/* contains filtered or unexported fields */}
)
View Source 
var Empty = absentRule{
	// contains filtered or unexported fields
}

Empty checks if a not nil value is empty.

View Source 
var ErrCELCompilation = NewError("validation_cel_compilation_error", "CEL compilation error")

ErrCELCompilation is the error that returns when CEL compilation fails.

View Source 
var ErrCELEnvironment = NewError("validation_cel_error", "can't create CEL environment")

ErrCELEnvironment is the error that returns when CEL environment cannot be created.

View Source 
var ErrCELEvaluation = NewError("validation_cel_evaluation_error", "error evaluating CEL expression")

ErrCELEvaluation is the error that returns when CEL evaluation fails.

View Source 
var ErrCELProgram = NewError("validation_cel_program_error", "error creating CEL program")

ErrCELProgram is the error that returns when CEL program cannot be created.

View Source 
var ErrCriteriaIsNotMatch = NewError("validation_value_do_not_match_criteria", "value don't match criteria")

ErrCriteriaIsNotMatch is the error that returns in case of an invalid value for "in" rule.

View Source 
var ErrFalseInvalid = NewError("validation_false_invalid", "must be in a false value")

ErrFalseInvalid is the error that returns in case of changed value.

View Source 
var ErrInInvalid = NewError("validation_in_invalid", "must be a valid value")

ErrInInvalid is the error that returns in case of an invalid value for "in" rule.

View Source 
var ErrInvalidKey = NewError("validation_invalid_key", "key is not valid")

ErrInvalidKey is the error returned when a key in a map is not valid according to the specified rules.

View Source 
var ErrMatchInvalid = NewError("validation_match_invalid", "must be in a valid format")

ErrMatchInvalid is the error that returns in case of invalid format.

View Source 
var (
	// ErrMissingPrivilege is the error returned when a user does not have the required privilege.
	ErrMissingPrivilege = NewError("validation_missing_privilege", "user does not have the required privilege")
)
View Source 
var ErrMultipleOfInvalid = NewError("validation_multiple_of_invalid", "must be multiple of {{.base}}")

ErrMultipleOfInvalid is the error that returns when a value is not multiple of a base.

View Source 
var ErrNotInInvalid = NewError("validation_not_in_invalid", "must not be in list")

ErrNotInInvalid is the error that returns when a value is in a list.

View Source 
var ErrNotNilRequired = NewError("validation_not_nil_required", "is required")

ErrNotNilRequired is the error that returns when a value is Nil.

View Source 
var (
	// ErrStructPointer is the error that a struct being validated is not specified as a pointer.
	ErrStructPointer = errors.New("only a pointer to a struct can be validated")
)
View Source 
var ErrTrueInvalid = NewError("validation_true_invalid", "must be in a true value")

ErrTrueInvalid is the error that returns in case of changed value.

View Source 
var ErrTypeInvalid = NewError("validation_type_invalid", "must be a valid type")

ErrTypeInvalid is the error that returns in case of an invalid type for "type" rule.

View Source 
var ErrUnchangeableInvalid = NewError("validation_unchangeable_invalid", "must be in a unchangeable value")

ErrUnchangeableInvalid is the error that returns in case of changed value.

View Source 
var ErrUniqueDuplicate = NewError("validation_unique_duplication", "must be an unique value")

ErrUniqueDuplicate is the error that returns in case of an duplication value for "unique" rule.

View Source 
var ErrUniqueListDuplicate = NewError("validation_unique_list_duplication", "must have unique values")

ErrUniqueListDuplicate is the error that returns in case of an duplication value for "unique" rule.

View Source 
var Nil = absentRule{
	// contains filtered or unexported fields
}

Nil is a validation rule that checks if a value is nil. It is the opposite of NotNil rule

View Source 
var NilOrNotEmpty = RequiredRule{
	// contains filtered or unexported fields
}

NilOrNotEmpty checks if a value is a nil pointer or a value that is not empty. NilOrNotEmpty differs from Required in that it treats a nil pointer as valid.

View Source 
var NotNil = notNilRule{/* contains filtered or unexported fields */}

NotNil is a validation rule that checks if a value is not nil. NotNil only handles types including interface, pointer, slice, and map. All other types are considered valid.

View Source 
var PrimitiveErrors = map[string]Error{
	new(Integer).GetName(): ErrValidationIntegerUnmarshal,
	new(Float).GetName():   ErrValidationFloatUnmarshal,
	new(String).GetName():  ErrValidationStringUnmarshal,
	new(Boolean).GetName(): ErrValidationBooleanUnmarshal,
}
View Source 
var Required = RequiredRule{
	// contains filtered or unexported fields
}

Required is a validation rule that checks if a value is not empty. A value is considered not empty if - integer, float: not zero - bool: true - string, array, slice, map: len() > 0 - interface, pointer: not nil and the referenced value is not empty - any other types

Functions

func EnsureString 

func EnsureString(value interface{}) (string, error)

EnsureString ensures the given value is a string. If the value is a byte slice, it will be typecast into a string. An error is returned otherwise.

func GetThis 

func GetThis(ctx context.Context) any

func Indirect 

func Indirect(value interface{}) (interface{}, bool)

Indirect returns the value that the given interface or pointer references to. A boolean value is also returned to indicate if the value is nil or not (only applicable to interface, pointer, map, and slice). If the value is neither an interface nor a pointer, it will be returned back.

func IsChanged 

func IsChanged(original, value any) bool

IsChanged checks if the original value is changed compared to the new value.

