package main import ( "fmt" "github.com/go-playground/validator/v10" ) var validate *validator.Validate func main() { validate = validator.New() validateMap() validateNestedMap() } func validateMap() { user := map[string]interface{}{"name": "Arshiya Kiani", "email": "zytel3301@gmail.com"} // Every rule will be applied to the item of the data that the offset of rule is pointing to. // So if you have a field "email": "omitempty,required,email", the validator will apply these // rules to offset of email in user data rules := map[string]interface{}{"name": "required,min=8,max=32", "email": "omitempty,required,email"} // ValidateMap will return map[string]error. // The offset of every item in errs is the name of invalid field and the value // is the message of error. If there was no error, ValidateMap method will // return an EMPTY map of errors, not nil. If you want to check that // if there was an error or not, you must check the length of the return value errs := validate.ValidateMap(user, rules) if len(errs) > 0 { fmt.Println(errs) // The user is invalid } // The user is valid } func validateNestedMap() { data := map[string]interface{}{ "name": "Arshiya Kiani", "email": "zytel3301@gmail.com", "details": map[string]interface{}{ "family_members": map[string]interface{}{ "father_name": "Micheal", "mother_name": "Hannah", }, "salary": "1000", "phones": []map[string]interface{}{ { "number": "11-111-1111", "remark": "home", }, { "number": "22-222-2222", "remark": "work", }, }, }, } // Rules must be set as the structure as the data itself. If you want to dive into the // map, just declare its rules as a map rules := map[string]interface{}{ "name": "min=4,max=32", "email": "required,email", "details": map[string]interface{}{ "family_members": map[string]interface{}{ "father_name": "required,min=4,max=32", "mother_name": "required,min=4,max=32", }, "salary": "number", "phones": map[string]interface{}{ "number": "required,min=4,max=32", "remark": "required,min=1,max=32", }, }, } if len(validate.ValidateMap(data, rules)) == 0 { // Data is valid } // Data is invalid }