ash/documentation/dsls/DSL:-Ash.Reactor.md

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# DSL: Ash.Reactor

`Ash.Reactor` is a [`Reactor`](https://hex.pm/packages/reactor) extension
which provides steps for working with Ash resources and actions.

See the [Ash Reactor Guide](https://hexdocs.pm/ash/reactor.html) for more
information.


## ash
Ash-related configuration for the `Ash.Reactor` extension






### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`default_domain`](#ash-default_domain){: #ash-default_domain } | `module` |  | A domain to use by default when calling actions |





## reactor.action
```elixir
action name, resource, action \\ nil
```


Declares a step that will call a generic action on a resource.

> #### Undo behaviour {: .tip}
>
> This step has three different modes of undo.
>
> * `never` - The result of the action is never undone.  This is the default.
> * `always` - The `undo_action` will always be called.
> * `outside_transaction` - The `undo_action` will not be called when running inside a `transaction` block, but will be otherwise.



### Nested DSLs
 * [actor](#reactor-action-actor)
 * [inputs](#reactor-action-inputs)
 * [tenant](#reactor-action-tenant)
 * [wait_for](#reactor-action-wait_for)




### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`name`](#reactor-action-name){: #reactor-action-name .spark-required} | `atom` |  | A unique name for the step. |
| [`resource`](#reactor-action-resource){: #reactor-action-resource .spark-required} | `module` |  | The resource to call the action on. |
| [`action`](#reactor-action-action){: #reactor-action-action } | `atom` |  | The name of the action to call on the resource. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`domain`](#reactor-action-domain){: #reactor-action-domain } | `module` |  | The Domain to use when calling the action.  Defaults to the Domain set on the resource or in the `ash` section. |
| [`async?`](#reactor-action-async?){: #reactor-action-async? } | `boolean` | `true` | When set to true the step will be executed asynchronously via Reactor's `TaskSupervisor`. |
| [`authorize?`](#reactor-action-authorize?){: #reactor-action-authorize? } | `boolean \| nil` |  | Explicitly enable or disable authorization for the action. |
| [`description`](#reactor-action-description){: #reactor-action-description } | `String.t` |  | A description for the step |
| [`undo_action`](#reactor-action-undo_action){: #reactor-action-undo_action } | `atom` |  | The name of the action to call on the resource when the step is to be undone. |
| [`undo`](#reactor-action-undo){: #reactor-action-undo } | `:always \| :never \| :outside_transaction` | `:never` | How to handle undoing this action |


## reactor.action.actor
```elixir
actor source
```


Specifies the action actor





### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`source`](#reactor-action-actor-source){: #reactor-action-actor-source .spark-required} | `Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value` |  | What to use as the source of the actor. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-action-actor-transform){: #reactor-action-actor-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which can be used to modify the actor before it is passed to the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Actor`

## reactor.action.inputs
```elixir
inputs template
```


Specify the inputs for an action



### Examples
```
inputs %{
  author: result(:get_user),
  title: input(:title),
  body: input(:body)
}

```

```
inputs(author: result(:get_user))

```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`template`](#reactor-action-inputs-template){: #reactor-action-inputs-template .spark-required} | `%{optional(atom) => Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value} \| keyword(Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value)` |  |  |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-action-inputs-transform){: #reactor-action-inputs-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which will transform the inputs before executing the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Inputs`

## reactor.action.tenant
```elixir
tenant source
```


Specifies the action tenant





### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`source`](#reactor-action-tenant-source){: #reactor-action-tenant-source .spark-required} | `Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value` |  | What to use as the source of the tenant. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-action-tenant-transform){: #reactor-action-tenant-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which can be used to modify the tenant before it is passed to the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Tenant`

## reactor.action.wait_for
```elixir
wait_for names
```


Wait for the named step to complete before allowing this one to start.

Desugars to `argument :_, result(step_to_wait_for)`




### Examples
```
wait_for :create_user
```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`names`](#reactor-action-wait_for-names){: #reactor-action-wait_for-names .spark-required} | `atom \| list(atom)` |  | The name of the step to wait for. |






### Introspection

Target: `Reactor.Dsl.WaitFor`




### Introspection

Target: `Ash.Reactor.Dsl.Action`



## reactor.change
```elixir
change name, change
```


Declares a step that will modify a changeset.