func IsEmpty 

func IsEmpty(value interface{}) bool

IsEmpty checks if a value is empty or not. A value is considered empty if - integer, float: zero - bool: false - string, array: len() == 0 - slice, map: nil or len() == 0 - interface, pointer: nil or the referenced value is empty

func IsValidationError 

func IsValidationError(err error) bool

func IsVisited 

func IsVisited(ctx context.Context, ptr uintptr) bool

func LengthOfValue 

func LengthOfValue(value interface{}) (int, error)

LengthOfValue returns the length of a value that is a string, slice, map, or array. An error is returned for all other types.

func MarshalRule 

func MarshalRule(r RuleEx) ([]byte, error)

func MarshalRules 

func MarshalRules(rules []RuleEx) ([]byte, error)

func RegisterRule 

func RegisterRule(rule RuleEx)

func RegisterUnmarshaller 

func RegisterUnmarshaller(t RuleType, unmarshaller Unmarshaller)

func StringOrBytes 

func StringOrBytes(value interface{}) (isString bool, str string, isBytes bool, bs []byte)

StringOrBytes typecasts a value into a string or byte slice. Boolean flags are returned to indicate if the typecasting succeeds or not.

func ToFloat 

func ToFloat(value interface{}) (float64, error)

ToFloat converts the given value to a float64. An error is returned for all incompatible types.

func ToInt 

func ToInt(value interface{}) (int64, error)

ToInt converts the given value to an int64. An error is returned for all incompatible types.

func ToUint 

func ToUint(value interface{}) (uint64, error)

ToUint converts the given value to an uint64. An error is returned for all incompatible types.

func UpdateLevelChildrenNamesByModelTags 

func UpdateLevelChildrenNamesByModelTags(err error, model interface{}) error

UpdateLevelChildrenNamesByModelTags recurrence updates the names of the children in the error level by using the provided model's tags.

func Validate 

func Validate(ctx context.Context, value interface{}, rules ...Rule) error

Validate validates the given value with the given context and returns the validation error, if any.

Validate performs validation using the following steps:

  1. For each rule, call its `ValidateWithContext()` to validate the value if the rule implements `RuleWithContext`. Otherwise call `Validate()` of the rule. Return if any error is found.
  2. If the value being validated implements `ValidatableWithContext`, call the value's `ValidateWithContext()` and return with the validation result.
  3. If the value being validated implements `Validatable`, call the value's `Validate()` and return with the validation result.
  4. If the value being validated is a map/slice/array, and the element type implements `Validatable`, for each element call the element value's `Validate()`. Return with the validation result.

func ValidateStruct 

func ValidateStruct(ctx context.Context, structPtr interface{}, fields ...*FieldRules) error

ValidateStruct validates a struct by checking the specified struct fields against the corresponding validation rules. Note that the struct being validated must be specified as a pointer to it. If the pointer is nil, it is considered valid. Use Field() to specify struct fields that need to be validated. Each Field() call specifies a single field which should be specified as a pointer to the field. A field can be associated with multiple rules. For example, 

value := struct {
    Name  string
    Value string
}{"name", "demo"}
err := validation.ValidateStruct(&value,
    validation.Field(&a.Name, validation.Required),
    validation.Field(&a.Value, validation.Required, validation.Length(5, 10)),
)
fmt.Println(err)
// Value: the length must be between 5 and 10.

An error will be returned if validation fails.

func WithPrivilegeResolver 

func WithPrivilegeResolver(ctx context.Context, resolver PrivilegeResolver) context.Context

WithPrivilegeResolver adds a PrivilegeResolver to the context.

func WithThis 

func WithThis(ctx context.Context, this any) context.Context

func WithVisitContext 

func WithVisitContext(ctx context.Context, value interface{}) context.Context

Types

type BoolRule 

type BoolRule struct {
	// contains filtered or unexported fields
}

BoolRule is a validation rule that checks if a value bool.

func False 

func False(actual any) BoolRule

False returns a validation rule that checks if a value false. This rule should only be used for validating strings and byte slices, or a validation error will be reported. An empty value is considered valid. Use the Required rule to make sure a value is not empty.

func True 

func True(actual bool) BoolRule

True returns a validation rule that checks if a value true. This rule should only be used for validating strings and byte slices, or a validation error will be reported. An empty value is considered valid. Use the Required rule to make sure a value is not empty.

func (BoolRule) Error 

func (r BoolRule) Error(message string) BoolRule

Error sets the error message for the rule.

func (BoolRule) ErrorObject 

func (r BoolRule) ErrorObject(err Error) BoolRule

ErrorObject sets the error struct for the rule.

func (BoolRule) Validate 

func (r BoolRule) Validate(context.Context, interface{}) error

Validate checks if the given value is valid or not.

func (BoolRule) When 

func (r BoolRule) When(condition bool) BoolRule

When sets the condition that determines if the validation should be performed.

type Boolean 

type Boolean struct {
	Primitive[bool]
}

type CriteriaRule 

type CriteriaRule struct {
	// contains filtered or unexported fields
}

CriteriaRule is a validation rule that validates if a value match given value.

func Criteria 

func Criteria(expr string) CriteriaRule

Criteria returns a validation rule that checks if a value is match given value

func (CriteriaRule) Error 

func (r CriteriaRule) Error(message string) CriteriaRule

Error sets the error message for the rule.

func (CriteriaRule) ErrorObject 

func (r CriteriaRule) ErrorObject(err Error) CriteriaRule

ErrorObject sets the error struct for the rule.

func (*CriteriaRule) MarshalJSON 

func (r *CriteriaRule) MarshalJSON() ([]byte, error)

func (CriteriaRule) RuleType 

func (r CriteriaRule) RuleType() RuleType

func (*CriteriaRule) UnmarshalJSON 

func (r *CriteriaRule) UnmarshalJSON(data []byte) error

func (CriteriaRule) Validate 

func (r CriteriaRule) Validate(ctx context.Context, value interface{}) error

Validate checks if the given value is valid or not.

func (CriteriaRule) When 

func (r CriteriaRule) When(condition bool) CriteriaRule

When sets the condition that determines if the validation should be performed.

type DateRule 

type DateRule struct {
	// contains filtered or unexported fields
}

DateRule is a validation rule that validates date/time string values.

func Date 

func Date(layout string) DateRule

Date returns a validation rule that checks if a string value is in a format that can be parsed into a date. The format of the date should be specified as the layout parameter which accepts the same value as that for time.Parse. For example, 

validation.Date(time.ANSIC)
validation.Date("02 Jan 06 15:04 MST")
validation.Date("2006-01-02")

By calling Min() and/or Max(), you can let the Date rule to check if a parsed date value is within the specified date range.

