View Source Ash.Policy.Check behaviour (ash v3.4.45)

A behaviour for declaring checks, which can be used to easily construct authorization rules.

If a check can be expressed simply, i.e as a function of the actor, or the context of the request, see Ash.Policy.SimpleCheck for an easy way to write that check. If a check can be expressed with a filter statement, see Ash.Policy.FilterCheck for an easy way to write that check.

Summary

Types

actor()
authorizer()
check_type()
options()
ref()
t()

Callbacks

auto_filter(actor, authorizer, options)

An optional callback, that allows the check to work with policies set to access_type :filter

check(actor, list, map, options)

An optional callback, hat allows the check to work with policies set to access_type :runtime

describe(options)

Describe the check in human readable format, given the options

eager_evaluate?()
expand_description(actor, authorizer, options)

Expands the description of the check, given the actor and subject

prefer_expanded_description?()

Whether or not the expanded description should replace the basic description in breakdowns

requires_original_data?(actor, options)

Whether or not your check requires the original data of a changeset (if applicable)

strict_check(actor, authorizer, options)

Strict checks should be cheap, and should never result in external calls (like database or domain)

type()

The type of the check

Functions

defines_auto_filter?(module)
defines_check?(module)

Types

actor()

@type actor() :: any()

authorizer()

@type authorizer() :: Ash.Policy.Authorizer.t()

check_type()

@type check_type() :: :simple | :filter | :manual

options()

@type options() :: Keyword.t()

ref()

@type ref() :: {module(), Keyword.t()} | module()

t()

@type t() :: %Ash.Policy.Check{
  check: term(),
  check_module: term(),
  check_opts: term(),
  type: term()
}

Callbacks

auto_filter(actor, authorizer, options)

(optional) 
@callback auto_filter(actor(), authorizer(), options()) :: Keyword.t() | Ash.Expr.t()

An optional callback, that allows the check to work with policies set to access_type :filter

Return a keyword list filter that will be applied to the query being made, and will scope the results to match the rule

check(actor, list, map, options)

(optional) 
@callback check(actor(), [Ash.Resource.record()], map(), options()) :: [
  Ash.Resource.record()
]

An optional callback, hat allows the check to work with policies set to access_type :runtime

Takes a list of records, and returns the subset of authorized records.

describe(options)

@callback describe(options()) :: String.t()

Describe the check in human readable format, given the options

eager_evaluate?()

@callback eager_evaluate?() :: boolean()

expand_description(actor, authorizer, options)

(optional) 
@callback expand_description(
  actor(),
  authorizer(),
  options()
) :: {:ok, String.t()} | :none

Expands the description of the check, given the actor and subject

prefer_expanded_description?()

@callback prefer_expanded_description?() :: boolean()

Whether or not the expanded description should replace the basic description in breakdowns

requires_original_data?(actor, options)

@callback requires_original_data?(actor(), options()) :: boolean()

Whether or not your check requires the original data of a changeset (if applicable)

strict_check(actor, authorizer, options)

@callback strict_check(actor(), authorizer(), options()) ::
  {:ok, boolean() | :unknown} | {:error, term()}

Strict checks should be cheap, and should never result in external calls (like database or domain)

It should return {:ok, true} if it can tell that the request is authorized, and {:ok, false} if it can tell that it is not. If unsure, it should return {:ok, :unknown}

type()

@callback type() :: check_type()

The type of the check

:manual checks must be written by hand as standard check modules :filter checks can use Ash.Policy.FilterCheck for simplicity :simple checks can use Ash.Policy.SimpleCheck for simplicity

Functions

defines_auto_filter?(module)

defines_check?(module)