import "github.com/go-ozzo/ozzo-validation"
Package validation provides configurable and extensible rules for validating data of various types.
Code:
c := Customer{
Name: "Qiang Xue",
Email: "q",
Address: Address{
Street: "123 Main Street",
City: "Unknown",
State: "Virginia",
Zip: "12345",
},
}
err := c.Validate()
fmt.Println(err)
Output:
Address: (State: must be in a valid format.); Email: must be a valid email address.
Code:
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.
Code:
c := Customer{
Name: "Qiang Xue",
Email: "q",
Address: Address{
State: "Virginia",
},
}
err := validation.Errors{
"name": validation.Validate(c.Name, validation.Required, validation.Length(5, 20)),
"email": validation.Validate(c.Name, validation.Required, is.Email),
"zip": validation.Validate(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.
Code:
data := "example"
err := validation.Validate(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
Code:
key := contextKey(1)
rule := validation.WithContext(func(ctx context.Context, value interface{}) error {
s, _ := value.(string)
if ctx.Value(key) == s {
return nil
}
return errors.New("unexpected value")
})
ctx := context.WithValue(context.Background(), key, "good sample")
err1 := validation.ValidateWithContext(ctx, "bad sample", rule)
fmt.Println(err1)
err2 := validation.ValidateWithContext(ctx, "good sample", rule)
fmt.Println(err2)
Output:
unexpected value <nil>
Code:
addresses := []Address{
{State: "MD", Zip: "12345"},
{Street: "123 Main St", City: "Vienna", State: "VA", Zip: "12345"},
{City: "Unknown", State: "NC", Zip: "123"},
}
err := validation.Validate(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.).
absent.go date.go each.go error.go in.go length.go match.go minmax.go multipleof.go not_in.go not_nil.go required.go string.go struct.go util.go validation.go when.go
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")
)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")
)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")
)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}}")
)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")
)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{}
)var Empty = absentRule{/* contains filtered or unexported fields */}
Empty checks if a not nil value is empty.
ErrInInvalid is the error that returns in case of an invalid value for "in" rule.
ErrMatchInvalid is the error that returns in case of invalid format.
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.
ErrNotInInvalid is the error that returns when a value is in a list.
ErrNotNilRequired is the error that returns when a value is Nil.
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")
)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
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.
var NotNil = notNilRule{}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.
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
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.
Indirect returns the value that the given interface or pointer references to. If the value implements driver.Valuer, it will deal with the value returned by the Value() method instead. 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.
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
LengthOfValue returns the length of a value that is a string, slice, map, or array. An error is returned for all other types.
StringOrBytes typecasts a value into a string or byte slice. Boolean flags are returned to indicate if the typecasting succeeds or not.
ToFloat converts the given value to a float64. An error is returned for all incompatible types.
ToInt converts the given value to an int64. An error is returned for all incompatible types.
ToUint converts the given value to an uint64. An error is returned for all incompatible types.
Validate validates the given value and returns the validation error, if any.
Validate performs validation using the following steps: 1. For each rule, call its `Validate()` to validate the value. Return if any error is found. 2. If the value being validated implements `Validatable`, call the value's `Validate()`.
Return with the validation result.
3. 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(structPtr interface{}, fields ...*FieldRules) errorValidateStruct 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 ValidateStructWithContext(ctx context.Context, structPtr interface{}, fields ...*FieldRules) error
ValidateStructWithContext validates a struct with the given context. The only difference between ValidateStructWithContext and ValidateStruct is that the former will validate struct fields with the provided context. Please refer to ValidateStruct for the detailed instructions on how to use this function.
ValidateWithContext validates the given value with the given context and returns the validation error, if any.
ValidateWithContext 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 `ValidatableWithContext`,
for each element call the element value's `ValidateWithContext()`. Return with the validation result.
5. 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.
type DateRule struct {
// contains filtered or unexported fields
}DateRule is a validation rule that validates date/time string values.
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.
Error sets the error message that is used when the value being validated is not a valid date.
ErrorObject sets the error struct that is used when the value being validated is not a valid date..
Max sets the maximum date range. A zero value means skipping the maximum range validation.
Min sets the minimum date range. A zero value means skipping the minimum range validation.
RangeError sets the error message that is used when the value being validated is out of the specified Min/Max date range.
RangeErrorObject sets the error struct that is used when the value being validated is out of the specified Min/Max date range.
Validate checks if the given value is a valid date.
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.
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.
Validate loops through the given iterable and calls the Ozzo Validate() method for each value.
ErrFieldNotFound is the error that a field cannot be found in the struct.
func (e ErrFieldNotFound) Error() string
Error returns the error string of ErrFieldNotFound.
ErrFieldPointer is the error that a field is not specified as a pointer.
func (e ErrFieldPointer) Error() string
Error returns the error string of ErrFieldPointer.
type Error interface {
Error() string
Code() string
Message() string
SetMessage(string) Error
Params() map[string]interface{}
SetParams(map[string]interface{}) Error
}Error interface represents an validation error
NewError create new validation error.
type ErrorObject struct {
// contains filtered or unexported fields
}ErrorObject is the default validation error that implements the Error interface.
func (e ErrorObject) AddParam(name string, value interface{}) Error
AddParam add parameter to the error's parameters.
func (e ErrorObject) Code() string
Code get the error's translation code.
func (e ErrorObject) Error() string
Error returns the error message.
func (e ErrorObject) Message() string
Message return the error's message.
func (e ErrorObject) Params() map[string]interface{}
Params returns the error's params.
func (e ErrorObject) SetCode(code string) Error
SetCode set the error's translation code.
func (e ErrorObject) SetMessage(message string) Error
SetMessage set the error's message.
func (e ErrorObject) SetParams(params map[string]interface{}) Error
SetParams set the error's params.