An empty value is considered valid. Use the Required rule to make sure a value is not empty.

func (DateRule) Error 

func (r DateRule) Error(message string) DateRule

Error sets the error message that is used when the value being validated is not a valid date.

func (DateRule) ErrorObject 

func (r DateRule) ErrorObject(err Error) DateRule

ErrorObject sets the error struct that is used when the value being validated is not a valid date..

func (DateRule) MarshalJSON 

func (r DateRule) MarshalJSON() ([]byte, error)

func (DateRule) Max 

func (r DateRule) Max(max time.Time) DateRule

Max sets the maximum date range. A zero value means skipping the maximum range validation.

func (DateRule) Min 

func (r DateRule) Min(min time.Time) DateRule

Min sets the minimum date range. A zero value means skipping the minimum range validation.

func (DateRule) RangeError 

func (r DateRule) RangeError(message string) DateRule

RangeError sets the error message that is used when the value being validated is out of the specified Min/Max date range.

func (DateRule) RangeErrorObject 

func (r DateRule) RangeErrorObject(err Error) DateRule

RangeErrorObject sets the error struct that is used when the value being validated is out of the specified Min/Max date range.

func (DateRule) RuleType 

func (r DateRule) RuleType() RuleType

func (*DateRule) UnmarshalJSON 

func (r *DateRule) UnmarshalJSON(data []byte) error

UnmarshalJSON unmarshals the JSON data into the DateRule struct.

func (DateRule) Validate 

func (r DateRule) Validate(_ context.Context, value interface{}) error

Validate checks if the given value is a valid date.

func (DateRule) When 

func (r DateRule) When(condition bool) DateRule

When sets the condition that determines if the validation should be performed.

type Declarations 

type Declarations interface {
	DeclareInteger(key string, value int)
	DeclareFloat(key string, value float64)
	DeclareString(key string, value string)
	DeclareBool(key string, value bool)
	DeclareTime(key string, value time.Time)
}

type Declarator 

type Declarator interface {
	DeclareValidationFields(declarations Declarations)
}

type DependsOnRule 

type DependsOnRule struct {
	// contains filtered or unexported fields
}

DependsOnRule is a validation rule that executes the given list of rules dependsOn the condition is true.

func DependsOn 

func DependsOn(condition string, rules ...RuleEx) DependsOnRule

DependsOn returns a validation rule that executes the given list of rules dependsOn the condition is true.

func (DependsOnRule) Else 

func (r DependsOnRule) Else(rules ...RuleEx) DependsOnRule

Else returns a validation rule that executes the given list of rules dependsOn the condition is false.

func (*DependsOnRule) MarshalJSON 

func (r *DependsOnRule) MarshalJSON() ([]byte, error)

func (DependsOnRule) RuleType 

func (r DependsOnRule) RuleType() RuleType

func (*DependsOnRule) UnmarshalJSON 

func (r *DependsOnRule) UnmarshalJSON(data []byte) error

func (DependsOnRule) Validate 

func (r DependsOnRule) Validate(ctx context.Context, value interface{}) error

Validate checks if the condition is true and if so, it validates the value using the specified rules.

type EachRule 

type EachRule struct {
	// contains filtered or unexported fields
}

EachRule is a validation rule that validates elements in a map/slice/array using the specified list of rules.

func Each 

func Each(rules ...Rule) EachRule

Each returns a validation rule that loops through an iterable (map, slice or array) and validates each value inside with the provided rules. An empty iterable is considered valid. Use the Required rule to make sure the iterable is not empty.

func (EachRule) Key 

func (r EachRule) Key(rules ...Rule) EachRule

Key sets the rules to validate the keys of the map.

func (EachRule) Validate 

func (r EachRule) Validate(ctx context.Context, value interface{}) error

Validate loops through the given iterable and calls the Ozzo ValidateWithContext() method for each value.

func (EachRule) When 

func (r EachRule) When(condition bool) EachRule

When sets the condition that determines if the validation should be performed.

type ErrFieldNotFound 

type ErrFieldNotFound int

ErrFieldNotFound is the error that a field cannot be found in the struct.

func (ErrFieldNotFound) Error 

func (e ErrFieldNotFound) Error() string

Error returns the error string of ErrFieldNotFound.

type ErrFieldPointer 

type ErrFieldPointer int

ErrFieldPointer is the error that a field is not specified as a pointer.

func (ErrFieldPointer) Error 

func (e ErrFieldPointer) Error() string

Error returns the error string of ErrFieldPointer.

type Error 

type Error interface {
	Error() string
	Code() string
	Message() string
	Cause() error
	SetCode(string) Error
	SetMessage(string) Error
	SetCause(error) Error
	Params() map[string]interface{}
	SetParams(map[string]interface{}) Error
	AddParam(name string, value interface{}) Error
}

Error interface represents an validation error

func NewError 

func NewError(code, message string) Error

NewError create new validation error.