### Nested DSLs
 * [argument](#reactor-change-argument)
 * [wait_for](#reactor-change-wait_for)




### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`name`](#reactor-change-name){: #reactor-change-name .spark-required} | `atom` |  | A unique name for this step. |
| [`change`](#reactor-change-change){: #reactor-change-change .spark-required} | `(any, any -> any) \| module` |  | The module and options for a change. Also accepts a function that takes the changeset and the context. See `Ash.Resource.Change.Builtins` for builtin changes. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`initial`](#reactor-change-initial){: #reactor-change-initial .spark-required} | `module \| Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value` |  | The initial value to work from, either a resource or a changeset |
| [`description`](#reactor-change-description){: #reactor-change-description } | `String.t \| nil` |  | An optional description for the change |
| [`only_when_valid?`](#reactor-change-only_when_valid?){: #reactor-change-only_when_valid? } | `boolean` | `false` | If the change should only be run on valid changes. By default, all changes are run unless stated otherwise here. |
| [`where`](#reactor-change-where){: #reactor-change-where } | `(any -> any) \| module \| list((any -> any) \| module)` | `[]` | Validations that should pass in order for this change to apply. These validations failing will result in this change being ignored. |
| [`fail_if_invalid?`](#reactor-change-fail_if_invalid?){: #reactor-change-fail_if_invalid? } | `boolean` | `false` | Fail if the result of the change is an invalid changeset |


## reactor.change.argument
```elixir
argument name, source \\ nil
```


Specifies an argument to a Reactor step.

Each argument is a value which is either the result of another step, or an input value.

Individual arguments can be transformed with an arbitrary function before
being passed to any steps.




### Examples
```
argument :name, input(:name)

```

```
argument :year, input(:date, [:year])

```

```
argument :user, result(:create_user)

```

```
argument :user_id, result(:create_user) do
  transform & &1.id
end

```

```
argument :user_id, result(:create_user, [:id])

```

```
argument :three, value(3)

```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`name`](#reactor-change-argument-name){: #reactor-change-argument-name .spark-required} | `atom` |  | The name of the argument which will be used as the key in the `arguments` map passed to the implementation. |
| [`source`](#reactor-change-argument-source){: #reactor-change-argument-source .spark-required} | `Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value` |  | What to use as the source of the argument. See `Reactor.Dsl.Argument` for more information. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-change-argument-transform){: #reactor-change-argument-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which can be used to modify the argument before it is passed to the step. |





### Introspection

Target: `Reactor.Dsl.Argument`

## reactor.change.wait_for
```elixir
wait_for names
```


Wait for the named step to complete before allowing this one to start.

Desugars to `argument :_, result(step_to_wait_for)`




### Examples
```
wait_for :create_user
```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`names`](#reactor-change-wait_for-names){: #reactor-change-wait_for-names .spark-required} | `atom \| list(atom)` |  | The name of the step to wait for. |






### Introspection

Target: `Reactor.Dsl.WaitFor`




### Introspection

Target: `Ash.Reactor.Dsl.Change`



## reactor.create
```elixir
create name, resource, action \\ nil
```


Declares a step that will call a create action on a resource.

> #### Undo behaviour {: .tip}
>
> This step has three different modes of undo.
>
> * `never` - The result of the action is never undone.  This is the default.
> * `always` - The `undo_action` will always be called.
> * `outside_transaction` - The `undo_action` will not be called when running inside a `transaction` block, but will be otherwise.