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).
Error returns the error string of Errors.
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.
MarshalJSON converts the Errors into a valid JSON.
type FieldRules struct {
// contains filtered or unexported fields
}FieldRules represents a rule set associated with a struct field.
func Field(fieldPtr interface{}, rules ...Rule) *FieldRulesField specifies a struct field and the corresponding validation rules. The struct field must be specified as a pointer to it.
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.
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.
Error sets the error message for the rule.
ErrorObject sets the error struct for the rule.
Validate checks if the given value is valid or not.
InternalError represents an error that should NOT be treated as a validation error.
func NewInternalError(err error) InternalError
NewInternalError wraps a given error into an InternalError.
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(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(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 (r LengthRule) Error(message string) LengthRule
Error sets the error message for the rule.
func (r LengthRule) ErrorObject(err Error) LengthRule
ErrorObject sets the error struct for the rule.
func (r LengthRule) Validate(value interface{}) error
Validate checks if the given value is valid or not.
type MatchRule struct {
// contains filtered or unexported fields
}MatchRule is a validation rule that checks if a value matches the specified regular expression.
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.
Error sets the error message for the rule.
ErrorObject sets the error struct for the rule.
Validate checks if the given value is valid or not.
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(base interface{}) MultipleOfRuleMultipleOf 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 (r MultipleOfRule) Error(message string) MultipleOfRule
Error sets the error message for the rule.
func (r MultipleOfRule) ErrorObject(err Error) MultipleOfRule
ErrorObject sets the error struct for the rule.
func (r MultipleOfRule) Validate(value interface{}) error
Validate checks if the value is a multiple of the "base" value.
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.
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.
Error sets the error message for the rule.
ErrorObject sets the error struct for the rule.
Validate checks if the given value is valid or not.
type RequiredRule struct {
// contains filtered or unexported fields
}RequiredRule is a rule that checks if a value is not empty.
func (r RequiredRule) Error(message string) RequiredRule
Error sets the error message for the rule.
func (r RequiredRule) ErrorObject(err Error) RequiredRule
ErrorObject sets the error struct for the rule.
func (r RequiredRule) Validate(value interface{}) error
Validate checks if the given value is valid or not.
func (r RequiredRule) When(condition bool) RequiredRule
When sets the condition that determines if the validation should be performed.
type Rule interface {
// Validate validates a value and returns a value if validation fails.
Validate(value interface{}) error
}Rule represents a validation rule.
By wraps a RuleFunc into a Rule.
func WithContext(f RuleWithContextFunc) Rule
WithContext wraps a RuleWithContextFunc into a context-aware Rule.
RuleFunc represents a validator function. You may wrap it as a Rule by calling By().
type RuleWithContext interface {
// ValidateWithContext validates a value and returns a value if validation fails.
ValidateWithContext(ctx context.Context, value interface{}) error
}RuleWithContext represents a context-aware validation rule.
RuleWithContextFunc represents a validator function that is context-aware. You may wrap it as a Rule by calling WithContext().
type StringRule struct {
// contains filtered or unexported fields
}StringRule is a rule that checks a string variable using a specified stringValidator.
func NewStringRule(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(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 (r StringRule) Error(message string) StringRule
Error sets the error message for the rule.
func (r StringRule) ErrorObject(err Error) StringRule
ErrorObject sets the error struct for the rule.
func (r StringRule) Validate(value interface{}) error
Validate checks if the given value is valid or not.
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(max interface{}) ThresholdRuleMax 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(min interface{}) ThresholdRuleMin 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 (r ThresholdRule) Error(message string) ThresholdRule
Error sets the error message for the rule.
func (r ThresholdRule) ErrorObject(err Error) ThresholdRule
ErrorObject sets the error struct for the rule.
func (r ThresholdRule) Exclusive() ThresholdRule
Exclusive sets the comparison to exclude the boundary value.
func (r ThresholdRule) Validate(value interface{}) error
Validate checks if the given value is valid or not.
type Validatable interface {
// Validate validates the data and returns an error if validation fails.
Validate() error
}Validatable is the interface indicating the type implementing it supports data validation.
type ValidatableWithContext interface {
// ValidateWithContext validates the data with the given context and returns an error if validation fails.
ValidateWithContext(ctx context.Context) error
}ValidatableWithContext is the interface indicating the type implementing it supports context-aware data validation.
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.
When returns a validation rule that executes the given list of rules when the condition is true.
Else returns a validation rule that executes the given list of rules when the condition is false.
Validate checks if the condition is true and if so, it validates the value using the specified rules.
| Path | Synopsis |
|---|---|
| is | Package is provides a list of commonly used string validation rules. |
Package validation imports 14 packages (graph) and is imported by 244 packages. Updated 2020-05-28. Refresh now. Tools for package owners.