type ErrorDictionary 

type ErrorDictionary map[string]ErrorList

func (ErrorDictionary) Add 

func (d ErrorDictionary) Add(key string, err error)

func (ErrorDictionary) IsEmpty 

func (d ErrorDictionary) IsEmpty() bool

func (ErrorDictionary) ToErrors 

func (d ErrorDictionary) ToErrors() Errors

type ErrorLevel 

type ErrorLevel struct {
	Errors   ErrorList
	Children Errors
}

func EnsureLevel 

func EnsureLevel(err error) *ErrorLevel

EnsureLevel converts the given error into an ErrorLevel.

func NewErrorLevel 

func NewErrorLevel() *ErrorLevel

func (*ErrorLevel) AddChildError 

func (l *ErrorLevel) AddChildError(key string, err error) bool

func (*ErrorLevel) AddError 

func (l *ErrorLevel) AddError(err error) bool

func (*ErrorLevel) Error 

func (l *ErrorLevel) Error() string

func (*ErrorLevel) Is 

func (l *ErrorLevel) Is(target error) bool

func (*ErrorLevel) IsEmpty 

func (l *ErrorLevel) IsEmpty() bool

func (*ErrorLevel) MarshalJSON 

func (l *ErrorLevel) MarshalJSON() ([]byte, error)

func (*ErrorLevel) Merge 

func (l *ErrorLevel) Merge(other *ErrorLevel)

func (*ErrorLevel) Result 

func (l *ErrorLevel) Result() error

func (*ErrorLevel) Unwrap 

func (l *ErrorLevel) Unwrap() []error

func (*ErrorLevel) UpdateChildrenNamesByModelTags 

func (l *ErrorLevel) UpdateChildrenNamesByModelTags(model interface{})

func (*ErrorLevel) UpdateChildrenNamesByTypeTags 

func (l *ErrorLevel) UpdateChildrenNamesByTypeTags(typ reflect.Type)

type ErrorList 

type ErrorList []error

ErrorList represents a list of errors.

func (ErrorList) Error 

func (errs ErrorList) Error() string

func (ErrorList) Is 

func (errs ErrorList) Is(target error) bool

Is implements the errors.Is interface to check if the error matches a target error.

func (ErrorList) MarshalJSON 

func (errs ErrorList) MarshalJSON() ([]byte, error)

func (ErrorList) Unwrap 

func (errs ErrorList) Unwrap() []error

Unwrap returns a slice of errors contained in ErrorList.

type ErrorObject 

type ErrorObject struct {
	// contains filtered or unexported fields
}

ErrorObject is the default validation error that implements the Error interface.

func (ErrorObject) AddParam 

func (e ErrorObject) AddParam(name string, value interface{}) Error

AddParam add parameter to the error's parameters.

func (ErrorObject) Cause 

func (e ErrorObject) Cause() error

Cause returns the cause of the error, if any.

func (ErrorObject) Code 

func (e ErrorObject) Code() string

Code get the error's translation code.

func (ErrorObject) Error 

func (e ErrorObject) Error() string

Error returns the error message.

func (ErrorObject) Is 

func (e ErrorObject) Is(target error) bool

Is implements the errors.Is interface to check if the error matches a target error.

func (ErrorObject) Message 

func (e ErrorObject) Message() string

Message return the error's message.

func (ErrorObject) Params 

func (e ErrorObject) Params() map[string]interface{}

Params returns the error's params.

func (ErrorObject) SetCause 

func (e ErrorObject) SetCause(cause error) Error

SetCause sets the cause of the error.

func (ErrorObject) SetCode 

func (e ErrorObject) SetCode(code string) Error

SetCode set the error's translation code.

func (ErrorObject) SetMessage 

func (e ErrorObject) SetMessage(message string) Error

SetMessage set the error's message.

func (ErrorObject) SetParams 

func (e ErrorObject) SetParams(params map[string]interface{}) Error

SetParams set the error's params.

func (ErrorObject) Unwrap 

func (e ErrorObject) Unwrap() []error

type Errors 

type Errors map[string]error

Errors represents the validation errors that are indexed by struct field names, map or slice keys. values are Error or Errors (for map, slice and array error value is Errors).

func (Errors) Error 

func (es Errors) Error() string

Error returns the error string of Errors.

func (Errors) Filter 

func (es Errors) Filter() error

Filter removes all nils from Errors and returns back the updated Errors as an error. If the length of Errors becomes 0, it will return nil.

func (Errors) Is 

func (es Errors) Is(target error) bool

Is implements the errors.Is interface to check if the error matches a target error.

func (Errors) MarshalJSON 

func (es Errors) MarshalJSON() ([]byte, error)

MarshalJSON converts the Errors into a valid JSON.

func (Errors) Unwrap 

func (es Errors) Unwrap() []error

Unwrap returns a slice of errors contained in Errors.

type FieldRules 

type FieldRules struct {
	// contains filtered or unexported fields
}

FieldRules represents a rule set associated with a struct field.

func Field 

func Field(fieldPtr interface{}, rules ...Rule) *FieldRules

Field specifies a struct field and the corresponding validation rules. The struct field must be specified as a pointer to it.

func Integrity 

func Integrity(rules ...Rule) *FieldRules

Integrity creates a FieldRules that is used to validate the integrity of a struct whole.

type Float 

type Float struct {
	Primitive[float64]
}

type InRule 

type InRule struct {
	// contains filtered or unexported fields
}

InRule is a validation rule that validates if a value can be found in the given list of values.

func In 

func In(values ...interface{}) InRule

In returns a validation rule that checks if a value can be found in the given list of values. reflect.DeepEqual() will be used to determine if two values are equal. For more details please refer to https://golang.org/pkg/reflect/#DeepEqual An empty value is considered valid. Use the Required rule to make sure a value is not empty.

