Ecto.Validator.Predicates
A handful of predicates to be used in validations.
The examples in this module use the syntax made
available via Ecto.Model.Validations in your
model.
Summary↑
| absent(field, value, opts \\ []) | Validates the attribute is absent (i.e. nil, an empty list or an empty string) |
| between(field, value, arg3, opts \\ []) | Validates the given number is between the value. Expects a range as value, raises otherwise |
| greater_than(field, value, check, opts \\ []) | Validates the given number is greater than the given value. Expects numbers as value, raises otherwise |
| greater_than_or_equal_to(field, value, check, opts \\ []) | Validates the given number is greater than or equal to the given value. Expects numbers as value, raises otherwise |
| has_format(field, value, match_on, opts \\ []) | Validates the attribute has a given format. Nil values are not matched against (skipped) |
| has_length(field, value, match_on, opts \\ []) | Validates the attribute has a given length according to Unicode
(i.e. it uses |
| less_than(field, value, check, opts \\ []) | Validates the given number is less than the given value. Expects numbers as value, raises otherwise |
| less_than_or_equal_to(field, value, check, opts \\ []) | Validates the given number is less than or equal to the given value. Expects numbers as value, raises otherwise |
| member_of(field, value, enum, opts \\ []) | Validates the attribute is member of the given enumerable |
| not_member_of(field, value, enum, opts \\ []) | Validates the attribute is not a member of the given enumerable |
| present(field, value, opts \\ []) | Validates the attribute is present (i.e. not nil, nor an empty list nor an empty string) |
Types ↑
field :: atom
maybe_error :: nil | binary
Functions
Specs:
- absent(field, term, Keyword.t) :: maybe_error
Validates the attribute is absent (i.e. nil, an empty list or an empty string).
Options
:message- defaults to "must be blank"
Examples
validate user,
honeypot: absent()
Specs:
- between(field, number | nil, Range.t, Keyword.t) :: maybe_error
Validates the given number is between the value. Expects a range as value, raises otherwise.
Options
:message- defaults to "must be between X and Y"
Examples
validates user,
age: between(18..21)
Specs:
- greater_than(field, number | nil, number, Keyword.t) :: maybe_error
Validates the given number is greater than the given value. Expects numbers as value, raises otherwise.
Options
:message- defaults to "must be greater than X"
Examples
validates user,
age: greater_than(18)
Specs:
- greater_than_or_equal_to(field, number | nil, number, Keyword.t) :: maybe_error
Validates the given number is greater than or equal to the given value. Expects numbers as value, raises otherwise.
Options
:message- defaults to "must be greater than or equal to X"
Examples
validates user,
age: greater_than_or_equal_to(18)
Specs:
- has_format(field, term, Regex.t | binary, Keyword.t) :: maybe_error
Validates the attribute has a given format. Nil values are not matched against (skipped).
Options
:message- defaults to "is invalid"
Examples
validate user,
email: has_format(~r/@/)
Specs:
- has_length(field, term, Range.t | number, Keyword.t) :: maybe_error
Validates the attribute has a given length according to Unicode
(i.e. it uses String.length under the scenes). That said, this
function should not be used to validate binary fields.
The length can be given as a range (indicating min and max), as an integer (indicating exact match) or as keyword options, indicating, min and max values.
Raises if the given argument is not a binary.
Options
:too_long- message when the length is too long (defaults to "is too long (maximum is X characters)"):too_short- message when the length is too short (defaults to "is too short (minimum is X characters)"):no_match- message when the length does not match (defaults to "must be X characters")
Examples
validate user,
password: has_length(6..100)
validate user,
password: has_length(min: 6, too_short: "requires a minimum length")
validate user,
code: has_length(3, no_match: "needs to be 3 characters")
Specs:
- less_than(field, number | nil, number, Keyword.t) :: maybe_error
Validates the given number is less than the given value. Expects numbers as value, raises otherwise.
Options
:message- defaults to "must be less than X"
Examples
validates user,
age: less_than(18)
Specs:
- less_than_or_equal_to(field, number | nil, number, Keyword.t) :: maybe_error
Validates the given number is less than or equal to the given value. Expects numbers as value, raises otherwise.
Options
:message- defaults to "must be less than or equal to X"
Examples
validates user,
age: less_than_or_equal_to(18)
Specs:
- member_of(field, term, Enumerable.t, Keyword.t) :: maybe_error
Validates the attribute is member of the given enumerable.
This validator has the same semantics as calling Enum.member?/2
with the given enumerable and value.
Nil values are not matched against (skipped).
Options
:message- defaults to "is not included in the list"
Examples
validate user,
gender: member_of(~w(male female other))
validate user,
age: member_of(0..99)
Specs:
- not_member_of(field, term, Enumerable.t, Keyword.t) :: maybe_error
Validates the attribute is not a member of the given enumerable.
This validator has the same semantics as calling
not Enum.member?/2 with the given enumerable and value.
Nil values are not matched against (skipped).
Options
:message- defaults to "is reserved"
Examples
validate user,
username: not_member_of(~w(admin superuser))
validate user,
password: not_member_of([user.username, user.name],
message: "cannot be the same as username or first name")
Specs:
- present(field, term, Keyword.t) :: maybe_error
Validates the attribute is present (i.e. not nil, nor an empty list nor an empty string).
Options
:message- defaults to "can't be blank"
Examples
validate user,
name: present()