# AshJsonApi
[](https://opensource.org/licenses/MIT)
[](https://hex.pm/packages/ash_json_api)
AshJsonApi allows you to take resources created with [Ash](https://github.com/ash-project/ash) and build complete JSON:API compliant endpoints with just a few lines of code.
This is what AshJsonApi does:
1. Route Creation: AshJsonApi defines routes and actions in your app based on resource configurations
2. Deserialization: When an incoming HTTP request hits a AshJsonApi defined route/action, AshJsonApi will parse it from `/api/users?filter[admin]=true` into a call to ash
3. Query Execution: AshJsonApi then executes the parsed Ash Action (this is the integration point between AshJsonApi and Ash Core, where Ash Actions are defined)
4. Serialization: AshJsonApi then serializes the result of the Ash Action into JSON API objects.
5. Response: AshJsonApi then sends this JSON back to the client
6. Schema Generation: AshJsonApi generates a machine-readable JSON Schema of your entire API and a route/action that can serve it
As you can see, Ash takes care of all of the data related work for a request (CRUD, Sorting, Filtering, Pagination, Side Loading, and Authorization) while AshJsonApi more or less replaces controllers and serializers.
The beauty of putting all of that data functionality into a non-web layer (Ash) is that it can be used in many contexts. A JSON:API is one context - but there are others such as GraphQL or just using an Ash Resource from other code within an Application. The decoupling of the web from data layers is why AshJsonApi is it's own hex package, as opposed to just a module within [Ash](https://github.com/ash-project/ash).
## Usage
Assume you have already built a resource using [Ash](https://github.com/ash-project/ash) such as this Post resource:
```elixir
defmodule Post do
use Ash.Resource,
data_layer: Ash.DataLayer.Postgres
# If no actions are defined, simple defaults are implemented called `:read`, `:create`, `:update`, `:destroy`
attributes do
attribute :name, :string
end
actions do
defaults [:create, :read, :update, :destroy]
end
relationships do
belongs_to :author, Author
end
end
```
As you can see, the resource takes care of interacting with the database, setting up attributes and relationships, as well as specifying actions (CRUD) that can be performed on the resource. What is now needed is to add a configuration for how this resource will interact with JSON:API
```elixir
defmodule Post do
use Ash.Resource,
data_layer: AshPostgres,
extensions: [AshJsonApi.Resource]
...
json_api do
# Specify a json:api resource type
type "posts"
routes do
base "/posts"
# Add a `GET /posts/:id` route, that calls into the :read action called :read
get :read
# Add a `GET /posts` route, that calls into the :read action called :read
index :read
end
end
...
```
Then, update your API with the API extension and configuration:
```elixir
defmodule MyApp.Domain do
use Ash.Domain, extensions: [AshJsonApi.Domain]
json_api do
...
end
end
```
See the hex documentation for more.
See `AshJsonApi.Domain` and `AshJsonApi.Resource` for the DSL documentation.
