Validate a phone number.

This validator uses libphonenumber under the hood to validate phone numbers.

This validator expects a :country argument to be passed so it can check the number corresponds to the given country.

If you pass it "" or nil it won't complain as long as the number is a valid E164 format that can be parsed without the country info.

Examples

iex> types = %{phone_number: :string}
iex> params = %{phone_number: "0610234567"}
iex> Ecto.Changeset.cast({%{}, types}, params, Map.keys(types))
...> |> validate_phone_number(:phone_number, country: "fr")
#Ecto.Changeset<action: nil, changes: %{phone_number: "0610234567"}, errors: [], data: %{}, valid?: true>

iex> types = %{phone_number: :string}
iex> params = %{phone_number: "798765432L"}
iex> Ecto.Changeset.cast({%{}, types}, params, Map.keys(types))
...> |> validate_phone_number(:phone_number, country: "ch")
#Ecto.Changeset<action: nil, changes: %{phone_number: "798765432L"}, errors: [], data: %{}, valid?: true>

# Country can be ignored in E164 formatted numbers
iex> types = %{phone_number: :string}
iex> params = %{phone_number: "+16502530000"}
iex> Ecto.Changeset.cast({%{}, types}, params, Map.keys(types))
...> |> validate_phone_number(:phone_number)
#Ecto.Changeset<action: nil, changes: %{phone_number: "+16502530000"}, errors: [], data: %{}, valid?: true>

iex> types = %{phone_number: :string}
iex> params = %{phone_number: "01 23 45 67 89"}
iex> Ecto.Changeset.cast({%{}, types}, params, Map.keys(types))
...> |> validate_phone_number(:phone_number, country: nil)
#Ecto.Changeset<action: nil, changes: %{phone_number: "01 23 45 67 89"}, errors: [phone_number: {"is not a valid phone number", [validation: :phone_number]}], data: %{}, valid?: false>