who_need_help/lib/who_need_help/accounts.ex

601 lines
17 KiB
Elixir

defmodule WhoNeedHelp.Accounts do
@moduledoc """
The Accounts context.
"""
import Ecto.Query, warn: false
alias WhoNeedHelp.Pagination
alias WhoNeedHelp.Repo
alias WhoNeedHelp.Accounts.{Scope, SocialIdentity, User, UserToken, UserNotifier}
## Database getters
@public_user_fields [:id, :display_name, :bio, :tip_url, :inserted_at]
@public_social_identity_fields [
:id,
:provider,
:profile_url,
:handle,
:verified_at,
:user_id,
:inserted_at
]
@doc """
Returns the deliberately small user projection used by public and
participant-facing views.
Authentication, account settings, and moderation queries must continue to
load the full schema explicitly. In particular, this projection never loads
email, password hashes, roles, or moderation notes.
"""
def public_user_query(options \\ []) do
query =
from user in User,
select: struct(user, ^@public_user_fields)
if Keyword.get(options, :social_identities, false) do
public_social_identity = public_social_identity_query()
preload(query, social_identities: ^public_social_identity)
else
query
end
end
def public_social_identity_query do
from identity in SocialIdentity,
select: struct(identity, ^@public_social_identity_fields)
end
@doc """
Gets a user by email.
## Examples
iex> get_user_by_email("foo@example.com")
%User{}
iex> get_user_by_email("unknown@example.com")
nil
"""
def get_user_by_email(email) when is_binary(email) do
Repo.get_by(User, email: String.trim(email))
end
@doc """
Gets a user by email and password.
## Examples
iex> get_user_by_email_and_password("foo@example.com", "correct_password")
%User{}
iex> get_user_by_email_and_password("foo@example.com", "invalid_password")
nil
"""
def get_user_by_email_and_password(email, password)
when is_binary(email) and is_binary(password) do
user = get_user_by_email(email)
if User.valid_password?(user, password) and user.moderation_status != :suspended,
do: user
end
@doc """
Gets a single user.
Raises `Ecto.NoResultsError` if the User does not exist.
## Examples
iex> get_user!(123)
%User{}
iex> get_user!(456)
** (Ecto.NoResultsError)
"""
def get_user!(id), do: Repo.get!(User, id)
def eligible_for_trust_actions?(%User{
confirmed_at: confirmed_at,
accepted_terms_at: accepted_terms_at,
moderation_status: :active
}) do
not is_nil(confirmed_at) and not is_nil(accepted_terms_at)
end
def eligible_for_trust_actions?(_user), do: false
def eligible_user_id?(user_id) do
Repo.exists?(
from user in User,
where:
user.id == ^user_id and user.moderation_status == :active and
not is_nil(user.confirmed_at) and not is_nil(user.accepted_terms_at)
)
end
def moderator?(%User{role: role}), do: role in [:moderator, :admin]
def moderator?(_user), do: false
def moderator_authorized?(%User{id: id, role: role})
when role in [:moderator, :admin],
do:
Repo.exists?(
from user in User,
where:
user.id == ^id and user.role in [:moderator, :admin] and
user.moderation_status == :active
)
def moderator_authorized?(_user), do: false
def admin?(%User{role: :admin}), do: true
def admin?(_user), do: false
def admin_authorized?(%User{id: id, role: :admin}),
do:
Repo.exists?(
from user in User,
where: user.id == ^id and user.role == :admin and user.moderation_status == :active
)
def admin_authorized?(_user), do: false
def list_users_for_moderation(%Scope{user: user}) do
paginate_users_for_moderation(%Scope{user: user}).entries
end
def paginate_users_for_moderation(%Scope{user: user}, options \\ []) do
if moderator_authorized?(user) do
limit = Pagination.limit(options)
cursor = Pagination.cursor(options)
User
|> before_moderation_user(cursor)
|> order_by([user], desc: user.inserted_at, desc: user.id)
|> limit(^(limit + 1))
|> Repo.all()
|> Pagination.page(limit, &{&1.inserted_at, &1.id})
else
%Pagination.Page{}
end
end
def moderate_user(%User{} = moderator, user_id, attrs) do
with {:ok, user_id} <- cast_id(user_id),
true <- moderator_authorized?(moderator) do
Repo.transact(fn ->
active_admins = lock_active_admins()
