No REST for the Wicked

Build a GraphQL API with http://absinthe-graphql.org/

Transcript

1. the Wicked for No REST http://absinthe-graphql.org Ben Wilson @benwilson512
2. CARGOSENSE
3. The BEAM http://absinthe-graphql.org Ben Wilson @benwilson512 some reasons to like
4. REST GET /users/1 { name: "Joe Bob" email: "joe.bob@foo.com" friends: [ "/users/5", "/users/7", "/users/9", ], organization_id: 1 } http://absinthe-graphql.org Ben Wilson @benwilson512
6. REST, Camp 2 GET /users/1 { name: "Joe Bob”, organization_id: 1, friends: [ { name: "Fred Jones", organization: { name: "Cool Folks LLC", payment_plan_id: 5 } }, … } http://absinthe-graphql.org Ben Wilson @benwilson512
8. { name: "Joe Bob” organization_id: 1, friends: [ { name: "Fred Jones", organization: { name: "Cool Folks LLC", payment_plan_id: 5 } }, … ] } GET /users/1 REST, Camp 2 http://absinthe-graphql.org Ben Wilson @benwilson512
9. GraphQL Declarative & Hierarchical Strongly Typed Concurrent Application-Focused http://absinthe-graphql.org Ben Wilson @benwilson512 some reasons to like
10. Declarative & Hierarchical http://absinthe-graphql.org Ben Wilson @benwilson512 it’s
11. GraphQL http://absinthe-graphql.org Ben Wilson @benwilson512 { user: { name: "Joe Bob", email: "joe.bob@foo.com", friends: [ {name: "Fred Jones"}, {name: "Jane Smith"}, {name: "Rebecca Jones"}, ... ] } } { user(id: 1) { name email friends { name } } }
12. http://absinthe-graphql.org Ben Wilson @benwilson512 Strongly Typed it’s
13. Directive http://absinthe-graphql.org Ben Wilson @benwilson512 List Interface Enum Union Scalar Object NonNull
14. GET /events?date=2016-08-30&location_id=4 http://absinthe-graphql.org Ben Wilson @benwilson512 @valid_filters ~w(date location_id name)a def index(conn, params) do filters = @valid_filters |> Enum.reduce(%{}, fn key, filters -> case Map.fetch(params, Atom.to_string(key)) do {:ok, value} -> add_filter(key, value, filters) _ -> query end end) render("index.json", events: Event.list(filters)) end
15. But wait! there’s more… def add_filter(:date, date, filters) do case Calendar.parse(date) do {:ok, date} -> Map.put(filters, :date, date) _ -> filters end end def add_filter(key, value, filters) do Map.put(filters, key, value) end
16. GET /events?date=2016-08-30&location_id=4 http://absinthe-graphql.org Ben Wilson @benwilson512 @valid_filters ~w(date location_id name)a def index(conn, params) do filters = @valid_filters |> Enum.reduce(%{}, fn key, filters -> case Map.fetch(params, Atom.to_string(key)) do {:ok, value} -> add_filter(key, value, filters) _ -> query end end) render("index.json", events: Event.list(filters)) end
17. { events(location_id: 4, date: "2016-08-30") { name } } http://absinthe-graphql.org Ben Wilson @benwilson512 Using: def events(filters, _) do {:ok, Event.list(filters)} end
18. { events(location_id: 4, date: "2016-08-30") { name } } http://absinthe-graphql.org Ben Wilson @benwilson512 def events(filters, _) do ... end field :events, list_of(:event) do arg :date, :date arg :location_id, :id arg :name, :string resolve &events/2 end
19. http://absinthe-graphql.org Ben Wilson @benwilson512 Custom Scalar @desc """ ISO Date 2015-11-21 2015-01-02 """ scalar :date do parse &Calendar.Date.Parse.iso8601/1 serialize &Calendar.Date.Format.iso8601/1 end
20. http://absinthe-graphql.org Ben Wilson @benwilson512 Built-in Scalar @desc """ The `String` scalar type represents textual data, represented as UTF-8 character sequences. ... """ scalar :string do serialize &to_string/1 parse &parse_string/1 end