func (InRule) Error 

func (r InRule) Error(message string) InRule

Error sets the error message for the rule.

func (InRule) ErrorObject 

func (r InRule) ErrorObject(err Error) InRule

ErrorObject sets the error struct for the rule.

func (*InRule) MarshalJSON 

func (r *InRule) MarshalJSON() ([]byte, error)

func (InRule) RuleType 

func (r InRule) RuleType() RuleType

func (*InRule) UnmarshalJSON 

func (r *InRule) UnmarshalJSON(data []byte) error

func (InRule) Validate 

func (r InRule) Validate(_ context.Context, value interface{}) error

Validate checks if the given value is valid or not.

func (InRule) When 

func (r InRule) When(condition bool) InRule

When sets the condition that determines if the validation should be performed.

type Integer 

type Integer struct {
	Primitive[int64]
}

type InternalError 

type InternalError interface {
	error
	InternalError() error
}

InternalError represents an error that should NOT be treated as a validation error.

func NewInternalError 

func NewInternalError(err error) InternalError

NewInternalError wraps a given error into an InternalError.

type JsonRule 

type JsonRule struct {
	// contains filtered or unexported fields
}

JsonRule is a validation rule that valijsons json/time string values.

func Json 

func Json(schema JsonSchema) JsonRule

func (JsonRule) Error 

func (r JsonRule) Error(message string) JsonRule

Error sets the error message that is used when the value being valijsond is not a valid json.

func (JsonRule) ErrorObject 

func (r JsonRule) ErrorObject(err Error) JsonRule

ErrorObject sets the error struct that is used when the value being valijsond is not a valid json..

func (JsonRule) Validate 

func (r JsonRule) Validate(ctx context.Context, value interface{}) error

Validate checks if the given value is a valid json.

func (JsonRule) When 

func (r JsonRule) When(condition bool) JsonRule

When sets the condition that determines if the validation should be performed.

type JsonSchema 

type JsonSchema interface {
	Validate(ctx context.Context, value interface{}) error
}

JsonSchema is an interface that defines a method for validating JSON values. It may be implemented by any type that can validate JSON data. For example: github.com/santhosh-tekuri/jsonschema/v5

type KeyRules 

type KeyRules struct {
	// contains filtered or unexported fields
}

KeyRules represents a rule set associated with a map key.

func Key 

func Key(key interface{}, rules ...Rule) *KeyRules

Key specifies a map key and the corresponding validation rules.

func (*KeyRules) Optional 

func (r *KeyRules) Optional() *KeyRules

Optional configures the rule to ignore the key if missing.

func (*KeyRules) Validate 

func (r *KeyRules) Validate(ctx context.Context, m interface{}) error

type LengthRule 

type LengthRule struct {
	// contains filtered or unexported fields
}

LengthRule is a validation rule that checks if a value's length is within the specified range.

func Length 

func Length(min, max int) LengthRule

Length returns a validation rule that checks if a value's length is within the specified range. If max is 0, it means there is no upper bound for the length. This rule should only be used for validating strings, slices, maps, and arrays. An empty value is considered valid. Use the Required rule to make sure a value is not empty.

func RuneLength 

func RuneLength(min, max int) LengthRule

RuneLength returns a validation rule that checks if a string's rune length is within the specified range. If max is 0, it means there is no upper bound for the length. This rule should only be used for validating strings, slices, maps, and arrays. An empty value is considered valid. Use the Required rule to make sure a value is not empty. If the value being validated is not a string, the rule works the same as Length.

func (LengthRule) Error 

func (r LengthRule) Error(message string) LengthRule

Error sets the error message for the rule.

func (LengthRule) ErrorObject 

func (r LengthRule) ErrorObject(err Error) LengthRule

ErrorObject sets the error struct for the rule.

func (*LengthRule) MarshalJSON 

func (r *LengthRule) MarshalJSON() ([]byte, error)

func (LengthRule) RuleType 

func (r LengthRule) RuleType() RuleType

func (*LengthRule) UnmarshalJSON 

func (r *LengthRule) UnmarshalJSON(data []byte) error

func (LengthRule) Validate 

func (r LengthRule) Validate(_ context.Context, value interface{}) error

Validate checks if the given value is valid or not.

func (LengthRule) When 

func (r LengthRule) When(condition bool) LengthRule

When sets the condition that determines if the validation should be performed.

type MatchRule 

type MatchRule struct {
	// contains filtered or unexported fields
}

MatchRule is a validation rule that checks if a value matches the specified regular expression.

func Match 

func Match(re *regexp.Regexp) MatchRule

Match returns a validation rule that checks if a value matches the specified regular expression. This rule should only be used for validating strings and byte slices, or a validation error will be reported. An empty value is considered valid. Use the Required rule to make sure a value is not empty.

func (MatchRule) Error 

func (r MatchRule) Error(message string) MatchRule

Error sets the error message for the rule.

func (MatchRule) ErrorObject 

func (r MatchRule) ErrorObject(err Error) MatchRule

ErrorObject sets the error struct for the rule.

func (*MatchRule) MarshalJSON 

func (r *MatchRule) MarshalJSON() ([]byte, error)

func (MatchRule) RuleType 

func (r MatchRule) RuleType() RuleType

func (*MatchRule) UnmarshalJSON 

func (r *MatchRule) UnmarshalJSON(data []byte) error

func (MatchRule) Validate 

func (r MatchRule) Validate(_ context.Context, value interface{}) error

Validate checks if the given value is valid or not.

func (MatchRule) When 

func (r MatchRule) When(condition bool) MatchRule

When sets the condition that determines if the validation should be performed.