user = User |> where([user], user.id == ^user_id) |> lock("FOR UPDATE") |> Repo.one()
if user do
requested_status = attrs["moderation_status"] || attrs[:moderation_status]
cond do
user.id == moderator.id and
requested_status in [:restricted, :suspended, "restricted", "suspended"] ->
{:error, :cannot_restrict_self}
user.role == :admin and user.moderation_status == :active and
requested_status not in [:active, "active"] and length(active_admins) == 1 ->
{:error, :last_admin}
true ->
with {:ok, user} <- user |> User.moderation_changeset(attrs) |> Repo.update() do
session_tokens =
if user.moderation_status == :suspended do
tokens =
UserToken
|> where([token], token.user_id == ^user.id and token.context == "session")
|> select([token], token.token)
|> Repo.all()
Repo.delete_all(from token in UserToken, where: token.user_id == ^user.id)
tokens
else
[]
end
{:ok, %{user: user, expired_session_tokens: session_tokens}}
end
end
else
{:error, :not_found}
end
end)
else
false -> {:error, :forbidden}
{:error, :not_found} = error -> error
end
end
def change_user_role(%User{} = admin, user_id, attrs) do
with {:ok, user_id} <- cast_id(user_id),
true <- admin_authorized?(admin) do
Repo.transact(fn ->
active_admins = lock_active_admins()
user = User |> where([user], user.id == ^user_id) |> lock("FOR UPDATE") |> Repo.one()
if user do
requested_role = attrs["role"] || attrs[:role]
if user.role == :admin and user.moderation_status == :active and
requested_role not in [:admin, "admin"] and length(active_admins) == 1 do
{:error, :last_admin}
else
user |> User.role_changeset(attrs) |> Repo.update()
end
else
{:error, :not_found}
end
end)
else
false -> {:error, :forbidden}
{:error, :not_found} = error -> error
end
end
defp lock_active_admins do
User
|> where([user], user.role == :admin and user.moderation_status == :active)
|> order_by([user], asc: user.id)
|> lock("FOR UPDATE")
|> Repo.all()
end
## User registration
@doc """
Registers a user.
## Examples
iex> register_user(%{field: value})
{:ok, %User{}}
iex> register_user(%{field: bad_value})
{:error, %Ecto.Changeset{}}
"""
def register_user(attrs) do
%User{}
|> User.registration_changeset(attrs)
|> Repo.insert()
end
def change_user_registration(%User{} = user, attrs \\ %{}, opts \\ []) do
User.registration_changeset(user, attrs, opts)
end
def change_user_profile(%User{} = user, attrs \\ %{}) do
User.profile_changeset(user, attrs)
end
def update_user_profile(%User{} = user, attrs) do
user
|> User.profile_changeset(attrs)
|> Repo.update()
end
def list_social_identities(%User{id: user_id}) do
SocialIdentity
|> where([identity], identity.user_id == ^user_id)
|> order_by([identity], asc: identity.provider, asc: identity.inserted_at)
|> Repo.all()
end
def change_social_identity(%SocialIdentity{} = identity, attrs \\ %{}) do
SocialIdentity.changeset(identity, attrs)
end
def add_social_identity(%User{id: user_id}, attrs) do
%SocialIdentity{user_id: user_id}
|> SocialIdentity.changeset(attrs)
|> Repo.insert()
end
def upsert_verified_social_identity(
%User{id: user_id},
%{provider: provider, provider_uid: provider_uid} = attrs
) do
Repo.transact(fn ->
existing =
SocialIdentity
|> where(
[identity],
identity.provider == ^provider and identity.provider_uid == ^provider_uid
)
|> lock("FOR UPDATE")
|> Repo.one()
case existing do
%SocialIdentity{user_id: ^user_id} = identity ->
identity
|> SocialIdentity.verified_changeset(Map.put(attrs, :user_id, user_id))
|> Repo.update()
%SocialIdentity{} ->
{:error, :already_linked}
nil ->
%SocialIdentity{}
|> SocialIdentity.verified_changeset(Map.put(attrs, :user_id, user_id))
|> Repo.insert()
end
end)
end
def delete_social_identity(%User{id: user_id}, identity_id) do
with {:ok, identity_id} <- Ecto.UUID.cast(identity_id),
%SocialIdentity{} = identity <-
Repo.get_by(SocialIdentity, id: identity_id, user_id: user_id) do
Repo.delete(identity)
else
_invalid_or_missing -> {:error, :not_found}
end
end
## Settings
@doc """
Checks whether the user is in sudo mode.
