GraphQL: the good, the bad, the f* cool

Transcript

1. GRAPHQL THE GOOD, THE BAD, THE F* COOL 1
2. ABOUT ME I didn't write a controller for almost 2 years 2
3. WHAT GRAPHQL IS? A speci cation for a Graph based API Queries - No side effect Mutations - Side effet Subscriptions - Pub/Sub or Noti cations 3
4. WHAT GRAPHQL HELP US TO ACHIEVE AS A TEAM Fast iterations Multi disciplinary teams Documentation for free Centralized logic Descentralized information Made life boring 4
5. WARNINGS Limited experience Speci c scenario Biased by tooling 5
6. WHAT PROBLEM GRAPHQL SOLVES? 6
7. GET https://api.github.com/organizations/github { "login": "github", "id": 1, "node_id": "MDEyOk9yZ2FuaXphdGlvbjE=", "url": "https://api.github.com/orgs/github", "repos_url": "https://api.github.com/orgs/github/repos", "events_url": "https://api.github.com/orgs/github/events", "hooks_url": "https://api.github.com/orgs/github/hooks", "issues_url": "https://api.github.com/orgs/github/issues", "description": "A great organization", "name": "github", "company": "GitHub", "location": "San Francisco", "email": "octocat@github.com", "is_verified": true, ... } 7
8. GET https://api.github.com/orgs/github/repos [ { "id": 1296269, "name": "Hello-World", "full_name": "octocat/Hello-World", "private": false, "description": "This your first repo!", "fork": false, "branches_url": "http://api.gthub.com/repos/octocat/Hello-World/branches{/branch} "commits_url": "http://api.github.com/repos/octocat/Hello-World/commits{/sha}", "language": null, "forks_count": 9, "stargazers_count": 80, "pushed_at": "2011-01-26T19:06:43Z", "created_at": "2011-01-26T19:01:12Z", ... } ] 8
10. EFFICIENCY Underfetch: make a request again, and again... Overfetch: too much data 1 MB from SSD: 400us 1 MB from America to Europe: 150ms 10
12. QUERY { viewer { login bio company } } { "data": { "viewer": { "login": "pmargreff", "bio": "I'm the dog, not the human. ", "company": null } } } 12
13. QUERY WITH ARGUMENT user(login: "josevalim") { { 1 2 name 3 bio 4 company 5 } 6 } 7 { "data": { "user": { "name": "José Valim", "bio": "Creator of @elixir-lang.", "company": "@dashbitco " } } } 13 . 1
14. GRAPHQL VS REST { viewer { login bio company } } curl https://github.com/api/v3/users/josevalim 13 . 2
15. REST USER RESPONSE { "login": "octocat", "id": 1, "node_id": "MDQ6VXNlcjE=", "avatar_url": "https://github.com/images/error/octocat_happy.gif", "gravatar_id": "", "url": "https://api.github.com/users/octocat", "html_url": "https://github.com/octocat", "followers_url": "https://api.github.com/users/octocat/followers", "following_url": "https://api.github.com/users/octocat/following{/other_user}", "gists_url": "https://api.github.com/users/octocat/gists{/gist_id}", "starred_url": "https://api.github.com/users/octocat/starred{/owner}{/repo}", "subscriptions_url": "https://api.github.com/users/octocat/subscriptions", "organizations_url": "https://api.github.com/users/octocat/orgs", "repos_url": "https://api.github.com/users/octocat/repos", "events_url": "https://api.github.com/users/octocat/events{/privacy}", "received_events_url": "https://api.github.com/users/octocat/received_events", "type": "User", "site_admin": false, "name": "monalisa octocat", "company": "GitHub", 13 . 3
16. QUERY WITH NODES { user(login: "josevalim") { login name repositoriesContributedTo(first: 3, contributionTypes: ISSUE) { nodes { name languages(first: 2) { nodes { name } } } } } } 14
17. QUERY WITH MULTIPLE NODES { "data": { "user": { "login": "josevalim", "name": "José Valim", "repositoriesContributedTo": { "nodes": [ { "name": "elixir", "languages": { "nodes": [ { "name": "Shell" }, { "name": "PowerShell" } ] } }, 15 . 1
18. REST 1 - curl https://api.github.com/users/josevalim 2 - curl https://api.github.com/users/josevalim/events/public 3 - filter issues events 4 - filter repos from issues 5 - sort and get {5} 6 - curl https://api.github.com/repos/elixir/elixir-lang/languages 7 - curl https://api.github.com/repos/erlang/cowboy/languages . . . 15 . 2