type MultipleOfRule 

type MultipleOfRule struct {
	// contains filtered or unexported fields
}

MultipleOfRule is a validation rule that checks if a value is a multiple of the "base" value.

func MultipleOf 

func MultipleOf(base interface{}) MultipleOfRule

MultipleOf returns a validation rule that checks if a value is a multiple of the "base" value. Note that "base" should be of integer type.

func (MultipleOfRule) Error 

func (r MultipleOfRule) Error(message string) MultipleOfRule

Error sets the error message for the rule.

func (MultipleOfRule) ErrorObject 

func (r MultipleOfRule) ErrorObject(err Error) MultipleOfRule

ErrorObject sets the error struct for the rule.

func (MultipleOfRule) MarshalJSON 

func (r MultipleOfRule) MarshalJSON() ([]byte, error)

func (MultipleOfRule) RuleType 

func (r MultipleOfRule) RuleType() RuleType

func (*MultipleOfRule) UnmarshalJSON 

func (r *MultipleOfRule) UnmarshalJSON(data []byte) error

func (MultipleOfRule) Validate 

func (r MultipleOfRule) Validate(_ context.Context, value interface{}) error

Validate checks if the value is a multiple of the "base" value.

func (MultipleOfRule) When 

func (r MultipleOfRule) When(condition bool) MultipleOfRule

When sets the condition that determines if the validation should be performed.

type NotInRule 

type NotInRule struct {
	// contains filtered or unexported fields
}

NotInRule is a validation rule that checks if a value is absent from the given list of values.

func NotIn 

func NotIn(values ...interface{}) NotInRule

NotIn returns a validation rule that checks if a value is absent from the given list of values. Note that the value being checked and the possible range of values must be of the same type. An empty value is considered valid. Use the Required rule to make sure a value is not empty.

func (NotInRule) Error 

func (r NotInRule) Error(message string) NotInRule

Error sets the error message for the rule.

func (NotInRule) ErrorObject 

func (r NotInRule) ErrorObject(err Error) NotInRule

ErrorObject sets the error struct for the rule.

func (NotInRule) MarshalJSON 

func (r NotInRule) MarshalJSON() ([]byte, error)

func (NotInRule) RuleType 

func (r NotInRule) RuleType() RuleType

func (*NotInRule) UnmarshalJSON 

func (r *NotInRule) UnmarshalJSON(data []byte) error

func (NotInRule) Validate 

func (r NotInRule) Validate(_ context.Context, value interface{}) error

Validate checks if the given value is valid or not.

func (NotInRule) When 

func (r NotInRule) When(condition bool) NotInRule

When sets the condition that determines if the validation should be performed.

type Primitive 

type Primitive[T any] struct {
	Value T
	Valid bool
	Error error
}

func (*Primitive[T]) GetName 

func (that *Primitive[T]) GetName() string

func (*Primitive[T]) GetValue 

func (that *Primitive[T]) GetValue() interface{}

func (*Primitive[T]) MarshalJSON 

func (that *Primitive[T]) MarshalJSON() ([]byte, error)

func (*Primitive[T]) UnmarshalJSON 

func (that *Primitive[T]) UnmarshalJSON(data []byte) error

func (*Primitive[T]) Validate 

func (that *Primitive[T]) Validate(ctx context.Context) error

type PrivilegeResolver 

type PrivilegeResolver interface {
	HasPrivilege(ctx context.Context, resource, action string) (bool, error)
}

func GetPrivilegeResolver 

func GetPrivilegeResolver(ctx context.Context) PrivilegeResolver

GetPrivilegeResolver retrieves the PrivilegeResolver from the context.

type PrivilegeRule 

type PrivilegeRule struct {
	// contains filtered or unexported fields
}

PrivilegeRule checks if the user has the required privilege.

func Privilege 

func Privilege(
	resource string,
	action string,
) PrivilegeRule

Privilege is a constructor for a privilege validation rule.

func (PrivilegeRule) Error 

func (that PrivilegeRule) Error(message string) PrivilegeRule

Error sets the error message for the rule.

func (PrivilegeRule) ErrorObject 

func (that PrivilegeRule) ErrorObject(err Error) PrivilegeRule

ErrorObject sets the error struct for the rule.

func (PrivilegeRule) Validate 

func (that PrivilegeRule) Validate(ctx context.Context, value interface{}) error

func (PrivilegeRule) When 

func (that PrivilegeRule) When(condition bool) PrivilegeRule

When sets the condition that determines if the validation should be performed.

type RequiredRule 

type RequiredRule struct {
	// contains filtered or unexported fields
}

RequiredRule is a rule that checks if a value is not empty.

func (RequiredRule) Error 

func (r RequiredRule) Error(message string) RequiredRule

Error sets the error message for the rule.

func (RequiredRule) ErrorObject 

func (r RequiredRule) ErrorObject(err Error) RequiredRule

ErrorObject sets the error struct for the rule.

func (*RequiredRule) MarshalJSON 

func (r *RequiredRule) MarshalJSON() ([]byte, error)

func (RequiredRule) RuleType 

func (r RequiredRule) RuleType() RuleType

func (*RequiredRule) UnmarshalJSON 

func (r *RequiredRule) UnmarshalJSON(data []byte) error

func (RequiredRule) Validate 

func (r RequiredRule) Validate(_ context.Context, value interface{}) error

Validate checks if the given value is valid or not.

func (RequiredRule) When 

func (r RequiredRule) When(condition bool) RequiredRule

When sets the condition that determines if the validation should be performed.

type Rule 

type Rule interface {
	// Validate validates a value and returns a value if validation fails.
	Validate(ctx context.Context, value interface{}) error
}