### Nested DSLs
 * [actor](#reactor-create-actor)
 * [inputs](#reactor-create-inputs)
 * [tenant](#reactor-create-tenant)
 * [wait_for](#reactor-create-wait_for)


### Examples
```
create :create_post, MyApp.Post, :create do
  inputs %{
    title: input(:post_title),
    author_id: result(:get_user, [:id])
  }
  actor result(:get_user)
  tenant result(:get_organisation, [:id])
end

```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`name`](#reactor-create-name){: #reactor-create-name .spark-required} | `atom` |  | A unique name for the step. |
| [`resource`](#reactor-create-resource){: #reactor-create-resource .spark-required} | `module` |  | The resource to call the action on. |
| [`action`](#reactor-create-action){: #reactor-create-action } | `atom` |  | The name of the action to call on the resource. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`initial`](#reactor-create-initial){: #reactor-create-initial } | `nil \| module \| Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value` |  | The initial value passed into the action. |
| [`upsert_identity`](#reactor-create-upsert_identity){: #reactor-create-upsert_identity } | `atom` |  | The identity to use for the upsert |
| [`upsert?`](#reactor-create-upsert?){: #reactor-create-upsert? } | `boolean` | `false` | Whether or not this action should be executed as an upsert. |
| [`domain`](#reactor-create-domain){: #reactor-create-domain } | `module` |  | The Domain to use when calling the action.  Defaults to the Domain set on the resource or in the `ash` section. |
| [`async?`](#reactor-create-async?){: #reactor-create-async? } | `boolean` | `true` | When set to true the step will be executed asynchronously via Reactor's `TaskSupervisor`. |
| [`authorize?`](#reactor-create-authorize?){: #reactor-create-authorize? } | `boolean \| nil` |  | Explicitly enable or disable authorization for the action. |
| [`description`](#reactor-create-description){: #reactor-create-description } | `String.t` |  | A description for the step |
| [`undo_action`](#reactor-create-undo_action){: #reactor-create-undo_action } | `atom` |  | The name of the action to call on the resource when the step is to be undone. |
| [`undo`](#reactor-create-undo){: #reactor-create-undo } | `:always \| :never \| :outside_transaction` | `:never` | How to handle undoing this action |


## reactor.create.actor
```elixir
actor source
```


Specifies the action actor





### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`source`](#reactor-create-actor-source){: #reactor-create-actor-source .spark-required} | `Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value` |  | What to use as the source of the actor. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-create-actor-transform){: #reactor-create-actor-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which can be used to modify the actor before it is passed to the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Actor`

## reactor.create.inputs
```elixir
inputs template
```


Specify the inputs for an action



### Examples
```
inputs %{
  author: result(:get_user),
  title: input(:title),
  body: input(:body)
}

```

```
inputs(author: result(:get_user))

```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`template`](#reactor-create-inputs-template){: #reactor-create-inputs-template .spark-required} | `%{optional(atom) => Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value} \| keyword(Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value)` |  |  |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-create-inputs-transform){: #reactor-create-inputs-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which will transform the inputs before executing the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Inputs`

## reactor.create.tenant
```elixir
tenant source
```


Specifies the action tenant





### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`source`](#reactor-create-tenant-source){: #reactor-create-tenant-source .spark-required} | `Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value` |  | What to use as the source of the tenant. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-create-tenant-transform){: #reactor-create-tenant-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which can be used to modify the tenant before it is passed to the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Tenant`

## reactor.create.wait_for
```elixir
wait_for names
```


Wait for the named step to complete before allowing this one to start.

Desugars to `argument :_, result(step_to_wait_for)`




### Examples
```
wait_for :create_user
```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`names`](#reactor-create-wait_for-names){: #reactor-create-wait_for-names .spark-required} | `atom \| list(atom)` |  | The name of the step to wait for. |






### Introspection

Target: `Reactor.Dsl.WaitFor`




### Introspection

Target: `Ash.Reactor.Dsl.Create`



## reactor.destroy
```elixir
destroy name, resource, action \\ nil
```


Declares a step that will call a destroy action on a resource.

> #### Undo behaviour {: .tip}
>
> This step has three different modes of undo.
>
> * `never` - The result of the action is never undone.  This is the default.
> * `always` - The `undo_action` will always be called.
> * `outside_transaction` - The `undo_action` will not be called when running inside a `transaction` block, but will be otherwise.



