fender

README

fender

a piece of rope or a tyre that protects the side of a boat from knocks

Fender provides a unified way to validate data and make the errors passable to the frontend e.g. through gotsrpc.

Usage

Fender provides different ways to validate your data.

struct validation using go-playground validator

package main

import (
	"fmt"

	"github.com/foomo/fender"
)

type Test struct {
	Int     int     `validate:"min=1"`
	Int8    int8    `validate:"min=1"`
	Int32   int32   `validate:"min=1"`
	Int64   int64   `validate:"min=1"`
	UInt    uint    `validate:"min=1"`
	UInt8   uint8   `validate:"min=1"`
	UInt32  uint32  `validate:"min=1"`
	UInt64  uint64  `validate:"min=1"`
	Float32 float32 `validate:"min=1.5"`
	Float64 float64 `validate:"min=1.5"`
	Bool    bool    `validate:"required"`
	String  string  `validate:"required"`
}

func main() {
	u := Test{}
	fendErr, err := fender.Struct(u)
	if err != nil {
		panic("internal error: " + err.Error())
	}
	fmt.Println(fendErr) // bool:required;string:required;uInt:min=1;uInt8:min=1;uInt32:min=1;uInt64:min=1;float32:min=1.5;int:min=1;int8:min=1;int32:min=1;int64:min=1;float64:min=1.5
}

validate by code

package main

import (
	"fmt"

	"github.com/foomo/fender"
	"github.com/foomo/fender/fend"
	"github.com/foomo/fender/rule"
)

type Test struct {
	Int     int
	Int8    int8
	Int32   int32
	Int64   int64
	UInt    uint
	UInt8   uint8
	UInt32  uint32
	UInt64  uint64
	Float32 float32
	Float64 float64
	Bool    bool
	String  string
}

func main() {
	u := Test{}
	fendErr, err := fender.All(
		fender.Field("int", fend.Int(u.Int, rule.MinInt(1))),
		fender.Field("int8", fend.Int8(u.Int8, rule.MinInt8(1))),
		fender.Field("int32", fend.Int32(u.Int32, rule.MinInt32(1))),
		fender.Field("int64", fend.Int64(u.Int64, rule.MinInt64(1))),
		fender.Field("uint", fend.UInt(u.UInt, rule.MinUInt(1))),
		fender.Field("uint8", fend.UInt8(u.UInt8, rule.MinUInt8(1))),
		fender.Field("uint32", fend.UInt32(u.UInt32, rule.MinUInt32(1))),
		fender.Field("uint64", fend.UInt64(u.UInt64, rule.MinUInt64(1))),
		fender.Field("float32", fend.Float32(u.Float32, rule.MinFloat32(1.5))),
		fender.Field("float64", fend.Float64(u.Float64, rule.MinFloat64(1.5))),
		fender.Field("bool", fend.Bool(u.Bool, rule.Bool(true))),
		fender.Field("string", fend.String(u.String, rule.RequiredString)),
	)
	if err != nil {
		panic("internal error: " + err.Error())
	}
	fmt.Println(fendErr) // uint:min=1;uint64:min=1;float32:min=1.5;int:min=1;int8:min=1;uint8:min=1;uint32:min=1;float64:min=1.5;bool:bool=true;string:required;int32:min=1;int64:min=1
}

validate by code and stop on first error

package main

import (
	"fmt"

	"github.com/foomo/fender"
	"github.com/foomo/fender/fend"
	"github.com/foomo/fender/rule"
)

type Test struct {
	Int     int
	Int8    int8
	Int32   int32
	Int64   int64
	UInt    uint
	UInt8   uint8
	UInt32  uint32
	UInt64  uint64
	Float32 float32
	Float64 float64
	Bool    bool
	String  string
}

func main() {
	u := Test{}
	fendErr, err := fender.First(
		fender.Field("int", fend.Int(u.Int, rule.MinInt(1))),
		fender.Field("int8", fend.Int8(u.Int8, rule.MinInt8(1))),
		fender.Field("int32", fend.Int32(u.Int32, rule.MinInt32(1))),
		fender.Field("int64", fend.Int64(u.Int64, rule.MinInt64(1))),
		fender.Field("uint", fend.UInt(u.UInt, rule.MinUInt(1))),
		fender.Field("uint8", fend.UInt8(u.UInt8, rule.MinUInt8(1))),
		fender.Field("uint32", fend.UInt32(u.UInt32, rule.MinUInt32(1))),
		fender.Field("uint64", fend.UInt64(u.UInt64, rule.MinUInt64(1))),
		fender.Field("float32", fend.Float32(u.Float32, rule.MinFloat32(1.5))),
		fender.Field("float64", fend.Float64(u.Float64, rule.MinFloat64(1.5))),
		fender.Field("bool", fend.Bool(u.Bool, rule.Bool(true))),
		fender.Field("string", fend.String(u.String, rule.RequiredString)),
	)
	if err != nil {
		panic("internal error: " + err.Error())
	}
	fmt.Println(fendErr) // int:min=1
}

References & alternatives

• go-playground/validator
• go-ozzo/ozzo-validation

How to Contribute

Make a pull request...

License

Distributed under MIT License, please see license file within the code for more details.

Notes

We'll take another refactoring round as soon as go supports generics

Documentation

Index

• Variables
• func NewWrappedError(err error, cause *Error) error
• func WrapError(err error, cause *Error) error
• type Error
  • func All(fields ...FendField) (*Error, error)
  • func First(fields ...FendField) (*Error, error)
  • func NewError(fields FieldErrors) *Error
  • func Struct(s interface{}) (*Error, error)
  • func UnwrapError(err error) *Error
  • func (e *Error) Error() string
  • func (e *Error) Errors() FieldErrors
  • func (e *Error) First() error
  • func (e *Error) Is(err error) bool
• type FendField
  • func Field(name string, fends ...fend.Fend) FendField
• type FendFields
  • func (f FendFields) Add(fields ...FendField) FendFields
• type FieldErrors
  • func (m FieldErrors) String() string

Variables

var Err = &Error{}

Functions

func NewWrappedError

func NewWrappedError(err error, cause *Error) error

func WrapError

func WrapError(err error, cause *Error) error

Types

type Error

type Error struct {
	Fields FieldErrors
}

Error type

func All

func All(fields ...FendField) (*Error, error)

func First

func First(fields ...FendField) (*Error, error)

func NewError

func NewError(fields FieldErrors) *Error

NewError constructor

func Struct

func Struct(s interface{}) (*Error, error)

func UnwrapError

func UnwrapError(err error) *Error

func (*Error) Error

func (e *Error) Error() string

Error interface

func (*Error) Errors

func (e *Error) Errors() FieldErrors

func (*Error) First

func (e *Error) First() error

func (*Error) Is

func (e *Error) Is(err error) bool

Is interface

type FendField

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

func Field

func Field(name string, fends ...fend.Fend) FendField

type FendFields

type FendFields []FendField

func (FendFields) Add

func (f FendFields) Add(fields ...FendField) FendFields

type FieldErrors

type FieldErrors map[string]*rule.Error

FieldErrors type

func (FieldErrors) String

func (m FieldErrors) String() string

String returns the string representation