Rule represents a validation rule.

func By 

func By(f RuleFunc) Rule

By wraps a RuleFunc into a Rule.

type RuleEx 

type RuleEx interface {
	RuleType() RuleType
	json.Marshaler
	json.Unmarshaler
	Rule
}

RuleEx is an extended Rule interface that includes a Type method to return the type of the rule. You must use it for serialization purposes.

func UnmarshalRule 

func UnmarshalRule(data []byte) (RuleEx, error)

func UnmarshalRules 

func UnmarshalRules(data []byte) (rules []RuleEx, err error)

func UnmarshalTypedRule 

func UnmarshalTypedRule(data []byte, ruleType RuleType) (RuleEx, error)

type RuleExs 

type RuleExs []RuleEx

func (RuleExs) MarshalJSON 

func (r RuleExs) MarshalJSON() ([]byte, error)

func (*RuleExs) UnmarshalJSON 

func (r *RuleExs) UnmarshalJSON(data []byte) error

type RuleFunc 

type RuleFunc func(ctx context.Context, value interface{}) error

RuleFunc represents a validator function. You may wrap it as a Rule by calling By().

type RuleType 

type RuleType string
const (
	RuleTypeNil   RuleType = "nil"
	RuleTypeEmpty RuleType = "empty"
)
const (
	RuleTypeCriteria RuleType = "criteria"
)
const (
	RuleTypeIn RuleType = "in"
)
const (
	RuleTypeLength RuleType = "length"
)
const (
	RuleTypeType RuleType = "type"
)
const (
	ThresholdRuleType RuleType = "threshold"
)

type String 

type String struct {
	Primitive[string]
}

type StringRule 

type StringRule struct {
	// contains filtered or unexported fields
}

StringRule is a rule that checks a string variable using a specified stringValidator.

func NewStringRule 

func NewStringRule(t RuleType, validator stringValidator, message string) StringRule

NewStringRule creates a new validation rule using a function that takes a string value and returns a bool. The rule returned will use the function to check if a given string or byte slice is valid or not. An empty value is considered to be valid. Please use the Required rule to make sure a value is not empty.

func NewStringRuleWithError 

func NewStringRuleWithError(t RuleType, validator stringValidator, err Error) StringRule

NewStringRuleWithError creates a new validation rule using a function that takes a string value and returns a bool. The rule returned will use the function to check if a given string or byte slice is valid or not. An empty value is considered to be valid. Please use the Required rule to make sure a value is not empty.

func (StringRule) Error 

func (r StringRule) Error(message string) StringRule

Error sets the error message for the rule.

func (StringRule) ErrorObject 

func (r StringRule) ErrorObject(err Error) StringRule

ErrorObject sets the error struct for the rule.

func (StringRule) MarshalJSON 

func (r StringRule) MarshalJSON() ([]byte, error)

func (StringRule) RuleType 

func (r StringRule) RuleType() RuleType

func (StringRule) UnmarshalJSON 

func (r StringRule) UnmarshalJSON(data []byte) error

func (StringRule) Validate 

func (r StringRule) Validate(_ context.Context, value interface{}) error

Validate checks if the given value is valid or not.

func (StringRule) When 

func (r StringRule) When(condition bool) StringRule

When sets the condition that determines if the validation should be performed.

type ThresholdRule 

type ThresholdRule struct {
	// contains filtered or unexported fields
}

ThresholdRule is a validation rule that checks if a value satisfies the specified threshold requirement.

func Max 

func Max(max interface{}) ThresholdRule

Max returns a validation rule that checks if a value is less or equal than the specified value. By calling Exclusive, the rule will check if the value is strictly less than the specified value. Note that the value being checked and the threshold value must be of the same type. Only int, uint, float and time.Time types are supported. An empty value is considered valid. Please use the Required rule to make sure a value is not empty.

func Min 

func Min(min interface{}) ThresholdRule

Min returns a validation rule that checks if a value is greater or equal than the specified value. By calling Exclusive, the rule will check if the value is strictly greater than the specified value. Note that the value being checked and the threshold value must be of the same type. Only int, uint, float and time.Time types are supported. An empty value is considered valid. Please use the Required rule to make sure a value is not empty.

func (ThresholdRule) Error 

func (r ThresholdRule) Error(message string) ThresholdRule

Error sets the error message for the rule.

func (ThresholdRule) ErrorObject 

func (r ThresholdRule) ErrorObject(err Error) ThresholdRule

ErrorObject sets the error struct for the rule.

func (ThresholdRule) Exclusive 

func (r ThresholdRule) Exclusive() ThresholdRule

Exclusive sets the comparison to exclude the boundary value.

func (ThresholdRule) MarshalJSON 

func (r ThresholdRule) MarshalJSON() ([]byte, error)

func (ThresholdRule) RuleType 

func (r ThresholdRule) RuleType() RuleType

func (*ThresholdRule) UnmarshalJSON 

func (r *ThresholdRule) UnmarshalJSON(data []byte) error

func (ThresholdRule) Validate 

func (r ThresholdRule) Validate(_ context.Context, value interface{}) error

Validate checks if the given value is valid or not.

func (ThresholdRule) When 

func (r ThresholdRule) When(condition bool) ThresholdRule

When sets the condition that determines if the validation should be performed.

type TypeRule 

type TypeRule struct {
	// contains filtered or unexported fields
}

TypeRule is a validation rule that validates if a value has one of given list names of types.

func Type 

func Type(types ...string) TypeRule

Type returns a validation rule that checks if a value is match required type. reflect.DeepEqual() will be used to determine if two values are equal. For more details please refer to https://golang.org/pkg/reflect/#DeepEqual An empty value is considered valid. Use the Required rule to make sure a value is not empty.