### Nested DSLs
 * [actor](#reactor-destroy-actor)
 * [inputs](#reactor-destroy-inputs)
 * [tenant](#reactor-destroy-tenant)
 * [wait_for](#reactor-destroy-wait_for)


### Examples
```
destroy :delete_post, MyApp.Post, :destroy do
  initial input(:post)
  actor result(:get_user)
  tenant result(:get_organisation, [:id])
end

```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`name`](#reactor-destroy-name){: #reactor-destroy-name .spark-required} | `atom` |  | A unique name for the step. |
| [`resource`](#reactor-destroy-resource){: #reactor-destroy-resource .spark-required} | `module` |  | The resource to call the action on. |
| [`action`](#reactor-destroy-action){: #reactor-destroy-action } | `atom` |  | The name of the action to call on the resource. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`initial`](#reactor-destroy-initial){: #reactor-destroy-initial .spark-required} | `Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value` |  | The record to update. |
| [`return_destroyed?`](#reactor-destroy-return_destroyed?){: #reactor-destroy-return_destroyed? } | `boolean` | `false` | Whether or not the step should return the destroyed record upon completion. |
| [`domain`](#reactor-destroy-domain){: #reactor-destroy-domain } | `module` |  | The Domain to use when calling the action.  Defaults to the Domain set on the resource or in the `ash` section. |
| [`async?`](#reactor-destroy-async?){: #reactor-destroy-async? } | `boolean` | `true` | When set to true the step will be executed asynchronously via Reactor's `TaskSupervisor`. |
| [`authorize?`](#reactor-destroy-authorize?){: #reactor-destroy-authorize? } | `boolean \| nil` |  | Explicitly enable or disable authorization for the action. |
| [`description`](#reactor-destroy-description){: #reactor-destroy-description } | `String.t` |  | A description for the step |
| [`undo_action`](#reactor-destroy-undo_action){: #reactor-destroy-undo_action } | `atom` |  | The name of the action to call on the resource when the step is to be undone. |
| [`undo`](#reactor-destroy-undo){: #reactor-destroy-undo } | `:always \| :never \| :outside_transaction` | `:never` | How to handle undoing this action |


## reactor.destroy.actor
```elixir
actor source
```


Specifies the action actor





### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`source`](#reactor-destroy-actor-source){: #reactor-destroy-actor-source .spark-required} | `Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value` |  | What to use as the source of the actor. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-destroy-actor-transform){: #reactor-destroy-actor-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which can be used to modify the actor before it is passed to the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Actor`

## reactor.destroy.inputs
```elixir
inputs template
```


Specify the inputs for an action



### Examples
```
inputs %{
  author: result(:get_user),
  title: input(:title),
  body: input(:body)
}

```

```
inputs(author: result(:get_user))

```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`template`](#reactor-destroy-inputs-template){: #reactor-destroy-inputs-template .spark-required} | `%{optional(atom) => Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value} \| keyword(Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value)` |  |  |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-destroy-inputs-transform){: #reactor-destroy-inputs-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which will transform the inputs before executing the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Inputs`

## reactor.destroy.tenant
```elixir
tenant source
```


Specifies the action tenant





### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`source`](#reactor-destroy-tenant-source){: #reactor-destroy-tenant-source .spark-required} | `Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value` |  | What to use as the source of the tenant. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-destroy-tenant-transform){: #reactor-destroy-tenant-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which can be used to modify the tenant before it is passed to the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Tenant`

## reactor.destroy.wait_for
```elixir
wait_for names
```


Wait for the named step to complete before allowing this one to start.

Desugars to `argument :_, result(step_to_wait_for)`




### Examples
```
wait_for :create_user
```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`names`](#reactor-destroy-wait_for-names){: #reactor-destroy-wait_for-names .spark-required} | `atom \| list(atom)` |  | The name of the step to wait for. |






### Introspection

Target: `Reactor.Dsl.WaitFor`




### Introspection

Target: `Ash.Reactor.Dsl.Destroy`



## reactor.read_one
```elixir
read_one name, resource, action \\ nil
```


Declares a step that will call a read action on a resource returning a single record.