21. http://absinthe-graphql.org Ben Wilson @benwilson512 @desc """ A planned occasion, like a meeting or conference """ object :event do @desc "The date on which the event occurs" field :date, non_null(:date) @desc "The location at which the event happens" field :location, non_null(:location) @desc "The name of the event" field :name, non_null(:string) field :attendees, list_of(:person) end
22. Introspection http://absinthe-graphql.org Ben Wilson @benwilson512 { __schema { types { name description } } } { __schema: { types: [ { name: "Event", description: "A planned …" }, { name: "Person", description: "Someone …" }, ... ] } }
23. GraphiQL http://absinthe-graphql.org Ben Wilson @benwilson512 https://github.com/graphql/graphiql
24. { user: { name: "Bob", primaryOrganization: { id: 7, name: "Elixir Co INC" } }, location: { name: "Headquarters", organization: { id: 7, name: "Elixir Co INC" } } } http://absinthe-graphql.org Ben Wilson @benwilson512
25. Directives http://absinthe-graphql.org Ben Wilson @benwilson512 { feed: { stories: [ { author: { name: "Ben Wilson" }, message: "Elixir Rocks!" }, { author: { name: "Bruce Williams" }, message: "GraphQL is the bomb!" }, ... ] } } { feed { stories { author { name } comments @defer { author { name } } message } } }
26. Deferred Content http://absinthe-graphql.org Ben Wilson @benwilson512 { path: ["feed", "stories", 0, "comments"], data: [ { author: { name: "Joe Bob", message: "Commenting is fun" } }, ... ] }
27. Directives http://absinthe-graphql.org Ben Wilson @benwilson512 { feed { stories @stream { author { name } comments @defer { author { name } } message } } } { feed { stories @live { author { name } comments @defer { author { name } } message } } } { feed { stories { author { name } comments @defer { author { name } } message } } }
28. Absinthe Goals Correct Easy to Use Idiomatic Performant Community Oriented http://absinthe-graphql.org Ben Wilson @benwilson512
29. Schema Errors web/schema.ex:12: Users :usre is not defined in your schema. Types must exist if referenced. object :organization do field :name, :string field :users, list_of(:usre) end http://absinthe-graphql.org Ben Wilson @benwilson512
30. Schema Compilation http://absinthe-graphql.org Ben Wilson @benwilson512 @desc "A faction in the Star Wars saga" node object :faction do @desc "The name of the faction" field :name, :string @desc "The ships used by the faction." connection field :ships, node_type: :ship do resolve &Ship.list/2 end end
31. Absinthe v1.2
32. ? http://absinthe-graphql.org Ben Wilson @benwilson512 { user: { name: "Joe Bob", email: "joe.bob@foo.com", friends: [ {name: "Fred Jones"}, {name: "Jane Smith"}, {name: "Rebecca Jones"}, ... ] } } { user(id: 1) { name email friends { name } } }
33. Absinthe vNext http://absinthe-graphql.org Ben Wilson @benwilson512
34. Query Compilation ~A"""
 query Fast($id: ID){ performanceCritical(id: $id) { stuff things { name } } } """ http://absinthe-graphql.org Ben Wilson @benwilson512
35. Projection http://absinthe-graphql.org Ben Wilson @benwilson512 def events(filters, _) do {:ok Event.list(filters)} end def list(filters) do Event |> where(^filters) |> Repo.all end
36. Projection http://absinthe-graphql.org Ben Wilson @benwilson512 def events(filters, graphql_info) do preloads = Absinthe.Ecto.preloads(graphql_info) selections = Absinthe.Ecto.preloads(graphql_info) {:ok Event.list(filters, preloads, selections)} end def list(filters, preloads, selections) do Event |> where(^filters) |> select(^selections) |> preload(^preloads) |> Repo.all end
37. Real Time Data http://absinthe-graphql.org Ben Wilson @benwilson512 { feed { stories @live { author { name } comments @defer { author { name } } message } } } subscription { stories(author_id: 1) { message author { name } } }
38. Questions? http://absinthe-graphql.org Ben Wilson @benwilson512 Background image green by Ana C., license available here.