defmodule Pow.Ecto.Schema do
@moduledoc """
Handles the Ecto schema for user.
The macro will create a `@pow_fields` module attribute, and append fields to
it using the attributes from `Pow.Ecto.Schema.Fields.attrs/1`. Likewise, a
`@pow_assocs` module attribute is also generated for associations. The
`pow_user_fields/0` macro will use these attributes to create fields and
associations in the ecto schema.
The macro will add two overridable methods to your module; `changeset/2`
and `verify_password/2`. See the customization section below for more.
The following helper methods are added for changeset customization:
- `pow_changeset/2`,
- `pow_verify_password/2`
- `pow_user_id_field_changeset/2`
- `pow_password_changeset/2`,
- `pow_current_password_changeset/2`,
Finally `pow_user_id_field/0` method is added to the module that is used to
fetch the user id field name.
A `@pow_config` module attribute is created containing the options that were
passed to the macro with the `use Pow.Ecto.Schema, ...` call.
See `Pow.Ecto.Schema.Changeset` for more.
## Usage
Configure `lib/my_project/users/user.ex` the following way:
defmodule MyApp.Users.User do
use Ecto.Schema
use Pow.Ecto.Schema,
user_id_field: :email,
password_hash_methods: {&Pow.Ecto.Schema.Password.pbkdf2_hash/1,
&Pow.Ecto.Schema.Password.pbkdf2_verify/2},
password_min_length: 8,
password_max_length: 4096
schema "users" do
field :custom_field, :string
pow_user_fields()
timestamps()
end
def changeset(user_or_changeset, attrs) do
pow_changeset(user_or_changeset, attrs)
end
end
Remember to add `user: MyApp.Users.User` to your configuration.
## Configuration options
* `:user_id_field` - the field to use for user id. This value defaults to
`:email`, and the changeset will automatically validate it as an e-mail.
## Customize Pow fields
Pow fields can be overridden if the field name and type matches:
defmodule MyApp.Users.User do
use Ecto.Schema
use Pow.Ecto.Schema
schema "users" do
field :encrypted_password, :string
field :password_hash, :string, source: :encrypted_password
pow_user_fields()
timestamps()
end
end
The same holds true for associations:
defmodule MyApp.Users.User do
use Ecto.Schema
use Pow.Ecto.Schema
@pow_assocs {:belongs_to, :invited_by, __MODULE__, []}
@pow_assocs {:has_many, :invited, __MODULE__, []}
schema "users" do
belongs_to :invited_by, __MODULE__, foreign_key: :user_id
pow_user_fields()
timestamps()
end
end
An `@after_compile` callback will emit IO warning if there are missing fields
or associations. You can forego the `pow_user_fields/0` call, and write out
the whole schema instead:
defmodule MyApp.Users.User do
use Ecto.Schema
use Pow.Ecto.Schema, user_id_field: :email
schema "users" do
field :email, :string
field :password_hash, :string
field :current_password, :string, virtual: true
field :password, :string, virtual: true
field :confirm_password, :string, virtual: true
timestamps()
end
end
If you would like these warnings to be raised during compilation you can add
`elixirc_options: [warnings_as_errors: true]` to the project options in
`mix.exs`.
The warning is also emitted if the field has an invalid primitive Ecto type.
It'll not be emitted for custom Ecto types.
## Customize Pow changeset
You can extract individual changeset methods to modify the changeset flow
entirely. As an example, this is how you can remove the validation check for
confirm password in the changeset method:
defmodule MyApp.Users.User do
use Ecto.Schema
use Pow.Ecto.Schema
import Pow.Ecto.Schema.Changeset, only: [new_password_changeset: 3]
# ...
def changeset(user_or_changeset, attrs) do
user_or_changeset
|> pow_user_id_field_changeset(attrs)
|> pow_current_password_changeset(attrs)
|> new_password_changeset(attrs, @pow_config)
end
end
Note that the changeset methods in `Pow.Ecto.Schema.Changeset` require the
Pow ecto module configuration that is passed to the
`use Pow.Ecto.Schema, ...` call. This can be fetched by using the
`@pow_config` module attribute.