The user is in sudo mode when the last authentication was done no further
than 20 minutes ago. The limit can be given as second argument in minutes.
"""
def sudo_mode?(user, minutes \\ -20)
def sudo_mode?(%User{authenticated_at: ts}, minutes) when is_struct(ts, DateTime) do
DateTime.after?(ts, DateTime.utc_now() |> DateTime.add(minutes, :minute))
end
def sudo_mode?(_user, _minutes), do: false
@doc """
Returns an `%Ecto.Changeset{}` for changing the user email.
See `WhoNeedHelp.Accounts.User.email_changeset/3` for a list of supported options.
## Examples
iex> change_user_email(user)
%Ecto.Changeset{data: %User{}}
"""
def change_user_email(user, attrs \\ %{}, opts \\ []) do
User.email_changeset(user, attrs, opts)
end
@doc """
Updates the user email using the given token.
If the token matches, the user email is updated and the token is deleted.
"""
def update_user_email(user, token) do
context = "change:#{user.email}"
Repo.transact(fn ->
with {:ok, query} <- UserToken.verify_change_email_token_query(token, context),
%UserToken{sent_to: email} <- query |> lock("FOR UPDATE") |> Repo.one(),
{:ok, user} <- Repo.update(User.email_changeset(user, %{email: email})),
{count, _result} when count > 0 <-
Repo.delete_all(from(UserToken, where: [user_id: ^user.id, context: ^context])) do
{:ok, user}
else
_ -> {:error, :transaction_aborted}
end
end)
end
@doc """
Returns an `%Ecto.Changeset{}` for changing the user password.
See `WhoNeedHelp.Accounts.User.password_changeset/3` for a list of supported options.
## Examples
iex> change_user_password(user)
%Ecto.Changeset{data: %User{}}
"""
def change_user_password(user, attrs \\ %{}, opts \\ []) do
User.password_changeset(user, attrs, opts)
end
@doc """
Updates the user password.
Returns a tuple with the updated user, as well as a list of expired tokens.
## Examples
iex> update_user_password(user, %{password: ...})
{:ok, {%User{}, [...]}}
iex> update_user_password(user, %{password: "too short"})
{:error, %Ecto.Changeset{}}
"""
def update_user_password(user, attrs) do
user
|> User.password_changeset(attrs)
|> update_user_and_delete_all_tokens()
end
## Session
@doc """
Generates a session token.
"""
def generate_user_session_token(user) do
{token, user_token} = UserToken.build_session_token(user)
Repo.insert!(user_token)
token
end
@doc """
Gets the user with the given signed token.
If the token is valid `{user, token_inserted_at}` is returned, otherwise `nil` is returned.
"""
def get_user_by_session_token(token) do
{:ok, query} = UserToken.verify_session_token_query(token)
Repo.one(query)
end
@doc """
Gets the user with the given magic link token.
"""
def get_user_by_magic_link_token(token) do
with {:ok, query} <- UserToken.verify_magic_link_token_query(token),
{%User{moderation_status: status} = user, _token} <- Repo.one(query),
true <- status != :suspended do
user
else
_ -> nil
end
end
@doc """
Logs the user in by magic link.
There are three cases to consider:
1. The user has already confirmed their email. They are logged in
and the magic link is expired.