### Nested DSLs
 * [actor](#reactor-read_one-actor)
 * [inputs](#reactor-read_one-inputs)
 * [tenant](#reactor-read_one-tenant)
 * [wait_for](#reactor-read_one-wait_for)


### Examples
```
read_one :post_by_id, MyApp.Post, :read do
  inputs %{id: input(:post_id)}
end

```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`name`](#reactor-read_one-name){: #reactor-read_one-name .spark-required} | `atom` |  | A unique name for the step. |
| [`resource`](#reactor-read_one-resource){: #reactor-read_one-resource .spark-required} | `module` |  | The resource to call the action on. |
| [`action`](#reactor-read_one-action){: #reactor-read_one-action } | `atom` |  | The name of the action to call on the resource. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`fail_on_not_found?`](#reactor-read_one-fail_on_not_found?){: #reactor-read_one-fail_on_not_found? } | `boolean` | `false` | When set to true the step will fail if the resource is not found. |
| [`domain`](#reactor-read_one-domain){: #reactor-read_one-domain } | `module` |  | The Domain to use when calling the action.  Defaults to the Domain set on the resource or in the `ash` section. |
| [`async?`](#reactor-read_one-async?){: #reactor-read_one-async? } | `boolean` | `true` | When set to true the step will be executed asynchronously via Reactor's `TaskSupervisor`. |
| [`authorize?`](#reactor-read_one-authorize?){: #reactor-read_one-authorize? } | `boolean \| nil` |  | Explicitly enable or disable authorization for the action. |
| [`description`](#reactor-read_one-description){: #reactor-read_one-description } | `String.t` |  | A description for the step |


## reactor.read_one.actor
```elixir
actor source
```


Specifies the action actor





### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`source`](#reactor-read_one-actor-source){: #reactor-read_one-actor-source .spark-required} | `Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value` |  | What to use as the source of the actor. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-read_one-actor-transform){: #reactor-read_one-actor-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which can be used to modify the actor before it is passed to the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Actor`

## reactor.read_one.inputs
```elixir
inputs template
```


Specify the inputs for an action



### Examples
```
inputs %{
  author: result(:get_user),
  title: input(:title),
  body: input(:body)
}

```

```
inputs(author: result(:get_user))

```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`template`](#reactor-read_one-inputs-template){: #reactor-read_one-inputs-template .spark-required} | `%{optional(atom) => Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value} \| keyword(Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value)` |  |  |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-read_one-inputs-transform){: #reactor-read_one-inputs-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which will transform the inputs before executing the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Inputs`

## reactor.read_one.tenant
```elixir
tenant source
```


Specifies the action tenant





### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`source`](#reactor-read_one-tenant-source){: #reactor-read_one-tenant-source .spark-required} | `Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value` |  | What to use as the source of the tenant. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-read_one-tenant-transform){: #reactor-read_one-tenant-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which can be used to modify the tenant before it is passed to the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Tenant`

## reactor.read_one.wait_for
```elixir
wait_for names
```


Wait for the named step to complete before allowing this one to start.

Desugars to `argument :_, result(step_to_wait_for)`




### Examples
```
wait_for :create_user
```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`names`](#reactor-read_one-wait_for-names){: #reactor-read_one-wait_for-names .spark-required} | `atom \| list(atom)` |  | The name of the step to wait for. |






### Introspection

Target: `Reactor.Dsl.WaitFor`




### Introspection

Target: `Ash.Reactor.Dsl.ReadOne`



## reactor.read
```elixir
read name, resource, action \\ nil
```


Declares a step that will call a read action on a resource.

### Nested DSLs
 * [actor](#reactor-read-actor)
 * [inputs](#reactor-read-inputs)
 * [tenant](#reactor-read-tenant)
 * [wait_for](#reactor-read-wait_for)


### Examples
```
read :read_posts, MyApp.Post, :read

```

```
read :read_posts_in_range, MyApp.Post, :read_in_range do
  inputs %{min_date: input(:min_date), max_date: input(:max_date)}
end

