Kurisu
How to validate that a decimal number is an integer in an Ecto changeset?
I’m using the Decimal package to work with a field in my changeset.
field :amount, :decimal
I can validate it with validate_number so that it should be greater or equal to a given number.
But for now I would like the user to submit an integer for this field (:amount).
I do not want to change the Ecto type to :integer but just want to have a decimal number with zero as decimal part.
Please any suggestion on how to achieve this with a custom Ecto validator, given that the field is of type :decimal?
Marked As Solved
Aetherus
Maybe you can check if it equals to the rounded version of itself.
defp validate_integer(changeset, field) do
if integer?(get_field(changeset, field)) do
changeset
else
add_error(changeset, field, "An integer is expected.")
end
end
defp integer?(decimal) do
decimal
|> Decimal.round()
|> Decimal.equal?(decimal)
end
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Kurisu
Aetherus
My pleasure.
I was assuming that the field should not be nil and is validated with Ecto.Changeset.validate_required before piping into this validate_integer. My fault.
al2o3cr
FWIW, Ecto.Changeset.validate_change would give you the "don’t bother doing this if the value is nil" behavior as well.
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