Check if a field value is already used

This class provides a stub validator for fields that should contain a unique value along an application (typically logins or ids).

Here an example that uses a Repository if an email is unique:

class UniqueEmailField
    super UniqueField

    var users: UsersRepository

    redef fun check_unicity(v, field, val) do
        var user = users.find_by_email(val)
        if user != null then
            v.validation.add_error(field, "Email `{val}` already used")
            return false
        end
        return true
    end
end

Introduced properties

abstract fun check_unicity(v: ObjectValidator, field: String, val: String): Bool

popcorn :: UniqueField :: check_unicity

Check if val is already used somewhere
init defaultinit(field: String, required: nullable Bool, min_size: nullable Int, max_size: nullable Int)

popcorn :: UniqueField :: defaultinit

Redefined properties

redef type SELF: UniqueField

popcorn $ UniqueField :: SELF

Type of this instance, automatically specialized in every class
redef fun validate_field(v: ObjectValidator, obj: JsonObject): Bool

popcorn $ UniqueField :: validate_field

Validate field in obj

All properties

fun !=(other: nullable Object): Bool

core :: Object :: !=

Have self and other different values?
fun ==(other: nullable Object): Bool

core :: Object :: ==

Have self and other the same value?
type CLASS: Class[SELF]

core :: Object :: CLASS

The type of the class of self.
type SELF: Object

core :: Object :: SELF

Type of this instance, automatically specialized in every class
abstract fun check_unicity(v: ObjectValidator, field: String, val: String): Bool

popcorn :: UniqueField :: check_unicity

Check if val is already used somewhere
protected fun class_factory(name: String): CLASS

core :: Object :: class_factory

Implementation used by get_class to create the specific class.
fun class_name: String

core :: Object :: class_name

The class name of the object.
init defaultinit(field: String, required: nullable Bool, min_size: nullable Int, max_size: nullable Int)

popcorn :: StringField :: defaultinit

init defaultinit(field: String, required: nullable Bool)

popcorn :: RequiredField :: defaultinit

init defaultinit(field: String, required: nullable Bool, min_size: nullable Int, max_size: nullable Int)

popcorn :: UniqueField :: defaultinit

fun field: String

popcorn :: FieldValidator :: field

Field to validate
protected fun field=(field: String)

popcorn :: FieldValidator :: field=

Field to validate
fun get_class: CLASS

core :: Object :: get_class

The meta-object representing the dynamic type of self.
fun hash: Int

core :: Object :: hash

The hash code of the object.
init init

core :: Object :: init

fun inspect: String

core :: Object :: inspect

Developer readable representation of self.
protected fun inspect_head: String

core :: Object :: inspect_head

Return "CLASSNAME:#OBJECTID".
intern fun is_same_instance(other: nullable Object): Bool

core :: Object :: is_same_instance

Return true if self and other are the same instance (i.e. same identity).
fun is_same_serialized(other: nullable Object): Bool

core :: Object :: is_same_serialized

Is self the same as other in a serialization context?
intern fun is_same_type(other: Object): Bool

core :: Object :: is_same_type

Return true if self and other have the same dynamic type.
fun max_size: nullable Int

popcorn :: StringField :: max_size

String max size (default: not checked)
protected fun max_size=(max_size: nullable Int)

popcorn :: StringField :: max_size=

String max size (default: not checked)
fun min_size: nullable Int

popcorn :: StringField :: min_size

String min size (default: not checked)
protected fun min_size=(min_size: nullable Int)

popcorn :: StringField :: min_size=

String min size (default: not checked)
intern fun object_id: Int

core :: Object :: object_id

An internal hash code for the object based on its identity.
fun output

core :: Object :: output

Display self on stdout (debug only).
intern fun output_class_name

core :: Object :: output_class_name

Display class name on stdout (debug only).
fun required: nullable Bool

popcorn :: RequiredField :: required

Is this field required?
protected fun required=(required: nullable Bool)

popcorn :: RequiredField :: required=

Is this field required?
fun serialization_hash: Int

core :: Object :: serialization_hash

Hash value use for serialization
intern fun sys: Sys

core :: Object :: sys

Return the global sys object, the only instance of the Sys class.
abstract fun to_jvalue(env: JniEnv): JValue

core :: Object :: to_jvalue

fun to_s: String

core :: Object :: to_s

User readable representation of self.
abstract fun validate_field(v: ObjectValidator, obj: JsonObject): Bool

popcorn :: FieldValidator :: validate_field

Validate field in obj
package_diagram popcorn::UniqueField UniqueField popcorn::StringField StringField popcorn::UniqueField->popcorn::StringField popcorn::RequiredField RequiredField popcorn::StringField->popcorn::RequiredField ...popcorn::RequiredField ... ...popcorn::RequiredField->popcorn::RequiredField

Ancestors

abstract class FieldValidator

popcorn :: FieldValidator

Something that can validate a JsonObject field
interface Object

core :: Object

The root of the class hierarchy.
class RequiredField

popcorn :: RequiredField

Check if a field exists

Parents

class StringField

popcorn :: StringField

Check if a field is a String

Class definitions

popcorn $ UniqueField
# Check if a field value is already used
#
# This class provides a stub validator for fields that should contain a unique value along an
# application (typically logins or ids).
#
# Here an example that uses a `Repository` if an email is unique:
# ~~~nitish
# class UniqueEmailField
#	super UniqueField
#
#	var users: UsersRepository
#
#	redef fun check_unicity(v, field, val) do
#		var user = users.find_by_email(val)
#		if user != null then
#			v.validation.add_error(field, "Email `{val}` already used")
#			return false
#		end
#		return true
#	end
# end
# ~~~
class UniqueField
	super StringField

	# Check if `val` is already used somewhere
	#
	# You must redefine this method to handle your own validation.
	fun check_unicity(v: ObjectValidator, field, val: String): Bool is abstract

	redef fun validate_field(v, obj) do
		if not super then return false
		var val = obj.get_or_null(field)
		if not val isa String then return false
		if not check_unicity(v, field, val) then return false
		return true
	end
end
lib/popcorn/pop_validation.nit:773,1--810,3