defmodule Address.AddressCtx.Address do
use Ecto.Schema
import Ecto.Changeset
schema "addresses" do
field :street1, :string, size: 250, default: ""
field :street2, :string, size: 250, default: ""
field :city, :string, size: 100, default: ""
field :state, :string, size: 2, default: ""
field :zip, :string, size: 32, default: ""
field :country, :string, size: 3, default: "US"
field :fingerprint, :string, size: 32, default: ""
timestamps()
end
@doc false
def changeset(address, attrs) do
address
|> cast(attrs, [:street1, :street2, :city, :state, :zip, :country, :fingerprint])
|> validate_required([:street1, :city, :state, :zip, :country])
|> append_fingerprint()
|> unique_constraint(:fingerprint, message: "Fingerprint already in use")
end
defp append_fingerprint(changeset) do
case changeset do
%Ecto.Changeset{valid?: true, changes: %{address: address}} ->
IO.puts(address)
put_change(changeset, :fingerprint, get_fingerprint(address))
_ ->
changeset
end
end
@doc """
Simple md5 fingerprint
"""
def get_fingerprint(address) do
address.street1 <> address.street2 <> address.city <> address.state <> address.zip <> address.country
|> String.upcase
|> :erlang.md5
|> Base.encode16(case: :lower)
end
end
Here’s my schema file – the get_fingerprint() function seems to work when I test it in iex, so I’m thinking I’ve missed something in the cast() or other functions inside changeset since I’m not fully understanding the pieces of that.
Are there times when you would want to define a field in the database but not list it in the fields passed to cast()?