2. The user has not confirmed their email and no password is set.
In this case, the user gets confirmed, logged in, and all tokens -
including session ones - are expired. In theory, no other tokens
exist but we delete all of them for best security practices.
3. The user has not confirmed their email but a password is set.
This cannot happen in the default implementation but may be the
source of security pitfalls. See the "Mixing magic link and password registration" section of
`mix help phx.gen.auth`.
"""
def login_user_by_magic_link(token) do
with {:ok, query} <- UserToken.verify_magic_link_token_query(token) do
result =
Repo.transact(fn ->
case query |> lock("FOR UPDATE") |> Repo.one() do
{%User{moderation_status: :suspended}, token} ->
with {:ok, _token} <- Repo.delete(token) do
{:ok, {:rejected, :not_found}}
end
# Prevent session fixation attacks by disallowing magic links for unconfirmed users with password
{%User{confirmed_at: nil, hashed_password: hash}, _token} when not is_nil(hash) ->
raise """
magic link log in is not allowed for unconfirmed users with a password set!
This cannot happen with the default implementation, which indicates that you
might have adapted the code to a different use case. Please make sure to read the
"Mixing magic link and password registration" section of `mix help phx.gen.auth`.
"""
{%User{confirmed_at: nil} = user, _token} ->
user
|> User.confirm_changeset()
|> update_user_and_delete_all_tokens_in_transaction()
{user, token} ->
with {:ok, _token} <- Repo.delete(token) do
{:ok, {user, []}}
end
nil ->
{:error, :not_found}
end
end)
case result do
{:ok, {:rejected, reason}} -> {:error, reason}
other -> other
end
else
_invalid_token -> {:error, :not_found}
end
end
@doc ~S"""
Delivers the update email instructions to the given user.
## Examples
iex> deliver_user_update_email_instructions(user, current_email, &"https://example.test/users/settings/confirm-email#token=#{&1}")
{:ok, %{to: ..., body: ...}}
"""
def deliver_user_update_email_instructions(%User{} = user, current_email, update_email_url_fun)
when is_function(update_email_url_fun, 1) do
{encoded_token, user_token} = UserToken.build_email_token(user, "change:#{current_email}")
Repo.insert!(user_token)
UserNotifier.deliver_update_email_instructions(user, update_email_url_fun.(encoded_token))
end
@doc """
Delivers the magic link login instructions to the given user.
"""
def deliver_login_instructions(%User{} = user, magic_link_url_fun)
when is_function(magic_link_url_fun, 1) do
{encoded_token, user_token} = UserToken.build_email_token(user, "login")
Repo.insert!(user_token)
UserNotifier.deliver_login_instructions(user, magic_link_url_fun.(encoded_token))
end
@doc """
Deletes the signed token with the given context.
"""
def delete_user_session_token(token) do
Repo.delete_all(from(UserToken, where: [token: ^token, context: "session"]))
:ok
end
def delete_expired_user_tokens(now \\ DateTime.utc_now(:second)) do
now
|> UserToken.expired_tokens_query()
|> Repo.delete_all()
end
## Token helper
defp before_moderation_user(query, nil), do: query
defp before_moderation_user(query, {inserted_at, id}) do
where(
query,
[user],
user.inserted_at < ^inserted_at or
(user.inserted_at == ^inserted_at and user.id < ^id)
)
end
defp cast_id(value) do
case Ecto.UUID.cast(value) do
{:ok, id} -> {:ok, id}
:error -> {:error, :not_found}
end
end
defp update_user_and_delete_all_tokens(changeset) do
Repo.transact(fn -> update_user_and_delete_all_tokens_in_transaction(changeset) end)
end
defp update_user_and_delete_all_tokens_in_transaction(changeset) do
with {:ok, user} <- Repo.update(changeset) do
tokens_to_expire = Repo.all_by(UserToken, user_id: user.id)
Repo.delete_all(from(t in UserToken, where: t.id in ^Enum.map(tokens_to_expire, & &1.id)))
{:ok, {user, tokens_to_expire}}
end
end
end