func (TypeRule) Error 

func (r TypeRule) Error(message string) TypeRule

Error sets the error message for the rule.

func (TypeRule) ErrorObject 

func (r TypeRule) ErrorObject(err Error) TypeRule

ErrorObject sets the error struct for the rule.

func (*TypeRule) MarshalJSON 

func (r *TypeRule) MarshalJSON() ([]byte, error)

func (TypeRule) RuleType 

func (r TypeRule) RuleType() RuleType

func (*TypeRule) UnmarshalJSON 

func (r *TypeRule) UnmarshalJSON(data []byte) error

func (TypeRule) Validate 

func (r TypeRule) Validate(_ context.Context, value interface{}) error

Validate checks if the given value is valid or not.

func (TypeRule) When 

func (r TypeRule) When(condition bool) TypeRule

When sets the condition that determines if the validation should be performed.

type UnchangeableRule 

type UnchangeableRule struct {
	// contains filtered or unexported fields
}

UnchangeableRule is a validation rule that checks if a value unchangeable.

func Unchangeable 

func Unchangeable(original any) UnchangeableRule

Unchangeable returns a validation rule that checks if a value unchangeable. This rule should only be used for validating strings and byte slices, or a validation error will be reported. An empty value is considered valid. Use the Required rule to make sure a value is not empty.

func (UnchangeableRule) Error 

func (r UnchangeableRule) Error(message string) UnchangeableRule

Error sets the error message for the rule.

func (UnchangeableRule) ErrorObject 

func (r UnchangeableRule) ErrorObject(err Error) UnchangeableRule

ErrorObject sets the error struct for the rule.

func (UnchangeableRule) Validate 

func (r UnchangeableRule) Validate(_ context.Context, value interface{}) error

Validate checks if the given value is valid or not.

func (UnchangeableRule) When 

func (r UnchangeableRule) When(condition bool) UnchangeableRule

When sets the condition that determines if the validation should be performed.

type UniqueListRule 

type UniqueListRule struct {
	// contains filtered or unexported fields
}

UniqueListRule is a validation rule that validates if a value can be unique in the given list of values.

func UniqueList 

func UniqueList() UniqueListRule

UniqueList returns a validation rule that checks if a value can be unique in the given list of values. reflect.DeepEqual() will be used to determine if two values are equal. For more details please refer to https://golang.org/pkg/reflect/#DeepEqual An empty value is considered valid. Use the Required rule to make sure a value is not empty.

func (UniqueListRule) Error 

func (r UniqueListRule) Error(message string) UniqueListRule

Error sets the error message for the rule.

func (UniqueListRule) ErrorObject 

func (r UniqueListRule) ErrorObject(err Error) UniqueListRule

ErrorObject sets the error struct for the rule.

func (UniqueListRule) Validate 

func (r UniqueListRule) Validate(_ context.Context, value interface{}) error

Validate checks if the given value is valid or not.

func (UniqueListRule) When 

func (r UniqueListRule) When(condition bool) UniqueListRule

When sets the condition that determines if the validation should be performed.

type UniqueRule 

type UniqueRule struct {
	// contains filtered or unexported fields
}

UniqueRule is a validation rule that validates if a value can be unique in the given list of values.

func Unique 

func Unique(values ...interface{}) UniqueRule

Unique returns a validation rule that checks if a value can be unique in the given list of values. reflect.DeepEqual() will be used to determine if two values are equal. For more details please refer to https://golang.org/pkg/reflect/#DeepEqual An empty value is considered valid. Use the Required rule to make sure a value is not empty.

func (UniqueRule) Error 

func (r UniqueRule) Error(message string) UniqueRule

Error sets the error message for the rule.

func (UniqueRule) ErrorObject 

func (r UniqueRule) ErrorObject(err Error) UniqueRule

ErrorObject sets the error struct for the rule.

func (UniqueRule) Validate 

func (r UniqueRule) Validate(_ context.Context, value interface{}) error

Validate checks if the given value is valid or not.

func (UniqueRule) When 

func (r UniqueRule) When(condition bool) UniqueRule

When sets the condition that determines if the validation should be performed.

type Unmarshaller 

type Unmarshaller func(data []byte) (RuleEx, error)

type Validatable 

type Validatable interface {
	// Validate validates the data and returns an error if validation fails.
	Validate(ctx context.Context) error
}

Validatable is the interface indicating the type implementing it supports data validation.

type ValidatorDTO 

type ValidatorDTO struct {
	Type string          `json:"type"`
	Data json.RawMessage `json:"data"`
}

type Valuable 

type Valuable interface {
	// GetValue returns the value of the object.
	GetValue() interface{}
}

Valuable is the interface indicating the type implementing it can return its value.

type WhenRule 

type WhenRule struct {
	// contains filtered or unexported fields
}

WhenRule is a validation rule that executes the given list of rules when the condition is true.

func When 

func When(condition bool, rules ...Rule) WhenRule

When returns a validation rule that executes the given list of rules when the condition is true.

func (WhenRule) Else 

func (r WhenRule) Else(rules ...Rule) WhenRule

Else returns a validation rule that executes the given list of rules when the condition is false.

func (WhenRule) Validate 

func (r WhenRule) Validate(ctx context.Context, value interface{}) error

Validate checks if the condition is true and if so, it validates the value using the specified rules.

Source Files

View all Source files

Directories

Path Synopsis
Package is provides a list of commonly used string validation rules.
 Package is provides a list of commonly used string validation rules.

Jump to

Keyboard shortcuts

? : This menu
/ : Search site
f or F : Jump to
y or Y : Canonical URL
go.dev uses cookies from Google to deliver and enhance the quality of its services and to analyze traffic. Learn more.