validate

Validate functions generator

Basic model required, which can be generated with one of the model generators

Use validate sub-command to execute generator:

genna validate -h

First create your database and tables in it

create table "projects"
(
    "projectId" serial not null,
    "name"      text   not null,

    primary key ("projectId")
);

create table "users"
(
    "userId"    serial      not null,
    "email"     varchar(64) not null,
    "activated" bool        not null default false,
    "name"      varchar(128),
    "countryId" integer,

    primary key ("userId")
);

create schema "geo";
create table geo."countries"
(
    "countryId" serial     not null,
    "code"      varchar(3) not null,
    "coords"    integer[],

    primary key ("countryId")
);

alter table "users"
    add constraint "fk_user_country"
        foreign key ("countryId")
            references geo."countries" ("countryId") on update restrict on delete restrict;

Run generator

genna validate -c postgres://user:password@localhost:5432/yourdb -o ~/output/model.go -t public.* -f

You should get following functions on model package:

//lint:file-ignore U1000 ignore unused code, it's generated
package model

import (
	"unicode/utf8"
)

const (
	ErrEmptyValue = "empty"
	ErrMaxLength  = "len"
	ErrWrongValue = "value"
)

func (m User) Validate() (errors map[string]string, valid bool) {
	errors = map[string]string{}

	if utf8.RuneCountInString(m.Email) > 64 {
		errors[Columns.User.Email] = ErrMaxLength
	}

	if m.Name != nil && utf8.RuneCountInString(*m.Name) > 128 {
		errors[Columns.User.Name] = ErrMaxLength
	}

	if m.CountryID != nil && *m.CountryID == 0 {
		errors[Columns.User.CountryID] = ErrEmptyValue
	}

	return errors, len(errors) == 0
}

func (m GeoCountry) Validate() (errors map[string]string, valid bool) {
	errors = map[string]string{}

	if utf8.RuneCountInString(m.Code) > 3 {
		errors[Columns.GeoCountry.Code] = ErrMaxLength
	}

	return errors, len(errors) == 0
}

Try it

package model

import (
	"fmt"
	"testing"
)

func TestModel(t *testing.T) {
    code := "should fail on length"
    country := GeoCountry{
    	Code: code,
    }
    errors, valid := country.Validate()

	fmt.Printf("%#v\n", errors)
	fmt.Printf("%#v\n", valid)
}