```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`name`](#reactor-read-name){: #reactor-read-name .spark-required} | `atom` |  | A unique name for the step. |
| [`resource`](#reactor-read-resource){: #reactor-read-resource .spark-required} | `module` |  | The resource to call the action on. |
| [`action`](#reactor-read-action){: #reactor-read-action } | `atom` |  | The name of the action to call on the resource. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`domain`](#reactor-read-domain){: #reactor-read-domain } | `module` |  | The Domain to use when calling the action.  Defaults to the Domain set on the resource or in the `ash` section. |
| [`async?`](#reactor-read-async?){: #reactor-read-async? } | `boolean` | `true` | When set to true the step will be executed asynchronously via Reactor's `TaskSupervisor`. |
| [`authorize?`](#reactor-read-authorize?){: #reactor-read-authorize? } | `boolean \| nil` |  | Explicitly enable or disable authorization for the action. |
| [`description`](#reactor-read-description){: #reactor-read-description } | `String.t` |  | A description for the step |


## reactor.read.actor
```elixir
actor source
```


Specifies the action actor





### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`source`](#reactor-read-actor-source){: #reactor-read-actor-source .spark-required} | `Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value` |  | What to use as the source of the actor. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-read-actor-transform){: #reactor-read-actor-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which can be used to modify the actor before it is passed to the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Actor`

## reactor.read.inputs
```elixir
inputs template
```


Specify the inputs for an action



### Examples
```
inputs %{
  author: result(:get_user),
  title: input(:title),
  body: input(:body)
}

```

```
inputs(author: result(:get_user))

```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`template`](#reactor-read-inputs-template){: #reactor-read-inputs-template .spark-required} | `%{optional(atom) => Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value} \| keyword(Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value)` |  |  |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-read-inputs-transform){: #reactor-read-inputs-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which will transform the inputs before executing the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Inputs`

## reactor.read.tenant
```elixir
tenant source
```


Specifies the action tenant





### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`source`](#reactor-read-tenant-source){: #reactor-read-tenant-source .spark-required} | `Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value` |  | What to use as the source of the tenant. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-read-tenant-transform){: #reactor-read-tenant-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which can be used to modify the tenant before it is passed to the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Tenant`

## reactor.read.wait_for
```elixir
wait_for names
```


Wait for the named step to complete before allowing this one to start.

Desugars to `argument :_, result(step_to_wait_for)`




### Examples
```
wait_for :create_user
```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`names`](#reactor-read-wait_for-names){: #reactor-read-wait_for-names .spark-required} | `atom \| list(atom)` |  | The name of the step to wait for. |






### Introspection

Target: `Reactor.Dsl.WaitFor`




### Introspection

Target: `Ash.Reactor.Dsl.Read`



## reactor.transaction
```elixir
transaction name, resources
```


Creates a group of steps which will be executed inside a data layer transaction.

### Nested DSLs
 * [wait_for](#reactor-transaction-wait_for)




### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`name`](#reactor-transaction-name){: #reactor-transaction-name .spark-required} | `atom` |  | A unique name for the step. |
| [`resources`](#reactor-transaction-resources){: #reactor-transaction-resources .spark-required} | `module \| list(module)` |  | A resource or list of resources to consider in the transaction. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`return`](#reactor-transaction-return){: #reactor-transaction-return } | `atom` |  | The name of the step whose result will be returned as the return value of the transaction. |
| [`timeout`](#reactor-transaction-timeout){: #reactor-transaction-timeout } | `pos_integer \| :infinity` | `15000` | How long to allow the transaction to run before timing out. |


## reactor.transaction.wait_for
```elixir
wait_for names
```


Wait for the named step to complete before allowing this one to start.

Desugars to `argument :_, result(step_to_wait_for)`




### Examples
```
wait_for :create_user
```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`names`](#reactor-transaction-wait_for-names){: #reactor-transaction-wait_for-names .spark-required} | `atom \| list(atom)` |  | The name of the step to wait for. |






### Introspection

Target: `Reactor.Dsl.WaitFor`




### Introspection

Target: `Ash.Reactor.Dsl.Transaction`



## reactor.update
```elixir
update name, resource, action \\ nil
```


Declares a step that will call an update action on a resource.