"""
alias Ecto.{Changeset, Type}
alias Pow.Config
defmodule SchemaError do
@moduledoc false
defexception [:message]
end
@callback changeset(Ecto.Schema.t() | Changeset.t(), map()) :: Changeset.t()
@callback verify_password(Ecto.Schema.t(), binary()) :: boolean()
@doc false
defmacro __using__(config) do
quote do
@behaviour unquote(__MODULE__)
@pow_config unquote(config)
def changeset(user_or_changeset, attrs), do: pow_changeset(user_or_changeset, attrs)
def verify_password(user, password), do: pow_verify_password(user, password)
defoverridable unquote(__MODULE__)
unquote(__MODULE__).__pow_methods__()
unquote(__MODULE__).__register_fields__()
unquote(__MODULE__).__register_assocs__()
unquote(__MODULE__).__register_user_id_field__()
unquote(__MODULE__).__register_after_compile_validation__()
end
end
@changeset_methods [:user_id_field_changeset, :password_changeset, :current_password_changeset]
@doc false
defmacro __pow_methods__ do
quoted_changeset_methods =
for method <- @changeset_methods do
pow_method_name = String.to_atom("pow_#{method}")
quote do
def unquote(pow_method_name)(user_or_changeset, attrs) do
unquote(__MODULE__).Changeset.unquote(method)(user_or_changeset, attrs, @pow_config)
end
end
end
quote do
import unquote(__MODULE__), only: [pow_user_fields: 0]
def pow_changeset(user_or_changeset, attrs) do
user_or_changeset
|> pow_user_id_field_changeset(attrs)
|> pow_current_password_changeset(attrs)
|> pow_password_changeset(attrs)
end
unquote(quoted_changeset_methods)
def pow_verify_password(user, password) do
unquote(__MODULE__).Changeset.verify_password(user, password, @pow_config)
end
end
end
@doc """
A macro to add fields from the `@pow_fields` module attribute generated in
`__using__/1`.
The `@pow_fields` are populated by `Pow.Ecto.Schema.Fields.attrs/1`, and will
have at minimum the following fields:
* `:email` (if not changed with `:user_id_field` option)
* `:password_hash`
* `:current_password` (virtual)
* `:password` (virtual)
"""
defmacro pow_user_fields do
quote do
unquote(__MODULE__).__append_assocs__(@pow_assocs, @ecto_assocs)
unquote(__MODULE__).__append_fields__(@pow_fields, @ecto_fields)
end
end
defmacro __append_assocs__(assocs, ecto_assocs) do
quote do
unquote(assocs)
|> unquote(__MODULE__).__filter_new_assocs__(unquote(ecto_assocs))
|> Enum.each(fn
{:belongs_to, name, queryable, options} ->
belongs_to(name, queryable, options)
{:has_many, name, queryable, options} ->
has_many(name, queryable, options)
end)
end
end
@doc false
def __filter_new_assocs__(assocs, existing_assocs) do
Enum.reject(assocs, fn assoc ->
Enum.any?(existing_assocs, &assocs_match?(elem(assoc, 0), elem(assoc, 1), &1))
end)
end
defp assocs_match?(:has_many, name, {name, %Ecto.Association.Has{cardinality: :many}}), do: true
defp assocs_match?(:belongs_to, name, {name, %Ecto.Association.BelongsTo{}}), do: true
defp assocs_match?(_type, _name, _existing_assoc), do: false
defmacro __append_fields__(fields, ecto_fields) do
quote do
unquote(fields)
|> unquote(__MODULE__).__filter_new_fields__(unquote(ecto_fields))
|> Enum.each(fn
{name, type} ->
field(name, type)
{name, type, defaults} ->
field(name, type, defaults)
end)
end
end
@doc false
def __filter_new_fields__(fields, existing_fields) do
Enum.filter(fields, ¬ Enum.member?(existing_fields, {elem(&1, 0), elem(&1, 1)}))
end
# TODO: Remove by 1.1.0
@deprecated "No longer public method"
def filter_new_fields(fields, existing_fields), do: __filter_new_fields__(fields, existing_fields)
@doc false
defmacro __register_fields__ do
quote do
Module.register_attribute(__MODULE__, :pow_fields, accumulate: true)
@pow_config
|> unquote(__MODULE__).Fields.attrs()
|> Enum.each(fn {name, value, field_options, _migration_options} ->
Module.put_attribute(__MODULE__, :pow_fields, {name, value, field_options})
end)
end
end
@doc false
defmacro __register_assocs__ do
quote do
Module.register_attribute(__MODULE__, :pow_assocs, accumulate: true)
end
end
@doc false
defmacro __register_user_id_field__ do
quote do
@user_id_field unquote(__MODULE__).user_id_field(@pow_config)
def pow_user_id_field, do: @user_id_field
end
end
@doc """
Get user id field key from changeset or configuration.
Defaults to `:email`.
