Iris, wisely, not features a builtin data validation. However, it does allow you to attach a validator which will automatically called on methods like Context.ReadJSON, ReadXML...
. In this example we will learn how to use the go-playground/validator/v10 for request body validation.
Check the full docs and the struct tags usage here.
$ go get github.com/go-playground/validator/v10@latest
Note that you need to set the corresponding binding tag on all fields you want to bind. For example, when binding from JSON, set json:"fieldname"
.
package mainimport ("fmt""github.com/kataras/iris/v12""github.com/go-playground/validator/v10")// User contains user information.type User struct {FirstName string `json:"fname"`LastName string `json:"lname"`Age uint8 `json:"age" validate:"gte=0,lte=130"`Email string `json:"email" validate:"required,email"`FavouriteColor string `json:"favColor" validate:"hexcolor|rgb|rgba"`Addresses []*Address `json:"addresses" validate:"required,dive,required"`}// Address houses a users address information.type Address struct {Street string `json:"street" validate:"required"`City string `json:"city" validate:"required"`Planet string `json:"planet" validate:"required"`Phone string `json:"phone" validate:"required"`}func main() {// Use a single instance of Validate, it caches struct info.v := validator.New()// Register a custom struct validation for 'User'// NOTE: only have to register a non-pointer type for 'User', validator// internally dereferences during it's type checks.v.RegisterStructValidation(UserStructLevelValidation, User{})app := iris.New()// Register the validator to the Iris Application.app.Validator = vapp.Post("/user", func(ctx iris.Context) {var user User// Returns InvalidValidationError for bad validation input,// nil or ValidationErrors ( []FieldError )err := ctx.ReadJSON(&user)if err != nil {// This check is only needed when your code could produce// an invalid value for validation such as interface with nil// value most including myself do not usually have code like this.if _, ok := err.(*validator.InvalidValidationError); ok {ctx.StatusCode(iris.StatusInternalServerError)ctx.WriteString(err.Error())return}ctx.StatusCode(iris.StatusBadRequest)for _, err := range err.(validator.ValidationErrors) {fmt.Println()fmt.Println(err.Namespace())fmt.Println(err.Field())fmt.Println(err.StructNamespace())fmt.Println(err.StructField())fmt.Println(err.Tag())fmt.Println(err.ActualTag())fmt.Println(err.Kind())fmt.Println(err.Type())fmt.Println(err.Value())fmt.Println(err.Param())fmt.Println()}return}// [save user to database...]})app.Listen(":8080")}func UserStructLevelValidation(sl validator.StructLevel) {user := sl.Current().Interface().(User)if len(user.FirstName) == 0 && len(user.LastName) == 0 {sl.ReportError(user.FirstName, "FirstName", "fname", "fnameorlname", "")sl.ReportError(user.LastName, "LastName", "lname", "fnameorlname", "")}}
Example request of JSON form:
{"fname": "","lname": "","age": 45,"email": "mail@example.com","favColor": "#000","addresses": [{"street": "Eavesdown Docks","planet": "Persphone","phone": "none","city": "Unknown"}]}
Example can be found at: https://github.com/kataras/iris/tree/master/_examples/request-body/read-json-struct-validation/main.go.