initial commit

lib/cannery/accounts/user.ex

@@ -0,0 +1,141 @@
+defmodule Cannery.Accounts.User do
+  use Ecto.Schema
+  import Ecto.Changeset
+
+  @derive {Inspect, except: [:password]}
+  @primary_key {:id, :binary_id, autogenerate: true}
+  @foreign_key_type :binary_id
+  schema "users" do
+    field :email, :string
+    field :password, :string, virtual: true
+    field :hashed_password, :string
+    field :confirmed_at, :naive_datetime
+
+    timestamps()
+  end
+
+  @doc """
+  A user changeset for registration.
+
+  It is important to validate the length of both email and password.
+  Otherwise databases may truncate the email without warnings, which
+  could lead to unpredictable or insecure behaviour. Long passwords may
+  also be very expensive to hash for certain algorithms.
+
+  ## Options
+
+    * `:hash_password` - Hashes the password so it can be stored securely
+      in the database and ensures the password field is cleared to prevent
+      leaks in the logs. If password hashing is not needed and clearing the
+      password field is not desired (like when using this changeset for
+      validations on a LiveView form), this option can be set to `false`.
+      Defaults to `true`.
+  """
+  def registration_changeset(user, attrs, opts \\ []) do
+    user
+    |> cast(attrs, [:email, :password])
+    |> validate_email()
+    |> validate_password(opts)
+  end
+
+  defp validate_email(changeset) do
+    changeset
+    |> validate_required([:email])
+    |> validate_format(:email, ~r/^[^\s]+@[^\s]+$/, message: "must have the @ sign and no spaces")
+    |> validate_length(:email, max: 160)
+    |> unsafe_validate_unique(:email, Cannery.Repo)
+    |> unique_constraint(:email)
+  end
+
+  defp validate_password(changeset, opts) do
+    changeset
+    |> validate_required([:password])
+    |> validate_length(:password, min: 12, max: 80)
+    # |> validate_format(:password, ~r/[a-z]/, message: "at least one lower case character")
+    # |> validate_format(:password, ~r/[A-Z]/, message: "at least one upper case character")
+    # |> validate_format(:password, ~r/[!?@#$%^&*_0-9]/, message: "at least one digit or punctuation character")
+    |> maybe_hash_password(opts)
+  end
+
+  defp maybe_hash_password(changeset, opts) do
+    hash_password? = Keyword.get(opts, :hash_password, true)
+    password = get_change(changeset, :password)
+
+    if hash_password? && password && changeset.valid? do
+      changeset
+      |> put_change(:hashed_password, Bcrypt.hash_pwd_salt(password))
+      |> delete_change(:password)
+    else
+      changeset
+    end
+  end
+
+  @doc """
+  A user changeset for changing the email.
+
+  It requires the email to change otherwise an error is added.
+  """
+  def email_changeset(user, attrs) do
+    user
+    |> cast(attrs, [:email])
+    |> validate_email()
+    |> case do
+      %{changes: %{email: _}} = changeset -> changeset
+      %{} = changeset -> add_error(changeset, :email, "did not change")
+    end
+  end
+
+  @doc """
+  A user changeset for changing the password.
+
+  ## Options
+
+    * `:hash_password` - Hashes the password so it can be stored securely
+      in the database and ensures the password field is cleared to prevent
+      leaks in the logs. If password hashing is not needed and clearing the
+      password field is not desired (like when using this changeset for
+      validations on a LiveView form), this option can be set to `false`.
+      Defaults to `true`.
+  """
+  def password_changeset(user, attrs, opts \\ []) do
+    user
+    |> cast(attrs, [:password])
+    |> validate_confirmation(:password, message: "does not match password")
+    |> validate_password(opts)
+  end
+
+  @doc """
+  Confirms the account by setting `confirmed_at`.
+  """
+  def confirm_changeset(user) do
+    now = NaiveDateTime.utc_now() |> NaiveDateTime.truncate(:second)
+    change(user, confirmed_at: now)
+  end
+
+  @doc """
+  Verifies the password.
+
+  If there is no user or the user doesn't have a password, we call
+  `Bcrypt.no_user_verify/0` to avoid timing attacks.
+  """
+  def valid_password?(%Cannery.Accounts.User{hashed_password: hashed_password}, password)
+      when is_binary(hashed_password) and byte_size(password) > 0 do
+    Bcrypt.verify_pass(password, hashed_password)
+  end
+
+  def valid_password?(_, _) do
+    Bcrypt.no_user_verify()
+    false
+  end
+
+  @doc """
+  Validates the current password otherwise adds an error to the changeset.
+  """
+  def validate_current_password(changeset, password) do
+    if valid_password?(changeset.data, password) do
+      changeset
+    else
+      add_error(changeset, :current_password, "is not valid")
+    end
+  end
+end