"""
@default_user_id_field :email
@spec user_id_field(Changeset.t() | Config.t()) :: atom()
def user_id_field(%Changeset{data: %user_mod{}}), do: user_mod.pow_user_id_field()
def user_id_field(config) when is_list(config), do: Config.get(config, :user_id_field, @default_user_id_field)
def user_id_field(_any), do: @default_user_id_field
@doc false
defmacro __register_after_compile_validation__ do
quote do
def pow_validate_after_compilation!(env, _bytecode) do
unquote(__MODULE__).__require_assocs__(__MODULE__)
unquote(__MODULE__).__require_fields__(__MODULE__)
end
@after_compile {__MODULE__, :pow_validate_after_compilation!}
end
end
@doc false
def __require_assocs__(module) do
ecto_assocs = Module.get_attribute(module, :ecto_assocs)
module
|> Module.get_attribute(:pow_assocs)
|> Enum.map(&validate_assoc!/1)
|> Enum.reverse()
|> Enum.filter(fn {type, name, _queryable, _defaults} ->
not Enum.any?(ecto_assocs, &assocs_match?(type, name, &1))
end)
|> Enum.map(fn
{type, name, queryable, []} -> "#{type} #{inspect name}, #{inspect queryable}"
{type, name, queryable, defaults} -> "#{type} #{inspect name}, #{inspect queryable}, #{inspect defaults}"
end)
|> case do
[] -> :ok
assoc_defs -> warn_missing_assocs_error(module, assoc_defs)
end
end
defp validate_assoc!({_type, _name, _module, _defaults} = assoc), do: assoc
defp validate_assoc!(value) do
raise """
`@pow_assocs` is required to have the format `{type, field, module, defaults}`.
The value provided was: #{inspect value}
"""
end
defp warn_missing_assocs_error(module, assoc_defs) do
IO.warn(
"""
Please define the following association(s) in the schema for #{inspect module}:
#{Enum.join(assoc_defs, "\n")}
""")
end
@doc false
def __require_fields__(module) do
ecto_fields = Module.get_attribute(module, :ecto_fields)
# TODO: Require Ecto 3.8.0 in 1.1.0 and remove `:changeset_fields`
changeset_fields = Module.get_attribute(module, :ecto_changeset_fields) || Module.get_attribute(module, :changeset_fields)
module
|> Module.get_attribute(:pow_fields)
|> Enum.map(&validate_field!/1)
|> Enum.reverse()
|> Enum.filter(&missing_field?(&1, ecto_fields, changeset_fields))
|> Enum.map(fn
{name, type, []} -> "field #{inspect name}, #{inspect type}"
{name, type, defaults} -> "field #{inspect name}, #{inspect type}, #{inspect defaults}"
end)
|> case do
[] -> :ok
field_defs -> warn_missing_fields_error(module, field_defs)
end
end
defp validate_field!({_name, _type, _defaults} = assoc), do: assoc
defp validate_field!(value) do
raise """
`@pow_fields` is required to have the format `{name, type, defaults}`.
The value provided was: #{inspect value}
"""
end
defp missing_field?({name, type, field_options}, ecto_fields, changeset_fields) do
case field_options[:virtual] do
true -> missing_field?(name, type, changeset_fields)
_any -> missing_field?(name, type, ecto_fields)
end
end
defp missing_field?(name, type, existing_fields) when is_atom(name) do
not Enum.any?(existing_fields, fn
{^name, ^type} -> true
{^name, e_type} -> not Type.primitive?(e_type)
_any -> false
end)
end
defp warn_missing_fields_error(module, field_defs) do
IO.warn(
"""
Please define the following field(s) in the schema for #{inspect module}:
#{Enum.join(field_defs, "\n")}
""")
end
@doc """
Normalizes the user id field.
Keeps the user id field value case insensitive and removes leading and
trailing whitespace.
"""
@spec normalize_user_id_field_value(binary()) :: binary()
def normalize_user_id_field_value(value) do
value
|> String.trim()
|> String.downcase()
end
@doc false
def __timestamp_for__(struct, column) do
type = struct.__schema__(:type, column)
__timestamp__(type)
end
@doc false
def __timestamp__(:naive_datetime) do
%{NaiveDateTime.utc_now() | microsecond: {0, 0}}
end
def __timestamp__(:naive_datetime_usec) do
NaiveDateTime.utc_now()
end
def __timestamp__(:utc_datetime) do
DateTime.from_unix!(System.system_time(:second), :second)
end
def __timestamp__(:utc_datetime_usec) do
DateTime.from_unix!(System.system_time(:microsecond), :microsecond)
end
def __timestamp__(type) do
type.from_unix!(System.system_time(:microsecond), :microsecond)
end
end