> #### Undo behaviour {: .tip}
>
> This step has three different modes of undo.
>
> * `never` - The result of the action is never undone.  This is the default.
> * `always` - The `undo_action` will always be called.
> * `outside_transaction` - The `undo_action` will not be called when running inside a `transaction` block, but will be otherwise.



### Nested DSLs
 * [actor](#reactor-update-actor)
 * [inputs](#reactor-update-inputs)
 * [tenant](#reactor-update-tenant)
 * [wait_for](#reactor-update-wait_for)


### Examples
```
update :publish_post, MyApp.Post, :update do
  initial input(:post)
  inputs %{
    published: value(true)
  }
  actor result(:get_user)
  tenant result(:get_organisation, [:id])
end

```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`name`](#reactor-update-name){: #reactor-update-name .spark-required} | `atom` |  | A unique name for the step. |
| [`resource`](#reactor-update-resource){: #reactor-update-resource .spark-required} | `module` |  | The resource to call the action on. |
| [`action`](#reactor-update-action){: #reactor-update-action } | `atom` |  | The name of the action to call on the resource. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`initial`](#reactor-update-initial){: #reactor-update-initial .spark-required} | `Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value` |  | The record to update. |
| [`domain`](#reactor-update-domain){: #reactor-update-domain } | `module` |  | The Domain to use when calling the action.  Defaults to the Domain set on the resource or in the `ash` section. |
| [`async?`](#reactor-update-async?){: #reactor-update-async? } | `boolean` | `true` | When set to true the step will be executed asynchronously via Reactor's `TaskSupervisor`. |
| [`authorize?`](#reactor-update-authorize?){: #reactor-update-authorize? } | `boolean \| nil` |  | Explicitly enable or disable authorization for the action. |
| [`description`](#reactor-update-description){: #reactor-update-description } | `String.t` |  | A description for the step |
| [`undo_action`](#reactor-update-undo_action){: #reactor-update-undo_action } | `atom` |  | The name of the action to call on the resource when the step is to be undone. |
| [`undo`](#reactor-update-undo){: #reactor-update-undo } | `:always \| :never \| :outside_transaction` | `:never` | How to handle undoing this action |


## reactor.update.actor
```elixir
actor source
```


Specifies the action actor





### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`source`](#reactor-update-actor-source){: #reactor-update-actor-source .spark-required} | `Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value` |  | What to use as the source of the actor. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-update-actor-transform){: #reactor-update-actor-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which can be used to modify the actor before it is passed to the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Actor`

## reactor.update.inputs
```elixir
inputs template
```


Specify the inputs for an action



### Examples
```
inputs %{
  author: result(:get_user),
  title: input(:title),
  body: input(:body)
}

```

```
inputs(author: result(:get_user))

```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`template`](#reactor-update-inputs-template){: #reactor-update-inputs-template .spark-required} | `%{optional(atom) => Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value} \| keyword(Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value)` |  |  |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-update-inputs-transform){: #reactor-update-inputs-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which will transform the inputs before executing the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Inputs`

## reactor.update.tenant
```elixir
tenant source
```


Specifies the action tenant





### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`source`](#reactor-update-tenant-source){: #reactor-update-tenant-source .spark-required} | `Reactor.Template.Input \| Reactor.Template.Result \| Reactor.Template.Value` |  | What to use as the source of the tenant. |
### Options

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`transform`](#reactor-update-tenant-transform){: #reactor-update-tenant-transform } | `(any -> any) \| module \| nil` |  | An optional transformation function which can be used to modify the tenant before it is passed to the action. |





### Introspection

Target: `Ash.Reactor.Dsl.Tenant`

## reactor.update.wait_for
```elixir
wait_for names
```


Wait for the named step to complete before allowing this one to start.

Desugars to `argument :_, result(step_to_wait_for)`




### Examples
```
wait_for :create_user
```



### Arguments

| Name | Type | Default | Docs |
|------|------|---------|------|
| [`names`](#reactor-update-wait_for-names){: #reactor-update-wait_for-names .spark-required} | `atom \| list(atom)` |  | The name of the step to wait for. |






### Introspection

Target: `Reactor.Dsl.WaitFor`




### Introspection

Target: `Ash.Reactor.Dsl.Update`



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