19. { user(login: "josevalim") { name bio company } } 1 2 3 4 5 6 7 type Query { user(login: String!): User } type User { name: String! bio: String company: String ... } 1 2 3 4 5 6 7 8 9 10 16
20. user(login: "josevalim") { { 1 2 name 3 bio 4 company 5 } 6 } 7 user(login: String!): User type Query { 1 2 } 3 4 type User { 5 name: String! 6 bio: String 7 company: String 8 ... 9 } 10 17
21. name bio company { 1 user(login: "josevalim") { 2 3 4 5 } 6 } 7 type User { name: String! bio: String company: String ... } type Query { 1 user(login: String!): User 2 } 3 4 5 6 7 8 9 10 18
22. GraphiQL 19 . 1
23. Voyager 19 . 2
24. user(login: String!): User type Query { 1 2 } 3 query do @desc "Get a user by name" field :user, :user do arg(:login, non_null(:string)) resolve(&Resolvers.User.get_user_by_login/2) end end 1 2 3 4 5 6 7 @desc "Get a user by name" query do 1 2 field :user, :user do 3 arg(:login, non_null(:string)) 4 resolve(&Resolvers.User.get_user_by_login/2) 5 end 6 end 7 arg(:login, non_null(:string)) query do 1 @desc "Get a user by name" 2 field :user, :user do 3 4 resolve(&Resolvers.User.get_user_by_login/2) 5 end 6 end 7 resolve(&Resolvers.User.get_user_by_login/2) query do 1 @desc "Get a user by name" 2 field :user, :user do 3 arg(:login, non_null(:string)) 4 5 end 6 end 7 field :user, :user do query do 1 @desc "Get a user by name" 2 3 arg(:login, non_null(:string)) 4 resolve(&Resolvers.User.get_user_by_login/2) 5 end 6 end 7 20
25. name: String bio: String company: String login: String! type User { 1 2 3 4 5 repositories: [Repository! 6 } 7 repositories: [Repository! type User { 1 name: String 2 bio: String 3 company: String 4 login: String! 5 6 } 7 field :name, :string field :bio, :string field :company, :string field :login, non_null(:string) object :user do 1 2 3 4 5 6 field :repositories, list_of(:repository) do 7 resolve(&Resolvers.User.list_repos/3) 8 end 9 end 10 field :repositories, list_of(:repository) do resolve(&Resolvers.User.list_repos/3) end object :user do 1 field :name, :string 2 field :bio, :string 3 field :company, :string 4 field :login, non_null(:string) 5 6 7 8 9 end 10 21
26. GRAPHQL AS SERVICE AGGREGATOR def list_repos(%{user_id: user_id}, _args, _resolution) do Users.list_repo_by_user(user_id) end 1 2 3 4 def list_repos(%{user_id: user_id}, _args, _resolution) do 5 Repository.Client.list_by_user(user_id) 6 |> Repository.Parser.from_request_to_schema() 7 end 8 9 def list_repos(%{user_id: user_id}, _args, _resolution) do 10 GRPCServer.Repository.get_user(user_id) 11 end 12 def list_repos(%{user_id: user_id}, _args, _resolution) do Repository.Client.list_by_user(user_id) |> Repository.Parser.from_request_to_schema() end def list_repos(%{user_id: user_id}, _args, _resolution) do 1 Users.list_repo_by_user(user_id) 2 end 3 4 5 6 7 8 9 def list_repos(%{user_id: user_id}, _args, _resolution) do 10 GRPCServer.Repository.get_user(user_id) 11 end 12 def list_repos(%{user_id: user_id}, _args, _resolution) do GRPCServer.Repository.get_user(user_id) end def list_repos(%{user_id: user_id}, _args, _resolution) do 1 Users.list_repo_by_user(user_id) 2 end 3 4 def list_repos(%{user_id: user_id}, _args, _resolution) do 5 Repository.Client.list_by_user(user_id) 6 |> Repository.Parser.from_request_to_schema() 7 end 8 9 10 11 12 22
27. GRAPHQL AS SERVICE AGGREGATOR Umbrella applications (monorepo) Micro-services Lambdas Geodata, Search Engines (elasticsearch, algolia, etc) Services (Salesforce, Zendesk, etc) 23
29. UNSOLVED PROBLEMS Isn't easy to gure out rate limit Test granularity Easy to reuse heavy queries Hard to remove elds Schema modeling 25
30. THAT'S ALL Enums Unions Interfaces Fragments Mutations Subscriptions Error handling 26
31. THANK YOU! 27
32. ADDITIONAL CONTENT The Do’s and Don’ts for your schema and GraphQL operations - Apollo GraphQL design tutorial - Shopify 28